Report in British Journal of Cancer provides preclinical evidence on possible health benefits of rice bran
A study by biomedical scientists at the University of Leicester has revealed for the first time that rice bran could reduce the risk of intestinal cancer.
The research in the University's Department of Cancer Studies and Molecular Medicine has not been tested on humans, but research in the laboratory has produced promising results.
The research has been published in the British Journal of Cancer.
The results of a controlled laboratory study in a preclinical model of gastrointestinal adenoma demonstrated that consumption of a high daily dose of stabilized rice bran caused an average 51% reduction in the number of precancerous adenomas in the intestinal tract.
Professor Andreas Gescher of the University of Leicester in the UK, the principal investigator, said:
"We compared the cancer-preventive efficacy of rice bran with respect to prostate, breast and intestinal cancers. Whilst there was no effect of rice bran on the development of prostate or breast cancer, rice bran significantly retarded the development of intestinal adenomas. The effect was dependent on the fibre content of the bran. The dose we used translates into approximately 200g rice bran per day in humans. We believe a promising area of future research would be to study the potential colorectal cancer-preventing properties of stabilized rice bran.
"It is known that bran from wheat and rye have anti-cancer properties but this is the first time that this has been shown for rice bran. It appears that rice bran may have a role to play in reducing the development of adenomas, which can be a pre-cursor to cancer. No one has compared the efficacy of the different brans, such as rice, wheat, rye or oat and this may be an interesting future direction for researchers."
Wednesday, March 28, 2007
Maternal beef diet could impact sperm counts
A mother’s high beef consumption while pregnant was associated with lower sperm counts in her son, according to a study led by researchers at the University of Rochester.
Researchers sought to examine the relationship between semen quality and long-term risks from growth hormones and other chemicals in beef. While the study results revealed a significant link between the lowest sperm counts and mothers who were the highest beef consumers (seven or more beef meals per week), researchers could not pinpoint hormones, pesticides or other environmental chemicals in the animal fat as a direct cause.
"What we’re really doing here is raising an issue," said Shanna H. Swan, Ph.D., director of the Center for Reproductive Epidemiology at the University of Rochester Medical Center and lead author of the study. "The average sperm concentration of the men in our study went down as their mothers’ beef intake went up. But this needs to be followed carefully before we can draw any conclusions."
The study is being published March 28 in the journal Human Reproduction.
It’s important to note that all of the 387 men in the study were able to conceive a child without medical assistance, so although sperm counts were low in some cases none of the men were actually infertile. Yet among the 51 men whose mothers were the highest beef eaters, almost 18 percent had sperm counts classified by the World Health Organization as "sub-fertile" (20 mill/ml or lower). By comparison, sperm concentrations were 24 percent higher for men whose mothers ate less beef, and only about 5 percent had sperm counts that could be classified as sub-fertile.
The concern, Swan said, is that high beef consumption by pregnant women may alter sperm production of the male fetus in utero, particularly at the end of the first trimester during the critical period for testicular development. Although sperm production occurs in stages -- prenatal, during puberty, and into adulthood – the most important stage for developing semen quality occurs in the womb, Swan added.
The study participants were part of the federally funded, multi-center Study for Future Families, a cohort of pregnant women and their partners who have agreed to provide data so that scientists can investigate environmental causes of variations in reproductive health. Swan, a professor of Obstetrics and Gynecology, has been the principal investigator of SFF since 1998. The National Institutes of Health supported this project.
Men from the SFF cohort born between 1949 and 1983 were requested to ask their mothers to complete a questionnaire about her prenatal diet. During this time period, it would have been difficult for the mothers to avoid hormone residues in beef products, as numerous chemical additives were used.
Today, anabolic hormones continue to be legal in the United States and elsewhere, although the Food and Drug Administration has defined an "acceptable daily intake" for each of the six hormones commonly used in cattle. In 1979 the FDA did withdraw approval of the use of diethylstilbestrol (DES), the first synthetic hormone, in cattle. (The European Union banned the use of growth promoters in cattle in 1988.)
Researchers studied the sons’ semen quality for movement, concentration and other properties. Then they used statistical methods to relate each man’s semen quality to the data on his mother’s diet.
Mothers who reported eating an average of more than one meal a day of beef were referred to as "high beef consumers." The average number of beef meals was 4.3 per week. Researchers also examined the mothers’ consumption of other meats (pork, lamb or veal), as well as fish, chicken, soy products and vegetables, but did not observe a significant association between sperm count and these other foods.
In addition, researchers looked at the sons’ own beef consumption, and found no association with semen quality.
Several explanations for the findings are possible, Swan said, including pesticides and other contaminants in cattle feed, as well as lifestyle factors during pregnancy that may correlate with greater beef consumption. Swan acknowledged that the mothers’ beef recall is subject to error, although pregnancy is usually a time of heightened awareness.
"This study must be replicated to confirm our findings," Swan said. "One way to determine if prenatal exposure to anabolic steroids is responsible for a change in sperm count would be to repeat this study in men born in Europe after 1988, when hormones were no longer permitted in beef sold or produced there."
Swan said she cannot advise women on how much beef is safe to eat during pregnancy. "We don’t have the numbers to identify a ‘safe cutoff,’ Swan said, "but in these data it seems to be the very high beef consumption that raises questions."
In previous studies, Swan has looked at whether semen quality is associated with exposure to farm pesticides in men from rural Missouri versus urban areas such as Minneapolis or New York. But this is the first study to examine beef intake and semen quality. A lack of human data on the safety of anabolic steroids in meat production prompted the latest analysis.
Researchers sought to examine the relationship between semen quality and long-term risks from growth hormones and other chemicals in beef. While the study results revealed a significant link between the lowest sperm counts and mothers who were the highest beef consumers (seven or more beef meals per week), researchers could not pinpoint hormones, pesticides or other environmental chemicals in the animal fat as a direct cause.
"What we’re really doing here is raising an issue," said Shanna H. Swan, Ph.D., director of the Center for Reproductive Epidemiology at the University of Rochester Medical Center and lead author of the study. "The average sperm concentration of the men in our study went down as their mothers’ beef intake went up. But this needs to be followed carefully before we can draw any conclusions."
The study is being published March 28 in the journal Human Reproduction.
It’s important to note that all of the 387 men in the study were able to conceive a child without medical assistance, so although sperm counts were low in some cases none of the men were actually infertile. Yet among the 51 men whose mothers were the highest beef eaters, almost 18 percent had sperm counts classified by the World Health Organization as "sub-fertile" (20 mill/ml or lower). By comparison, sperm concentrations were 24 percent higher for men whose mothers ate less beef, and only about 5 percent had sperm counts that could be classified as sub-fertile.
The concern, Swan said, is that high beef consumption by pregnant women may alter sperm production of the male fetus in utero, particularly at the end of the first trimester during the critical period for testicular development. Although sperm production occurs in stages -- prenatal, during puberty, and into adulthood – the most important stage for developing semen quality occurs in the womb, Swan added.
The study participants were part of the federally funded, multi-center Study for Future Families, a cohort of pregnant women and their partners who have agreed to provide data so that scientists can investigate environmental causes of variations in reproductive health. Swan, a professor of Obstetrics and Gynecology, has been the principal investigator of SFF since 1998. The National Institutes of Health supported this project.
Men from the SFF cohort born between 1949 and 1983 were requested to ask their mothers to complete a questionnaire about her prenatal diet. During this time period, it would have been difficult for the mothers to avoid hormone residues in beef products, as numerous chemical additives were used.
Today, anabolic hormones continue to be legal in the United States and elsewhere, although the Food and Drug Administration has defined an "acceptable daily intake" for each of the six hormones commonly used in cattle. In 1979 the FDA did withdraw approval of the use of diethylstilbestrol (DES), the first synthetic hormone, in cattle. (The European Union banned the use of growth promoters in cattle in 1988.)
Researchers studied the sons’ semen quality for movement, concentration and other properties. Then they used statistical methods to relate each man’s semen quality to the data on his mother’s diet.
Mothers who reported eating an average of more than one meal a day of beef were referred to as "high beef consumers." The average number of beef meals was 4.3 per week. Researchers also examined the mothers’ consumption of other meats (pork, lamb or veal), as well as fish, chicken, soy products and vegetables, but did not observe a significant association between sperm count and these other foods.
In addition, researchers looked at the sons’ own beef consumption, and found no association with semen quality.
Several explanations for the findings are possible, Swan said, including pesticides and other contaminants in cattle feed, as well as lifestyle factors during pregnancy that may correlate with greater beef consumption. Swan acknowledged that the mothers’ beef recall is subject to error, although pregnancy is usually a time of heightened awareness.
"This study must be replicated to confirm our findings," Swan said. "One way to determine if prenatal exposure to anabolic steroids is responsible for a change in sperm count would be to repeat this study in men born in Europe after 1988, when hormones were no longer permitted in beef sold or produced there."
Swan said she cannot advise women on how much beef is safe to eat during pregnancy. "We don’t have the numbers to identify a ‘safe cutoff,’ Swan said, "but in these data it seems to be the very high beef consumption that raises questions."
In previous studies, Swan has looked at whether semen quality is associated with exposure to farm pesticides in men from rural Missouri versus urban areas such as Minneapolis or New York. But this is the first study to examine beef intake and semen quality. A lack of human data on the safety of anabolic steroids in meat production prompted the latest analysis.
Higher Trans Fat Levels = Higher Risk of Heart Disease
Higher Trans Fat Levels in Blood Associated With Elevated Risk of Heart Disease
igh consumption of trans fat, found mainly in partially hydrogenated vegetable oils and widely used by the food industry, has been linked to an increased risk of coronary heart disease (CHD). New York and Philadelphia have passed measures eliminating its use in restaurants, and other cities are considering similar bans. A new study from the Harvard School of Public Health (HSPH) provides the strongest association to date between trans fat and heart disease. It found that women in the U.S. with the highest levels of trans fat in their blood had three times the risk of CHD as those with the lowest levels. The study was published online on March 26, 2007, and will appear in the April 10, 2007 print issue of Circulation: Journal of the American Heart Association.
“The strength of this study is that the amount of trans fatty acid levels was measured in blood samples from the study population. Because humans cannot synthesize trans fatty acids, the amount of trans fat in red blood cells is an excellent biomarker of trans fat intake,” said senior author Frank Hu, associate professor of nutrition and epidemiology at HSPH.
Clinical trials have shown that trans fatty acids increase LDL cholesterol and lower HDL cholesterol, making them the only class of fatty acids, which includes saturated fat, to have this dual effect. HDL (high-density lipoprotein) is considered a “good” cholesterol; LDL (low-density lipoprotein) a “bad” cholesterol.
The researchers, led by Hu and lead author Qi Sun, a graduate research assistant at HSPH, set out to test the assumption that higher trans fatty acid levels in erythrocytes—red blood cells—were associated with a higher risk of heart disease among U.S. women. Blood samples collected in 1989 and 1990 from 32,826 participants in the Brigham and Women’s Hospital-based Nurses’ Health Study were examined. During six years of follow-up, 166 cases of CHD were diagnosed and matched with 327 controls for age, smoking status, fasting status and date of blood drawing.
After adjusting for age, smoking status and other dietary and lifestyle cardiovascular risk factors, the researchers found that a higher level of trans fatty acids in red blood cells was associated with an elevated risk of CHD. The risk among women in the top quartile of trans fat levels was triple that of the lowest quartile. “Positive associations have been shown in earlier studies based on dietary data provided by the participants, but the use of biomarkers of trans fatty acids is believed to be more reliable than self-reports. This is probably the reason why we see an even stronger association between blood levels of trans fat and risk of CHD in this study,” said Sun.
“These data provide further justifications for current efforts to remove trans fat from foods and restaurant meals,” said Hu. “Trans fat intake in the U.S. is still high. Reducing trans fat intake should remain an important public health priority.”
igh consumption of trans fat, found mainly in partially hydrogenated vegetable oils and widely used by the food industry, has been linked to an increased risk of coronary heart disease (CHD). New York and Philadelphia have passed measures eliminating its use in restaurants, and other cities are considering similar bans. A new study from the Harvard School of Public Health (HSPH) provides the strongest association to date between trans fat and heart disease. It found that women in the U.S. with the highest levels of trans fat in their blood had three times the risk of CHD as those with the lowest levels. The study was published online on March 26, 2007, and will appear in the April 10, 2007 print issue of Circulation: Journal of the American Heart Association.
“The strength of this study is that the amount of trans fatty acid levels was measured in blood samples from the study population. Because humans cannot synthesize trans fatty acids, the amount of trans fat in red blood cells is an excellent biomarker of trans fat intake,” said senior author Frank Hu, associate professor of nutrition and epidemiology at HSPH.
Clinical trials have shown that trans fatty acids increase LDL cholesterol and lower HDL cholesterol, making them the only class of fatty acids, which includes saturated fat, to have this dual effect. HDL (high-density lipoprotein) is considered a “good” cholesterol; LDL (low-density lipoprotein) a “bad” cholesterol.
The researchers, led by Hu and lead author Qi Sun, a graduate research assistant at HSPH, set out to test the assumption that higher trans fatty acid levels in erythrocytes—red blood cells—were associated with a higher risk of heart disease among U.S. women. Blood samples collected in 1989 and 1990 from 32,826 participants in the Brigham and Women’s Hospital-based Nurses’ Health Study were examined. During six years of follow-up, 166 cases of CHD were diagnosed and matched with 327 controls for age, smoking status, fasting status and date of blood drawing.
After adjusting for age, smoking status and other dietary and lifestyle cardiovascular risk factors, the researchers found that a higher level of trans fatty acids in red blood cells was associated with an elevated risk of CHD. The risk among women in the top quartile of trans fat levels was triple that of the lowest quartile. “Positive associations have been shown in earlier studies based on dietary data provided by the participants, but the use of biomarkers of trans fatty acids is believed to be more reliable than self-reports. This is probably the reason why we see an even stronger association between blood levels of trans fat and risk of CHD in this study,” said Sun.
“These data provide further justifications for current efforts to remove trans fat from foods and restaurant meals,” said Hu. “Trans fat intake in the U.S. is still high. Reducing trans fat intake should remain an important public health priority.”
Nutrients might prevent hearing loss
Nutrients might prevent hearing loss, new animal study suggests
Antioxidant-mineral combination protects against damage for days after noise exposure, U-M study in guinea pigs shows
Soldiers exposed to the deafening din of battle have little defense against hearing loss, and are often reluctant to wear protective gear like ear plugs that could make them less able to react to danger. But what if a nutritious daily "candy bar" could prevent much of that potential damage to their hearing?
In a new study in animals, University of Michigan researchers report that a combination of high doses of vitamins A, C, and E and magnesium, taken one hour before noise exposure and continued as a once-daily treatment for five days, was very effective at preventing permanent noise-induced hearing loss. The animals had prolonged exposure to sounds as loud as a jet engine at take-off at close range.
Clinical trials of a hearing-protection tablet or snack bar for people could begin soon, and if successful such a product could be available in as little as two years, says Josef M. Miller, Ph.D., the senior author of the study, which is published online in the journal Free Radical Biology and Medicine. Miller is a professor in the Department of Otolaryngology at the U-M Medical School, and former director of the U-M Health System’s Kresge Hearing Research Institute, where the study was performed.
Convinced by emerging evidence that nutrients can effectively block one major factor in hearing loss after noise trauma — inner ear damage caused by excessive free radical activity — Miller has launched a U-M startup company OtoMedicine that is developing the vitamin-and-magnesium formulation.
"These agents have been used for many years, but not for hearing loss. We know they’re safe, so that opens the door to push ahead with clinical trials with confidence we’re not going to do any harm," says Miller.
The formulation the researchers used built on earlier animal studies showing that single antioxidant vitamins were somewhat effective in preventing hearing loss, and on studies of Israeli soldiers given magnesium many days prior to exposure, who gained relatively small protective effects.
In the U-M study, noise-induced hearing loss was measured in four groups of guinea pigs treated with the antioxidant vitamins A, C and E, magnesium alone, an ACE-magnesium combination, or a placebo. The treatments began one hour before a five-hour exposure to 120 decibel (dB) sound pressure level noise, and continued once daily for five days.
The group given the combined treatments of vitamins A, C and E and magnesium showed significantly less noise-induced hearing loss than all of the other groups.
"Vitamins A, C and E and magnesium worked in synergy to prevent cell damage," explains Colleen G. Le Prell, Ph.D., the study’s lead author and a research investigator at the U-M Kresge Hearing Research Institute. According to the researchers, pre-treatment presumably reduced reactive elements called free radicals that form during and after noise exposure and noise-induced constriction of blood flow to the inner ear, and may have also reduced neural excitotoxicity, or the damage to auditory neurons that can occur due to over-stimulation. The post-noise nutrient doses apparently "scavenged" free radicals that continue to form long-after after this noise exposure ends.
In the past 10 years, scientists have learned that noise-induced hearing loss occurs in part because cell mitochondria in the ear churn out damaging free radicals in response to loud sounds. "Free radical formation bursts initially, then peaks again during the days after exposure," explains Le Prell.
The antioxidant vitamins and magnesium used in the study are widely used dietary supplements, not new drugs, and therefore they don’t require the extensive safety tests required for new drug entities prior to use in clinical trials. The doses to be used in proposed human trials will be within the ranges considered safe according to the Institute of Medicine and federal nutrition guidelines.
"Ultimately, we envision soldiers would have a nutritional bar with meals and it would give them adequate daily protection," says Miller. Similar bars with other formulations are already given to soldiers to help them withstand hot weather and other war zone conditions.
"Other people would likely benefit by consuming a pill or nutritional bar before going to work in noisy environments, or attending noisy events like NASCAR races or rock concerts, or even using an iPod or other music player," says Le Prell. "Based on an earlier study with other antioxidant agents, we think this micronutrient combination will work even post-noise."
That study suggested a "morning after" treatment, that might minimize hearing damage for soldiers, musicians, pilots, construction workers and others — even if they don’t take it until after they experience dangerous noise levels. It was highlighted by the National Institutes of Health on the NIDCD website at www.nidcd.nih.gov/research/stories/archives/06/08_01_06.asp.
If effective, such pre- and post-noise treatments could have far-reaching effects. About 30 million Americans regularly experience hazardous noise levels at work and at home, according to the National Institute on Deafness and Communications Disorders. Hunting, snowmobiling, using machines such as leaf blowers, lawnmowers and power tools, and attending or playing in loud music concerts commonly expose people to dangerous noise levels. Noise levels above 85 decibels damage hearing. About 28 million Americans have some degree of hearing loss. For about a third of them, noise accounts at least in part for their loss.
The U-M study also adds strength to research efforts under way in many research centers to learn how these nutrients might be used to treat many illnesses. "Similar combinations have been very effective in preventing macular degeneration, and many of these agents have been used with Alzheimer’s and Parkinson’s diseases, stroke-like ischemia, and other conditions that involve neural degeneration," Le Prell says. "You’re always hoping as a basic scientist to find a commonality like that, across other disease processes," says Miller.
U-M has applied for patents covering the use of this unique combination of vitamins and minerals in the prevention of hearing loss, as demonstrated in this study; if and when revenues are generated as a result of these commercialization efforts, the University and the inventors of the technology stand to benefit financially
Antioxidant-mineral combination protects against damage for days after noise exposure, U-M study in guinea pigs shows
Soldiers exposed to the deafening din of battle have little defense against hearing loss, and are often reluctant to wear protective gear like ear plugs that could make them less able to react to danger. But what if a nutritious daily "candy bar" could prevent much of that potential damage to their hearing?
In a new study in animals, University of Michigan researchers report that a combination of high doses of vitamins A, C, and E and magnesium, taken one hour before noise exposure and continued as a once-daily treatment for five days, was very effective at preventing permanent noise-induced hearing loss. The animals had prolonged exposure to sounds as loud as a jet engine at take-off at close range.
Clinical trials of a hearing-protection tablet or snack bar for people could begin soon, and if successful such a product could be available in as little as two years, says Josef M. Miller, Ph.D., the senior author of the study, which is published online in the journal Free Radical Biology and Medicine. Miller is a professor in the Department of Otolaryngology at the U-M Medical School, and former director of the U-M Health System’s Kresge Hearing Research Institute, where the study was performed.
Convinced by emerging evidence that nutrients can effectively block one major factor in hearing loss after noise trauma — inner ear damage caused by excessive free radical activity — Miller has launched a U-M startup company OtoMedicine that is developing the vitamin-and-magnesium formulation.
"These agents have been used for many years, but not for hearing loss. We know they’re safe, so that opens the door to push ahead with clinical trials with confidence we’re not going to do any harm," says Miller.
The formulation the researchers used built on earlier animal studies showing that single antioxidant vitamins were somewhat effective in preventing hearing loss, and on studies of Israeli soldiers given magnesium many days prior to exposure, who gained relatively small protective effects.
In the U-M study, noise-induced hearing loss was measured in four groups of guinea pigs treated with the antioxidant vitamins A, C and E, magnesium alone, an ACE-magnesium combination, or a placebo. The treatments began one hour before a five-hour exposure to 120 decibel (dB) sound pressure level noise, and continued once daily for five days.
The group given the combined treatments of vitamins A, C and E and magnesium showed significantly less noise-induced hearing loss than all of the other groups.
"Vitamins A, C and E and magnesium worked in synergy to prevent cell damage," explains Colleen G. Le Prell, Ph.D., the study’s lead author and a research investigator at the U-M Kresge Hearing Research Institute. According to the researchers, pre-treatment presumably reduced reactive elements called free radicals that form during and after noise exposure and noise-induced constriction of blood flow to the inner ear, and may have also reduced neural excitotoxicity, or the damage to auditory neurons that can occur due to over-stimulation. The post-noise nutrient doses apparently "scavenged" free radicals that continue to form long-after after this noise exposure ends.
In the past 10 years, scientists have learned that noise-induced hearing loss occurs in part because cell mitochondria in the ear churn out damaging free radicals in response to loud sounds. "Free radical formation bursts initially, then peaks again during the days after exposure," explains Le Prell.
The antioxidant vitamins and magnesium used in the study are widely used dietary supplements, not new drugs, and therefore they don’t require the extensive safety tests required for new drug entities prior to use in clinical trials. The doses to be used in proposed human trials will be within the ranges considered safe according to the Institute of Medicine and federal nutrition guidelines.
"Ultimately, we envision soldiers would have a nutritional bar with meals and it would give them adequate daily protection," says Miller. Similar bars with other formulations are already given to soldiers to help them withstand hot weather and other war zone conditions.
"Other people would likely benefit by consuming a pill or nutritional bar before going to work in noisy environments, or attending noisy events like NASCAR races or rock concerts, or even using an iPod or other music player," says Le Prell. "Based on an earlier study with other antioxidant agents, we think this micronutrient combination will work even post-noise."
That study suggested a "morning after" treatment, that might minimize hearing damage for soldiers, musicians, pilots, construction workers and others — even if they don’t take it until after they experience dangerous noise levels. It was highlighted by the National Institutes of Health on the NIDCD website at www.nidcd.nih.gov/research/stories/archives/06/08_01_06.asp.
If effective, such pre- and post-noise treatments could have far-reaching effects. About 30 million Americans regularly experience hazardous noise levels at work and at home, according to the National Institute on Deafness and Communications Disorders. Hunting, snowmobiling, using machines such as leaf blowers, lawnmowers and power tools, and attending or playing in loud music concerts commonly expose people to dangerous noise levels. Noise levels above 85 decibels damage hearing. About 28 million Americans have some degree of hearing loss. For about a third of them, noise accounts at least in part for their loss.
The U-M study also adds strength to research efforts under way in many research centers to learn how these nutrients might be used to treat many illnesses. "Similar combinations have been very effective in preventing macular degeneration, and many of these agents have been used with Alzheimer’s and Parkinson’s diseases, stroke-like ischemia, and other conditions that involve neural degeneration," Le Prell says. "You’re always hoping as a basic scientist to find a commonality like that, across other disease processes," says Miller.
U-M has applied for patents covering the use of this unique combination of vitamins and minerals in the prevention of hearing loss, as demonstrated in this study; if and when revenues are generated as a result of these commercialization efforts, the University and the inventors of the technology stand to benefit financially
Monday, March 26, 2007
Cocoa (dark chocolate) heart benefits
Effects of Sustained Ingestion of Cocoa on Endothelial Function in Adults
Flavonoids, a group of antioxidant compounds found in fruits and vegetables, are not generally labeled as essential nutrients, but play an important role in maintaining one's health. In fact, studies indicate that there is a strong inverse correlation between the consumption of foods rich in flavonoids – such as wine, green tea, fruits and vegetables – and cardiovascular disease. Cocoa or dark chocolate products are considered one of the most concentrated sources of flavonoids among commonly consumed foods. Since endothelial function has been used extensively to evaluate the effects of foods and nutrients on cardiac risk, researchers at the Yale Prevention Research Center in Connecticut conducted a trial to assess whether the consumption of cocoa would provide any sustained benefits on endothelial function.
Specifically, the team measured the function of the brachial artery to relax and expand to accommodate increased blood flow (also know as flow mediated dilation, or FMD) in adults with a body mass index (BMI) between 25 and 35 kg/m2. In the randomized, single-blind, placebo-controlled crossover study, 45 subjects recruited from the general population of southwestern Connecticut were randomly assigned to one of the three consumption groups: eight ounces of either cocoa without sugar, cocoa with sugar or placebo. For six weeks, all participants underwent endothelial function testing, assessing FMD of the brachial artery using high frequency ultrasound before and after the daily cocoa or placebo consumption.
Cocoa was considered a successful vehicle to improve endothelial function in this trial. Of the 39 subjects who completed the trial, FMD improved significantly in the groups consuming cocoa with no sugar (2.4 %) and cocoa with sugar (1.5 %) from baseline values when compared to placebo (-0.8 %).
"In this sample of healthy adults with BMI between 25 and 35 kg/m2, dark chocolate ingestion over a short period of time was shown to significantly improve endothelial function, leading our team to believe that greater benefit may be seen through a long-term, randomized clinical trial," said Valentine Yanchou Njike, M.D., of Yale Prevention Research Center, and co-investigator on this study. "While the findings from this study do not suggest that people should start eating more chocolate as part of their daily routine, it does suggest that we pay more attention to how dark chocolate and other flavonoid-rich foods might offer cardiovascular benefits."
Flavonoids, a group of antioxidant compounds found in fruits and vegetables, are not generally labeled as essential nutrients, but play an important role in maintaining one's health. In fact, studies indicate that there is a strong inverse correlation between the consumption of foods rich in flavonoids – such as wine, green tea, fruits and vegetables – and cardiovascular disease. Cocoa or dark chocolate products are considered one of the most concentrated sources of flavonoids among commonly consumed foods. Since endothelial function has been used extensively to evaluate the effects of foods and nutrients on cardiac risk, researchers at the Yale Prevention Research Center in Connecticut conducted a trial to assess whether the consumption of cocoa would provide any sustained benefits on endothelial function.
Specifically, the team measured the function of the brachial artery to relax and expand to accommodate increased blood flow (also know as flow mediated dilation, or FMD) in adults with a body mass index (BMI) between 25 and 35 kg/m2. In the randomized, single-blind, placebo-controlled crossover study, 45 subjects recruited from the general population of southwestern Connecticut were randomly assigned to one of the three consumption groups: eight ounces of either cocoa without sugar, cocoa with sugar or placebo. For six weeks, all participants underwent endothelial function testing, assessing FMD of the brachial artery using high frequency ultrasound before and after the daily cocoa or placebo consumption.
Cocoa was considered a successful vehicle to improve endothelial function in this trial. Of the 39 subjects who completed the trial, FMD improved significantly in the groups consuming cocoa with no sugar (2.4 %) and cocoa with sugar (1.5 %) from baseline values when compared to placebo (-0.8 %).
"In this sample of healthy adults with BMI between 25 and 35 kg/m2, dark chocolate ingestion over a short period of time was shown to significantly improve endothelial function, leading our team to believe that greater benefit may be seen through a long-term, randomized clinical trial," said Valentine Yanchou Njike, M.D., of Yale Prevention Research Center, and co-investigator on this study. "While the findings from this study do not suggest that people should start eating more chocolate as part of their daily routine, it does suggest that we pay more attention to how dark chocolate and other flavonoid-rich foods might offer cardiovascular benefits."
Black raspberries prevent cancer of esophagus, colon?
Black raspberries show promise for preventing cancer of the esophagus, colon — Using animal models (rodents) of cancer development, researchers at Ohio State University showed that animals whose diets were supplemented with black raspberries had a 60 percent reduction in tumors of the esophagus and up to an 80 percent reduction in colon tumors. Clinical trials are now underway to determine whether the berries will prevent the development of esophageal and colon cancer in humans, says study leader Gary D. Stoner, Ph.D., a researcher and professor of internal medicine at the university
Grape seeds may prevent skin cancer
Grape seed compounds may prevent skin cancer by boosting immune system
Chemicals obtained from grape seed extract show promise in animal studies as a way to prevent sunlight-induced skin cancer when used as a dietary supplement, according to researchers at the University of Alabama in Birmingham. In studies using mouse models of ultraviolet-light-induced (non-melanoma) skin cancer, mice that were fed diets supplemented with the grape seed compounds, a group of antioxidants called proanthocyanidins, showed a reduction in tumor number (up to 65 percent fewer) and size (up to 78 percent smaller) in comparison to control animals that did not receive the compounds, the researchers say. The compounds appear to work by inhibiting suppression of the immune system caused by ultraviolet light exposure, says Santosh Katiyar, Ph.D., an associate professor in the university’s department of dermatology.
Chemicals obtained from grape seed extract show promise in animal studies as a way to prevent sunlight-induced skin cancer when used as a dietary supplement, according to researchers at the University of Alabama in Birmingham. In studies using mouse models of ultraviolet-light-induced (non-melanoma) skin cancer, mice that were fed diets supplemented with the grape seed compounds, a group of antioxidants called proanthocyanidins, showed a reduction in tumor number (up to 65 percent fewer) and size (up to 78 percent smaller) in comparison to control animals that did not receive the compounds, the researchers say. The compounds appear to work by inhibiting suppression of the immune system caused by ultraviolet light exposure, says Santosh Katiyar, Ph.D., an associate professor in the university’s department of dermatology.
High-fiber foods show promise against prostate cancer
Compound found in high-fiber foods shows promise against prostate cancer
A dietary component found in most whole grain foods, beans, nuts and other high-fiber items shows promise in animal studies as a potent weapon for preventing prostate cancer. The compound, inositol hexaphosphate (IP6), was fed to animal models of prostate cancer and resulted in up to a 66 percent reduction in tumor size in comparison to control animals that were given water instead, the researchers say. The compound, which is sold in stores as a dietary supplement, adds to a growing number of products — including lycopene, milk thistle extract, vitamin E and selenium — that also have shown promise against prostate cancer, says Rajesh Agarwal, Ph.D., a professor in the Department of Pharmaceutical Sciences at the University of Colorado Health Sciences Center in Denver.
A dietary component found in most whole grain foods, beans, nuts and other high-fiber items shows promise in animal studies as a potent weapon for preventing prostate cancer. The compound, inositol hexaphosphate (IP6), was fed to animal models of prostate cancer and resulted in up to a 66 percent reduction in tumor size in comparison to control animals that were given water instead, the researchers say. The compound, which is sold in stores as a dietary supplement, adds to a growing number of products — including lycopene, milk thistle extract, vitamin E and selenium — that also have shown promise against prostate cancer, says Rajesh Agarwal, Ph.D., a professor in the Department of Pharmaceutical Sciences at the University of Colorado Health Sciences Center in Denver.
Unfiltered apple juice daily may prevent colon cancer
Researchers in Germany say that drinking two to three glasses of cloudy apple juice (unfiltered) per day may help keep colon cancer at bay. In a ten-week study using a mouse model for colon cancer, animals that were fed either cloudy apple juice or a potent extract of the juice showed a 38 percent and 40 percent reduction (respectively) in benign tumors of the small intestine, an indicator of its potential to fight colon cancer, in comparison to control animals that were given water instead of juice, according to Clarissa Gerhäuser, Ph.D., a researcher with the German Cancer Research Center in Heidelberg. The anticancer effect is likely due to a potent class of antioxidants called procyanidins, the researcher says. A widely publicized recent study by a group of researchers in Poland found that cloudy apple juice also is richer in antioxidants — up to four times higher — than clear apple juice.
Blueberries help prevent colon cancer
Blueberries contain chemical that may help prevent colon cancer
A compound found in blueberries shows promise of preventing colon cancer in animals, according to a joint study by scientists at Rutgers University and the U.S. Department of Agriculture. The compound, pterostilbene, is a potent antioxidant that could be developed into a pill with the potential for fewer side effects than some commercial drugs that are currently used to prevent the disease. Colon cancer is considered the second leading cause of cancer death in the United States, the researchers say.
While recent studies have identified a growing number of antioxidants in fruits, vegetables and whole grains that show potential for fighting colon cancer, this is believed to be the first study to demonstrate the cancer-fighting potential of pterostilbene against the disease, the scientists say. Their findings were described today at the 233rd national meeting of the American Chemical Society. March is National Colorectal Cancer Awareness Month.
“This study underscores the need to include more berries in the diet, especially blueberries,” says study leader Bandaru Reddy, Ph.D., a professor in the Department of Chemical Biology at Rutgers in Piscataway, N.J. Although the blueberry compound won’t cure colon cancer, it represents a potential new and attractive strategy for preventing the disease naturally, says Reddy, a leading expert on nutritional factors that influence colon cancer development.
Along with scientists Nanjoo Suh, also of Rutgers, and Agnes Rimando of the USDA’s Agricultural Research Service (ARS), Reddy and his associates conducted a small pilot study to determine the effect of pterostilbene on colon cancer. The study included 18 rats that were given a compound (azoxymethane) to induce colon cancer in a manner similar to human colon cancer development. Nine of the animals were then placed on a balanced daily diet, while the other nine were given the same diet supplemented with pterostilbene (at a level of 40 parts per million).
At the end of an eight-week study period, the rats that were fed pterostilbene showed 57 percent fewer pre-cancerous lesions in their colon in comparison to the control group, Reddy and his associates say. Pterostilbene also reduced colonic cell proliferation and inhibited certain genes involved in inflammation, both of which are considered colon cancer risk factors, the researchers say.
Although researchers still do not know the exact cause of colon cancer, the disease has been linked to a high intake of saturated fats and calories, particularly in Western diets. Pterostilbene may be able to reverse this process, possibly by lowering lipids, Reddy says. He cites a recent study by co-author Agnes Rimando, a research chemist at the USDA-ARS, who demonstrated in cell and animal studies that pterostilbene is capable of lowering cholesterol levels. In a related paper also being presented at the ACS national meeting, Rimando demonstrated that blueberries, particularly their skins, can lower cholesterol when fed to animals (see AGFD 038 reference below). More studies on the mechanism of action of pterostilbene are needed, the researchers note.
Reddy recently demonstrated that certain COX-2 inhibitors, anti-inflammatory drugs that are used for pain and arthritis, were capable of preventing colon cancer in animals. But studies by others have shown that COX-2 inhibitors also can increase the risk of heart attacks and strokes when used in high doses. Combining pterostilbene with these COX-2 drugs could allow them to be used in lower doses, reducing their risk of adverse side effects, Reddy says. More studies are needed to determine the compound’s efficacy and potential for toxicity, he notes.
Pterostilbene is an antioxidant that is similar to resveratrol, an antioxidant identified in grapes and red wine that also is recognized for its anticancer properties. Pterostilbene also is found in grapes, but it is more abundant in blueberries, the researchers say.
In studies by other researchers, blueberries also have shown promise for protecting against memory loss and heart disease. In general, a diet rich in fruits, vegetables and grain is recommended by health experts for the prevention of colon cancer. Funding for this study was provided by the National Cancer Institute.
A compound found in blueberries shows promise of preventing colon cancer in animals, according to a joint study by scientists at Rutgers University and the U.S. Department of Agriculture. The compound, pterostilbene, is a potent antioxidant that could be developed into a pill with the potential for fewer side effects than some commercial drugs that are currently used to prevent the disease. Colon cancer is considered the second leading cause of cancer death in the United States, the researchers say.
While recent studies have identified a growing number of antioxidants in fruits, vegetables and whole grains that show potential for fighting colon cancer, this is believed to be the first study to demonstrate the cancer-fighting potential of pterostilbene against the disease, the scientists say. Their findings were described today at the 233rd national meeting of the American Chemical Society. March is National Colorectal Cancer Awareness Month.
“This study underscores the need to include more berries in the diet, especially blueberries,” says study leader Bandaru Reddy, Ph.D., a professor in the Department of Chemical Biology at Rutgers in Piscataway, N.J. Although the blueberry compound won’t cure colon cancer, it represents a potential new and attractive strategy for preventing the disease naturally, says Reddy, a leading expert on nutritional factors that influence colon cancer development.
Along with scientists Nanjoo Suh, also of Rutgers, and Agnes Rimando of the USDA’s Agricultural Research Service (ARS), Reddy and his associates conducted a small pilot study to determine the effect of pterostilbene on colon cancer. The study included 18 rats that were given a compound (azoxymethane) to induce colon cancer in a manner similar to human colon cancer development. Nine of the animals were then placed on a balanced daily diet, while the other nine were given the same diet supplemented with pterostilbene (at a level of 40 parts per million).
At the end of an eight-week study period, the rats that were fed pterostilbene showed 57 percent fewer pre-cancerous lesions in their colon in comparison to the control group, Reddy and his associates say. Pterostilbene also reduced colonic cell proliferation and inhibited certain genes involved in inflammation, both of which are considered colon cancer risk factors, the researchers say.
Although researchers still do not know the exact cause of colon cancer, the disease has been linked to a high intake of saturated fats and calories, particularly in Western diets. Pterostilbene may be able to reverse this process, possibly by lowering lipids, Reddy says. He cites a recent study by co-author Agnes Rimando, a research chemist at the USDA-ARS, who demonstrated in cell and animal studies that pterostilbene is capable of lowering cholesterol levels. In a related paper also being presented at the ACS national meeting, Rimando demonstrated that blueberries, particularly their skins, can lower cholesterol when fed to animals (see AGFD 038 reference below). More studies on the mechanism of action of pterostilbene are needed, the researchers note.
Reddy recently demonstrated that certain COX-2 inhibitors, anti-inflammatory drugs that are used for pain and arthritis, were capable of preventing colon cancer in animals. But studies by others have shown that COX-2 inhibitors also can increase the risk of heart attacks and strokes when used in high doses. Combining pterostilbene with these COX-2 drugs could allow them to be used in lower doses, reducing their risk of adverse side effects, Reddy says. More studies are needed to determine the compound’s efficacy and potential for toxicity, he notes.
Pterostilbene is an antioxidant that is similar to resveratrol, an antioxidant identified in grapes and red wine that also is recognized for its anticancer properties. Pterostilbene also is found in grapes, but it is more abundant in blueberries, the researchers say.
In studies by other researchers, blueberries also have shown promise for protecting against memory loss and heart disease. In general, a diet rich in fruits, vegetables and grain is recommended by health experts for the prevention of colon cancer. Funding for this study was provided by the National Cancer Institute.
Grapefruit/Orange diet has hearty perks
Grapefruit diet has hearty perks
Compounds in grapefruit and oranges have been shown to lower cholesterol levels in the blood. Two flavanones, hesperidin and naringin, were extracted from citrus fruits and fed to rats split into groups with some receiving high levels of cholesterol in their diet. Shela Gorinstein of The Hebrew University in Jerusalem found that after 30 days cholesterol levels in rats' blood reduced by around 20-25% in those fed a cholesterol-rich diet (Journal of the Science of Food and Agriculture DOI: 10.1002/jsfa.2834). David Bender, Sub-dean at the Royal Free and University College Medical School, London, believes that the results show a significant reduction in the increase in plasma lipids caused by cholesterol feeding. "This is potentially beneficial to health with regards to heart disease", he added.
Compounds in grapefruit and oranges have been shown to lower cholesterol levels in the blood. Two flavanones, hesperidin and naringin, were extracted from citrus fruits and fed to rats split into groups with some receiving high levels of cholesterol in their diet. Shela Gorinstein of The Hebrew University in Jerusalem found that after 30 days cholesterol levels in rats' blood reduced by around 20-25% in those fed a cholesterol-rich diet (Journal of the Science of Food and Agriculture DOI: 10.1002/jsfa.2834). David Bender, Sub-dean at the Royal Free and University College Medical School, London, believes that the results show a significant reduction in the increase in plasma lipids caused by cholesterol feeding. "This is potentially beneficial to health with regards to heart disease", he added.
Organic Kiwis Better For Health
In one of the most comprehensive and definitive studies of its kind to date, a team of researchers at the University of California, Davis have proven that organically grown kiwifruit contain more health-promoting factors than those grown under conventional conditions. The research is reported in the SCI’s magazine Chemistry & Industry. The debate over the relative health benefits of organic versus conventional food has raged for years, with UK environment secretary David Miliband declaring in January that buying organic is just a lifestyle choice.
The Davis scientists, led by Drs. Maria Amodio and Adel Kader, showed that organically grown kiwifruit had significantly increased levels of polyphenols, the healthy compounds found in red wine and coloured berries. They also had a higher overall antioxidant activity, as well as higher levels of ascorbic acid (vitamin C) and important minerals compared with their conventionally grown counterparts (Journal of the Science of Food and Agriculture DOI 10.1002/jsfa.2820). Their work differed to previously inconclusive studies, as they were able to compare like-for-like with kiwis grown next to each other on the same farm at the same time, in the same environmental conditions. Kader added: “[previous] studies did not include phenolic compounds in the comparison.”
The two categories of kiwifruit showed other differences which Kadel believes are most likely due to the fruits having to be able to survive against pests in the absence of pesticides. For example, organic kiwis had thicker skins, which could help the fruits resist insects, and higher antioxidant activity which is thought to be a natural by-product of stress.
However, some people are still unsure about the potential benefits of antioxidants and other compounds elevated in organic farm produce. Carl Winter, director of the FoodSafe Program at UC Davies, asks whether these increases in nutrients and antioxidants are of any appreciable health perspective. He is also concerned about any unknown negative effects on the health. “The authors also did not look for any plant secondary metabolites of potential toxicological impact.”
According to the Soil Association, organic food sales in the UK increased by 30% to £1.6bn in 2006. The world market for certified organic foods was estimated to be worth US $23-25 billion in 2003 and is growing approximately 19% every year, making these products the fastest-growing sector of the global food industry.
The Davis scientists, led by Drs. Maria Amodio and Adel Kader, showed that organically grown kiwifruit had significantly increased levels of polyphenols, the healthy compounds found in red wine and coloured berries. They also had a higher overall antioxidant activity, as well as higher levels of ascorbic acid (vitamin C) and important minerals compared with their conventionally grown counterparts (Journal of the Science of Food and Agriculture DOI 10.1002/jsfa.2820). Their work differed to previously inconclusive studies, as they were able to compare like-for-like with kiwis grown next to each other on the same farm at the same time, in the same environmental conditions. Kader added: “[previous] studies did not include phenolic compounds in the comparison.”
The two categories of kiwifruit showed other differences which Kadel believes are most likely due to the fruits having to be able to survive against pests in the absence of pesticides. For example, organic kiwis had thicker skins, which could help the fruits resist insects, and higher antioxidant activity which is thought to be a natural by-product of stress.
However, some people are still unsure about the potential benefits of antioxidants and other compounds elevated in organic farm produce. Carl Winter, director of the FoodSafe Program at UC Davies, asks whether these increases in nutrients and antioxidants are of any appreciable health perspective. He is also concerned about any unknown negative effects on the health. “The authors also did not look for any plant secondary metabolites of potential toxicological impact.”
According to the Soil Association, organic food sales in the UK increased by 30% to £1.6bn in 2006. The world market for certified organic foods was estimated to be worth US $23-25 billion in 2003 and is growing approximately 19% every year, making these products the fastest-growing sector of the global food industry.
Study shows fruit juice/drink link to weight gain
Australian schoolchildren who drink fruit juices and fruit drinks are more likely to be overweight or obese than those who don't, Deakin researchers have found.
In a study* of children aged four to 12 years from the Barwon South Western region researchers Andrea Sanigorski, Colin Bell and Boyd Swinburn from the University's Faculty of Health, Medicine, Nursing and Behavioural Sciences found that children who had drank more than two glasses (500ml) of fruit juice/drink per day were more likely to be overweight or obese.
"These odds increased as the amounts of fruit juice/drink consumed increased," Dr Sanigorski said.
"Children who drank more than three glasses of soft drink (three quarters of a litre/750ml) or 4 glasses of fruit juice/drinks (1 litre) on the day in question were more than twice as likely to be overweight or obese compared with children who did not drink these drinks."
Dr Sanigorski said the study's findings were consistent with those found in children in the United States and the United Kingdom.
Parents unaware
"Soft drink in this study was not the biggest issue," she said. "The data would appear to show primary school children do not regularly drink a lot of soft drink, however parents may not be aware that regular and large amounts of fruit drinks, fruit juices and fruit cordials can also be bad for children's long term health.
"These drinks contribute high amounts of energy to kids' diets', yet they don't make them feel full."
Dr Sanigorski said the study had also shown that children ate high amounts of snack food. "Although the study did not demonstrate any link to weight gain with these foods, these snacks often contain high amounts of fat, salt and sugar, and their consumption may displace other more nutritious food in the diet," she said.
"These snacks are conveniently designed to fit into lunch boxes and easily carried to school and consumed by children.
Healthier alternative
"Parents need to consider more healthy alternatives to both sweetened drinks and snack foods, and children's environments, such as preschools and schools, need to be supportive also.
"One such alternative could be as simple as a piece of fruit. Not only is it nutrient rich, but it provides fibre and can keep children fuller for longer."
Dr Sanigorski said the study had underlined the importance of the evening meal in relation to children's intake of vegetables.
"One in five children ate no vegetables at all on the day in question. Previous studies have shown that vegetable consumption occurs outside of school, mainly at home. "We need to try to get vegetables into children's diets throughout the day. Current recommendations for changes to school canteens are great because they try to increase vegetables eaten at school through wraps and the like. Otherwise there is a heavy reliance on the evening meal to provide the recommended number of vegetables in the children's diet."
In a study* of children aged four to 12 years from the Barwon South Western region researchers Andrea Sanigorski, Colin Bell and Boyd Swinburn from the University's Faculty of Health, Medicine, Nursing and Behavioural Sciences found that children who had drank more than two glasses (500ml) of fruit juice/drink per day were more likely to be overweight or obese.
"These odds increased as the amounts of fruit juice/drink consumed increased," Dr Sanigorski said.
"Children who drank more than three glasses of soft drink (three quarters of a litre/750ml) or 4 glasses of fruit juice/drinks (1 litre) on the day in question were more than twice as likely to be overweight or obese compared with children who did not drink these drinks."
Dr Sanigorski said the study's findings were consistent with those found in children in the United States and the United Kingdom.
Parents unaware
"Soft drink in this study was not the biggest issue," she said. "The data would appear to show primary school children do not regularly drink a lot of soft drink, however parents may not be aware that regular and large amounts of fruit drinks, fruit juices and fruit cordials can also be bad for children's long term health.
"These drinks contribute high amounts of energy to kids' diets', yet they don't make them feel full."
Dr Sanigorski said the study had also shown that children ate high amounts of snack food. "Although the study did not demonstrate any link to weight gain with these foods, these snacks often contain high amounts of fat, salt and sugar, and their consumption may displace other more nutritious food in the diet," she said.
"These snacks are conveniently designed to fit into lunch boxes and easily carried to school and consumed by children.
Healthier alternative
"Parents need to consider more healthy alternatives to both sweetened drinks and snack foods, and children's environments, such as preschools and schools, need to be supportive also.
"One such alternative could be as simple as a piece of fruit. Not only is it nutrient rich, but it provides fibre and can keep children fuller for longer."
Dr Sanigorski said the study had underlined the importance of the evening meal in relation to children's intake of vegetables.
"One in five children ate no vegetables at all on the day in question. Previous studies have shown that vegetable consumption occurs outside of school, mainly at home. "We need to try to get vegetables into children's diets throughout the day. Current recommendations for changes to school canteens are great because they try to increase vegetables eaten at school through wraps and the like. Otherwise there is a heavy reliance on the evening meal to provide the recommended number of vegetables in the children's diet."
Create healthier pizza by boosting antioxidants in doug
Chemists create healthier pizza by boosting antioxidants in dough
n an effort to improve health, many popular foods are undergoing a more nutritious make-over. Now, a team of food chemists at the University of Maryland has discovered how to boost the antioxidant content of pizza dough by optimizing baking and fermentation methods, a finding that could lead to healthier pizza, they say.
Pizza bakers have known for some time that longer-baking times and higher temperatures can enhance the flavor of pizza. The new study shows that these intense baking conditions also may boost antioxidant levels in dough, especially whole wheat varieties, the researchers say. Their findings were presented today at the 233rd national meeting of the American Chemical Society.
That’s good news for fans of deep-dish, Chicago-style pizza, whose longer baking time and thicker crust “may have the potential to deliver higher levels of antioxidants in comparison to other pizza styles,” says study co-author Jeffrey Moore, a doctoral student in food chemistry at the University of Maryland, College Park. Diets rich in antioxidants are thought to reduce the risk of cancer and heart disease.
“We chose to investigate pizza dough because it’s one of the most popular wheat-based food products in the U.S.,” says Moore. “Making popular food more healthy using the tools of chemistry may have a larger impact on public health.”
The study is part of an ongoing effort by researchers at the university to discover and develop new technologies that enhance the levels of natural antioxidants in grain-based food ingredients such as whole wheat flour. That effort is lead by Liangli Lucy Yu, Ph.D., an associate professor of food chemistry at the school and Moore’s graduate advisor.
To demonstrate the effect of different baking conditions on the antioxidant levels in pizza dough, Moore exposed whole grain pizza dough from two different varieties of wheat to different baking temperatures, from 400 to 550 degrees Fahrenheit, and to different baking times, from 7 to 14 minutes. A number of tests were used to measure changes in antioxidant properties.
Longer baking times or higher temperatures generally corresponded to higher levels of antioxidants in comparison to less intense baking conditions, Moore found. Antioxidant levels increased by as much as 60 percent during longer baking times and by as much as 82 percent during higher baking temperatures, depending on the type of wheat flour and the antioxidant test used, the researcher says. The exact mechanisms involved are not yet fully understood, he says.
Both baking time and temperature can be increased together at the same without burning the pizza, according to Moore, if the process is monitored carefully.
As pizza dough is often allowed to ferment before baking, Moore tested the effect of different fermentation times, ranging from zero to 48 hours, on antioxidant properties. Longer fermentation times also boosted antioxidant levels, in some cases by as much as 100 percent, he says. The increase likely resulted from chemical reactions induced by yeasts, which had more time to release the antioxidant components that were bound in the dough, Moore says.
Although only whole wheat pizza was used in this study, it is possible that these same cooking factors — longer baking time, higher temperature and longer fermentation — also will have an antioxidant boosting effect on refined pizza dough, but the effect will likely be less obvious, Moore says. That’s because most of the antioxidants in wheat are found in the bran and endosperm components, which have been largely removed in refined flour, he says.
n an effort to improve health, many popular foods are undergoing a more nutritious make-over. Now, a team of food chemists at the University of Maryland has discovered how to boost the antioxidant content of pizza dough by optimizing baking and fermentation methods, a finding that could lead to healthier pizza, they say.
Pizza bakers have known for some time that longer-baking times and higher temperatures can enhance the flavor of pizza. The new study shows that these intense baking conditions also may boost antioxidant levels in dough, especially whole wheat varieties, the researchers say. Their findings were presented today at the 233rd national meeting of the American Chemical Society.
That’s good news for fans of deep-dish, Chicago-style pizza, whose longer baking time and thicker crust “may have the potential to deliver higher levels of antioxidants in comparison to other pizza styles,” says study co-author Jeffrey Moore, a doctoral student in food chemistry at the University of Maryland, College Park. Diets rich in antioxidants are thought to reduce the risk of cancer and heart disease.
“We chose to investigate pizza dough because it’s one of the most popular wheat-based food products in the U.S.,” says Moore. “Making popular food more healthy using the tools of chemistry may have a larger impact on public health.”
The study is part of an ongoing effort by researchers at the university to discover and develop new technologies that enhance the levels of natural antioxidants in grain-based food ingredients such as whole wheat flour. That effort is lead by Liangli Lucy Yu, Ph.D., an associate professor of food chemistry at the school and Moore’s graduate advisor.
To demonstrate the effect of different baking conditions on the antioxidant levels in pizza dough, Moore exposed whole grain pizza dough from two different varieties of wheat to different baking temperatures, from 400 to 550 degrees Fahrenheit, and to different baking times, from 7 to 14 minutes. A number of tests were used to measure changes in antioxidant properties.
Longer baking times or higher temperatures generally corresponded to higher levels of antioxidants in comparison to less intense baking conditions, Moore found. Antioxidant levels increased by as much as 60 percent during longer baking times and by as much as 82 percent during higher baking temperatures, depending on the type of wheat flour and the antioxidant test used, the researcher says. The exact mechanisms involved are not yet fully understood, he says.
Both baking time and temperature can be increased together at the same without burning the pizza, according to Moore, if the process is monitored carefully.
As pizza dough is often allowed to ferment before baking, Moore tested the effect of different fermentation times, ranging from zero to 48 hours, on antioxidant properties. Longer fermentation times also boosted antioxidant levels, in some cases by as much as 100 percent, he says. The increase likely resulted from chemical reactions induced by yeasts, which had more time to release the antioxidant components that were bound in the dough, Moore says.
Although only whole wheat pizza was used in this study, it is possible that these same cooking factors — longer baking time, higher temperature and longer fermentation — also will have an antioxidant boosting effect on refined pizza dough, but the effect will likely be less obvious, Moore says. That’s because most of the antioxidants in wheat are found in the bran and endosperm components, which have been largely removed in refined flour, he says.
Long-term aspirin = reduced risk of dying in women?
Long-term aspirin use associated with reduced risk of dying in women
Women who take low to moderate doses of aspirin have a reduced risk of death from any cause, and especially heart disease–related deaths, according to a report in the March 26 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Some studies have provided evidence that aspirin may reduce the risk of heart disease and some types of cancer, the two leading causes of death in U.S. women, according to background information in the article. However, it is unclear whether aspirin reduces the risk of death overall for women.
Andrew T. Chan, M.D., M.P.H., Massachusetts General Hospital and Harvard Medical School, Boston, and colleagues examined the association between aspirin use and death in 79,439 women enrolled in the Nurses’ Health Study, a large group of female nurses who have been followed since 1976. Beginning in 1980 and again every two years through 2004, the women were asked if they used aspirin regularly and if so, how many tablets they typically took per week. At the beginning of the study, the women had no history of cardiovascular disease or cancer.
A total of 45,305 women did not use aspirin; 29,132 took low to moderate doses (one to 14 standard 325-milligram tablets of aspirin per week); and 5,002 took more than 14 tablets per week. By June 1, 2004, 9,477 of the women had died, 1,991 of heart disease and 4,469 of cancer. Women who reported using aspirin currently had a 25 percent lower risk of death from any cause than women who never used aspirin regularly. The association was stronger for death from cardiovascular disease (women who used aspirin had a 38 percent lower risk) than for death from cancer (women who used aspirin had a 12 percent lower risk).
"Use of aspirin for one to five years was associated with significant reductions in cardiovascular mortality," the authors write. "In contrast, a significant reduction in risk of cancer deaths was not observed until after 10 years of aspirin use. The benefit associated with aspirin was confined to low and moderate doses and was significantly greater in older participants and those with more cardiac risk factors."
There are several mechanisms by which aspirin could reduce the risk of death, the authors note. "Aspirin therapy may influence cardiovascular disease and cancer through its effect on common pathogenic pathways such as inflammation, insulin resistance, oxidative stress [damage to the cells caused by oxygen exposure] and cyclooxygenase (COX) enzyme activity," also linked to inflammation, they write.
Because the study looked at women who made the decision themselves whether or not to take aspirin, as opposed to a clinical trial where women are randomly assigned to aspirin or a placebo, the results do not suggest that all women should take aspirin. "Nevertheless, these data support a need for continued investigation of the use of aspirin for chronic disease prevention," the authors conclude.
These findings differ from the results of other studies regarding the benefits of aspirin use in healthy women, leaving confusion about aspirin’s role, writes John A. Baron, M.D., Dartmouth Medical School, Lebanon, N.H., in an accompanying editorial.
Dr. Baron points out that in the Women’s Health Study, researchers followed almost 40,000 women for 11 years and did not find any reduced risk of cardiovascular or other death associated with aspirin therapy, in contrast to the dramatic risk reduction seen in the Nurses’ Health Study. "Is aspirin really that good or is there some other explanation for the findings that differ so much from those of the WHS and other primary prevention trials?" he writes.
"The difference between the NHS and the aggregated data from the WHS and other trials is too large to be explained by potential weaknesses in the randomized studies," Dr. Baron writes. "At the same time, one has to consider that the observational NHS may not have been able to deal with the differences between aspirin users and non-users."
"Therefore, these new findings by Chan et al cannot overcome the accumulated evidence that aspirin is not particularly effective for the primary prevention of death from cardiovascular disease in women," he concludes.
Women who take low to moderate doses of aspirin have a reduced risk of death from any cause, and especially heart disease–related deaths, according to a report in the March 26 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Some studies have provided evidence that aspirin may reduce the risk of heart disease and some types of cancer, the two leading causes of death in U.S. women, according to background information in the article. However, it is unclear whether aspirin reduces the risk of death overall for women.
Andrew T. Chan, M.D., M.P.H., Massachusetts General Hospital and Harvard Medical School, Boston, and colleagues examined the association between aspirin use and death in 79,439 women enrolled in the Nurses’ Health Study, a large group of female nurses who have been followed since 1976. Beginning in 1980 and again every two years through 2004, the women were asked if they used aspirin regularly and if so, how many tablets they typically took per week. At the beginning of the study, the women had no history of cardiovascular disease or cancer.
A total of 45,305 women did not use aspirin; 29,132 took low to moderate doses (one to 14 standard 325-milligram tablets of aspirin per week); and 5,002 took more than 14 tablets per week. By June 1, 2004, 9,477 of the women had died, 1,991 of heart disease and 4,469 of cancer. Women who reported using aspirin currently had a 25 percent lower risk of death from any cause than women who never used aspirin regularly. The association was stronger for death from cardiovascular disease (women who used aspirin had a 38 percent lower risk) than for death from cancer (women who used aspirin had a 12 percent lower risk).
"Use of aspirin for one to five years was associated with significant reductions in cardiovascular mortality," the authors write. "In contrast, a significant reduction in risk of cancer deaths was not observed until after 10 years of aspirin use. The benefit associated with aspirin was confined to low and moderate doses and was significantly greater in older participants and those with more cardiac risk factors."
There are several mechanisms by which aspirin could reduce the risk of death, the authors note. "Aspirin therapy may influence cardiovascular disease and cancer through its effect on common pathogenic pathways such as inflammation, insulin resistance, oxidative stress [damage to the cells caused by oxygen exposure] and cyclooxygenase (COX) enzyme activity," also linked to inflammation, they write.
Because the study looked at women who made the decision themselves whether or not to take aspirin, as opposed to a clinical trial where women are randomly assigned to aspirin or a placebo, the results do not suggest that all women should take aspirin. "Nevertheless, these data support a need for continued investigation of the use of aspirin for chronic disease prevention," the authors conclude.
These findings differ from the results of other studies regarding the benefits of aspirin use in healthy women, leaving confusion about aspirin’s role, writes John A. Baron, M.D., Dartmouth Medical School, Lebanon, N.H., in an accompanying editorial.
Dr. Baron points out that in the Women’s Health Study, researchers followed almost 40,000 women for 11 years and did not find any reduced risk of cardiovascular or other death associated with aspirin therapy, in contrast to the dramatic risk reduction seen in the Nurses’ Health Study. "Is aspirin really that good or is there some other explanation for the findings that differ so much from those of the WHS and other primary prevention trials?" he writes.
"The difference between the NHS and the aggregated data from the WHS and other trials is too large to be explained by potential weaknesses in the randomized studies," Dr. Baron writes. "At the same time, one has to consider that the observational NHS may not have been able to deal with the differences between aspirin users and non-users."
"Therefore, these new findings by Chan et al cannot overcome the accumulated evidence that aspirin is not particularly effective for the primary prevention of death from cardiovascular disease in women," he concludes.
Monday, March 19, 2007
Chest compressions without mouth-to-mouth better
A study published March 17, 2007 in The Lancet, one of the world’s foremost medical journals, finds that the chances of surviving a cardiac arrest outside a hospital setting are almost twice as high if bystanders perform chest-compression-only resuscitation instead of traditional cardiopulmonary resuscitation (CPR) with mouth-to-mouth breathing.
The study analyzed the outcomes of resuscitation attempts performed by laypeople at the scene after they witnessed a person collapse due to cardiac arrest.
"The report confirms that what we have learned in animal experiments applies to humans as well," says Gordon A. Ewy, MD, director of the Sarver Heart Center at The University of Arizona in Tucson where chest-compression-only resuscitation was developed. "Bystander-initiated continuous chest compressions without mouth-to-mouth breathing are the preferable approach for witnessed unexpected collapse, which is usually due to cardiac arrest."
In an invited editorial titled "Cardiac Arrest – Guideline Changes Urgently Needed," published in the same issue of the journal, Ewy notes that eliminating the need for mouth-to-mouth ventilation not only is more effective, but also should dramatically increase the incidence of bystander-initiated resuscitation efforts.
Ewy and the Resuscitation Research Group at the UA Sarver Heart Center have advocated continuous chest compressions without assisted breathing as the appropriate method for cardiac arrest for years.
The study reported in The Lancet analyzed the outcomes of 4,068 cases of witnessed collapse of adults in the Kanto area in Japan. The prospective, multi-center observational study, named SOS-KANTO, is the first large-scale account comparing the survival rates of out-of-hospital cardiac arrest patients who were treated either with or without mouth-to-mouth ventilations by bystanders at the scene.
"For cardiac arrest, the term ‘rescue breathing’ is actually a paradox," says Ewy. "We now know that not only is it not helpful, but it’s often harmful."
Studies showed that because current CPR guidelines call for mouth-to-mouth ventilations, the majority of people would not perform CPR on a stranger, partly out of fear of contracting diseases. Research by UA Sarver Heart Center member Karl B. Kern, MD, and others found that even if bystanders are willing to perform mouth-to-mouth ventilation, it takes too much time away from chest compressions, which have to be continuous to improve the chance of survival.
"We have found that the survival rate is higher even when the blood has less oxygen content, but is moved through the body by continuous chest compressions, than when the blood contains a lot of oxygen but is not circulated well because chest compressions are interrupted for mouth-to-mouth ventilations," Ewy says.
All studies on out-of-hospital cardiac arrest have shown that the chance of survival is greatest in patients whose heart is in a condition that allows paramedics to shock it back into a normal rhythm with a defibrillator. Among these patients, the SOS-KANTO researchers found the percentage surviving with a favorable neurological outcome to be 19.4 percent if bystanders administered chest compressions without mouth-to-mouth ventilations. In contrast, the favorable neurological survival rate in those who received chest compressions and mouth-to-mouth breathing was only 11.2 percent.
While the study provides unequivocal evidence that chest-compression-only resuscitation boosts survival rates for out-of-hospital cardiac arrest, Ewy points out that, for respiratory arrest such as near-drowning, drug overdose or choking, guideline CPR consisting of 2 breaths after every 30 chest compressions is still the appropriate method.
"This study confirms how critically dependent the outcome of out-of-hospital cardiac arrest is on the willingness of bystanders to activate emergency medical services and promptly initiate continuous chest compressions in a case of witnessed unexpected collapse in an adult," Ewy says.
"It is also very interesting to find how a sizeable group of laypeople, by spontaneously performing a technique that has neither been taught nor formally endorsed, achieved better outcomes than with a technique that has been advocated and taught at a cost of millions of dollars and millions of man-hours."
The study analyzed the outcomes of resuscitation attempts performed by laypeople at the scene after they witnessed a person collapse due to cardiac arrest.
"The report confirms that what we have learned in animal experiments applies to humans as well," says Gordon A. Ewy, MD, director of the Sarver Heart Center at The University of Arizona in Tucson where chest-compression-only resuscitation was developed. "Bystander-initiated continuous chest compressions without mouth-to-mouth breathing are the preferable approach for witnessed unexpected collapse, which is usually due to cardiac arrest."
In an invited editorial titled "Cardiac Arrest – Guideline Changes Urgently Needed," published in the same issue of the journal, Ewy notes that eliminating the need for mouth-to-mouth ventilation not only is more effective, but also should dramatically increase the incidence of bystander-initiated resuscitation efforts.
Ewy and the Resuscitation Research Group at the UA Sarver Heart Center have advocated continuous chest compressions without assisted breathing as the appropriate method for cardiac arrest for years.
The study reported in The Lancet analyzed the outcomes of 4,068 cases of witnessed collapse of adults in the Kanto area in Japan. The prospective, multi-center observational study, named SOS-KANTO, is the first large-scale account comparing the survival rates of out-of-hospital cardiac arrest patients who were treated either with or without mouth-to-mouth ventilations by bystanders at the scene.
"For cardiac arrest, the term ‘rescue breathing’ is actually a paradox," says Ewy. "We now know that not only is it not helpful, but it’s often harmful."
Studies showed that because current CPR guidelines call for mouth-to-mouth ventilations, the majority of people would not perform CPR on a stranger, partly out of fear of contracting diseases. Research by UA Sarver Heart Center member Karl B. Kern, MD, and others found that even if bystanders are willing to perform mouth-to-mouth ventilation, it takes too much time away from chest compressions, which have to be continuous to improve the chance of survival.
"We have found that the survival rate is higher even when the blood has less oxygen content, but is moved through the body by continuous chest compressions, than when the blood contains a lot of oxygen but is not circulated well because chest compressions are interrupted for mouth-to-mouth ventilations," Ewy says.
All studies on out-of-hospital cardiac arrest have shown that the chance of survival is greatest in patients whose heart is in a condition that allows paramedics to shock it back into a normal rhythm with a defibrillator. Among these patients, the SOS-KANTO researchers found the percentage surviving with a favorable neurological outcome to be 19.4 percent if bystanders administered chest compressions without mouth-to-mouth ventilations. In contrast, the favorable neurological survival rate in those who received chest compressions and mouth-to-mouth breathing was only 11.2 percent.
While the study provides unequivocal evidence that chest-compression-only resuscitation boosts survival rates for out-of-hospital cardiac arrest, Ewy points out that, for respiratory arrest such as near-drowning, drug overdose or choking, guideline CPR consisting of 2 breaths after every 30 chest compressions is still the appropriate method.
"This study confirms how critically dependent the outcome of out-of-hospital cardiac arrest is on the willingness of bystanders to activate emergency medical services and promptly initiate continuous chest compressions in a case of witnessed unexpected collapse in an adult," Ewy says.
"It is also very interesting to find how a sizeable group of laypeople, by spontaneously performing a technique that has neither been taught nor formally endorsed, achieved better outcomes than with a technique that has been advocated and taught at a cost of millions of dollars and millions of man-hours."
"Manly Men' Bounce Back Better From Injury
Traditional Masculinity Can Aid Recovery from Serious Injuries, MU Study Finds
For years, experts have said that the strong, silent male is not one to ask for help when he's hurt, and therefore at a disadvantage when it comes to getting better. But new research says this might not be completely accurate. This masculine identity often associated with men in the armed forces and other high-risk occupations may actually encourage and quicken a man's recovery from serious injuries, says a new exploratory study from the University of Missouri-Columbia. The study is the first to quantitatively confirm correlations between masculinity and men's recovery.
The study assessed men's conformity to masculine roles and included a longitudinal component in which their level of improvement in functioning was assessed. It found that men with higher masculinity conformity levels were observed to display greater improvement from initial hospitalization to one year after leaving the hospital.
Though more research is needed, Glenn Good, associate professor of educational, school and counseling psychology in MU College of Education, said the study provides some unexpected findings. Previous studies have generally found that more traditional views of masculinity are barriers toward health and recovery, in that it encourages dangerous activities and discourages men from seeking help with their problems or accepting vulnerability.
"It has long been assumed that men are not as concerned and don't take as good of care of their health," Good said, "but what we're seeing here is that the same ideas that led to their injuries may actually encourage their recovery."
The tenets of traditional masculinity have been said to include the ability to withstand hardship, 'stick-to-it-iveness' and the willingness to see something through to the end, according to the study.
"The immediate message here is to encourage psychotherapy along with traditional methods of healing," Good said. "Most people with serious injuries are provided primarily biomedical treatments, but it is important to look at psycho-social issues that affect their recovery as well. In terms of a social response, this study encourages us to redefine strength and masculinity in ways that benefit every stage of health care."
For years, experts have said that the strong, silent male is not one to ask for help when he's hurt, and therefore at a disadvantage when it comes to getting better. But new research says this might not be completely accurate. This masculine identity often associated with men in the armed forces and other high-risk occupations may actually encourage and quicken a man's recovery from serious injuries, says a new exploratory study from the University of Missouri-Columbia. The study is the first to quantitatively confirm correlations between masculinity and men's recovery.
The study assessed men's conformity to masculine roles and included a longitudinal component in which their level of improvement in functioning was assessed. It found that men with higher masculinity conformity levels were observed to display greater improvement from initial hospitalization to one year after leaving the hospital.
Though more research is needed, Glenn Good, associate professor of educational, school and counseling psychology in MU College of Education, said the study provides some unexpected findings. Previous studies have generally found that more traditional views of masculinity are barriers toward health and recovery, in that it encourages dangerous activities and discourages men from seeking help with their problems or accepting vulnerability.
"It has long been assumed that men are not as concerned and don't take as good of care of their health," Good said, "but what we're seeing here is that the same ideas that led to their injuries may actually encourage their recovery."
The tenets of traditional masculinity have been said to include the ability to withstand hardship, 'stick-to-it-iveness' and the willingness to see something through to the end, according to the study.
"The immediate message here is to encourage psychotherapy along with traditional methods of healing," Good said. "Most people with serious injuries are provided primarily biomedical treatments, but it is important to look at psycho-social issues that affect their recovery as well. In terms of a social response, this study encourages us to redefine strength and masculinity in ways that benefit every stage of health care."
Apple consumers reap heart-health benefits
Apple consumers reap heart-health benefits thanks to flavonoid content, says new research
American Heart Association new recommendations support increased fruit, vegetable consumption
Apples may prove to be a winner when it comes to reducing the risk of heart disease, says a new study of more than 34,000 women. In this study, flavonoid-rich apples were found to be one of three foods (along with red wine and pears) that decrease the risk of mortality for both coronary heart disease (CHD) and cardiovascular disease (CVD) among post-menopausal women, The findings were published in the March 2007 American Journal of Clinical Nutrition.
Women of all ages are encouraged to consume more fruit and vegetables, including apples and apple products, for heart health. However, this study focused on postmenopausal woman, a group becoming more aware of the risk for heart disease. Using a government database that assesses the flavonoid-compound content of foods, the researchers hypothesized that flavonoid intake (in general and from specific foods), might be inversely associated with mortality from CVD and CHD among the women in the study groupSubjects selected for this research analysis were postmenopausal and part of the ongoing Iowa Women's Health Study, each of which has been monitored for dietary intake and various health outcomes for nearly 20 years.
As a result of the extensive analysis that considered what the women ate, the types of cardiovascular-related diseases they experienced, and the overall flavonoid content of an extensive list of foods, the researchers concluded that consumption of apples, pears and red wine were linked with the lowest risk for mortality related to both CHD and CVD (not just one or the other).
"Flavonoids are compounds found in small quantities in numerous plant foods, including fruits and vegetables, tea, wine, nuts and seeds, and herbs and spices," say the university researchers from the University of Minnesota and the University of Oslo (Norway) Earlier research has indicated that flavonoids also have antioxidant properties that are linked to the reduction of oxidation of the bad (LDL - low density lipoprotein) cholesterol which have been linked in various ways with the development of CVD. According to the government database cited in this paper, apples contain a wide variety of flavonoid compounds.
The researchers also believe this is the first prospective study of postmenopausal women to report on the intake and impact of total and specific flavonoid subclasses. They conclude, "Dietary intakes of flavanones, anthocyanins, and certain foods rich in flavonoids were associated with reduced risk of death due to CHD, CVD and all causes."
The publication of this positive study for apples comes on the heels of updated heart disease prevention guidelines for women just released by the American Heart Association in the February 20 issue of Circulation. As part of their guidelines, AHA emphasizes that women increase their intake of fruits and vegetables to help prevent heart disease over their lifetime, not just to reduce short-term risk. Worldwide, cardiovascular disease is the largest single cause of mortality among women, accounting for one third of all deaths.
American Heart Association new recommendations support increased fruit, vegetable consumption
Apples may prove to be a winner when it comes to reducing the risk of heart disease, says a new study of more than 34,000 women. In this study, flavonoid-rich apples were found to be one of three foods (along with red wine and pears) that decrease the risk of mortality for both coronary heart disease (CHD) and cardiovascular disease (CVD) among post-menopausal women, The findings were published in the March 2007 American Journal of Clinical Nutrition.
Women of all ages are encouraged to consume more fruit and vegetables, including apples and apple products, for heart health. However, this study focused on postmenopausal woman, a group becoming more aware of the risk for heart disease. Using a government database that assesses the flavonoid-compound content of foods, the researchers hypothesized that flavonoid intake (in general and from specific foods), might be inversely associated with mortality from CVD and CHD among the women in the study groupSubjects selected for this research analysis were postmenopausal and part of the ongoing Iowa Women's Health Study, each of which has been monitored for dietary intake and various health outcomes for nearly 20 years.
As a result of the extensive analysis that considered what the women ate, the types of cardiovascular-related diseases they experienced, and the overall flavonoid content of an extensive list of foods, the researchers concluded that consumption of apples, pears and red wine were linked with the lowest risk for mortality related to both CHD and CVD (not just one or the other).
"Flavonoids are compounds found in small quantities in numerous plant foods, including fruits and vegetables, tea, wine, nuts and seeds, and herbs and spices," say the university researchers from the University of Minnesota and the University of Oslo (Norway) Earlier research has indicated that flavonoids also have antioxidant properties that are linked to the reduction of oxidation of the bad (LDL - low density lipoprotein) cholesterol which have been linked in various ways with the development of CVD. According to the government database cited in this paper, apples contain a wide variety of flavonoid compounds.
The researchers also believe this is the first prospective study of postmenopausal women to report on the intake and impact of total and specific flavonoid subclasses. They conclude, "Dietary intakes of flavanones, anthocyanins, and certain foods rich in flavonoids were associated with reduced risk of death due to CHD, CVD and all causes."
The publication of this positive study for apples comes on the heels of updated heart disease prevention guidelines for women just released by the American Heart Association in the February 20 issue of Circulation. As part of their guidelines, AHA emphasizes that women increase their intake of fruits and vegetables to help prevent heart disease over their lifetime, not just to reduce short-term risk. Worldwide, cardiovascular disease is the largest single cause of mortality among women, accounting for one third of all deaths.
Soy found protective against localized prostate cancer
Soy found protective against localized prostate cancer
Large-scale japanese study indicates no protection against advanced prostate cancer
The largest study examining the relationship between the traditional soy-rich Japanese diet and development of prostate cancer in Japanese men has come to a seemingly contradictory conclusion: intake of isoflavone chemicals, derived largely from soy foods, decreased the risk of localized prostate cancer but increased the risk of advanced prostate cancer.
The prospective study of 43,509 men, published in the March issue of Cancer Epidemiology, Biomarkers & Prevention, suggests that the effects of isoflavones on prostate cancer development may differ according to disease stage, say researchers at the National Cancer Center in Japan.
One possible explanation is that isoflavones may delay the progression of latent prostate cancer only; once tumors lose estrogen-receptor beta expression and become aggressive, isoflavones may fail to protect against the development of advanced cancer, and might even increase the risk of progression, possibly by reducing serum testosterone, researchers say. It is also possible that advanced and localized prostate cancer may be different tumor subtypes, which may react differently to isoflavones.
"The present findings provide no clear understanding of when or how localized cancer will develop to aggressive cancer, and of the related effect of isoflavones," said the study's first author, Norie Kurahashi, M.D., of the Epidemiology and Prevention Division of the National Cancer Center.
"Given that Japanese consume isoflavones regularly throughout life, we do not know the period during which the effects of isoflavones on prostate cancer are preventive, and further research is required to find that out, including well-designed clinical trials," she said.
Until those studies are done, the researchers recommend that Japanese men continue to consume isoflavones through their food and not through supplements.
"Consumption of isoflavones from traditional Japanese food throughout life may protect against the incidence of prostate cancer, but we cannot recommend the use of isoflavones from supplements for people who do not regularly consume these chemicals, because the relationship between isoflavones and the risk of advanced prostate cancer is not yet clear," Kurahashi said.
Isoflavones act as both strong antioxidants and plant-based estrogens. Soybeans are the most common source of isoflavones, especially genistein and daidzein, which have been shown in some animal studies to exert a protective effect against prostate cancer.
Japanese men eat significantly more soy-based foods than do Western men, and the incidence of prostate cancer is much lower in Asian countries than in Western countries. Still, reviews of latent, or clinically insignificant, prostate cancer findings in autopsy reports have revealed no difference between the populations so scientists have theorized that isoflavones stop latent cancers from developing further.
But because smaller epidemiological studies in Japan have reached differing conclusions about the protective effects of soy on prostate cancer development, this research team conducted the most comprehensive analysis to date. They polled thousands of men age 40-69 about their consumption of 147 foods, the most popular of which were miso soup (primarily made from fermented soybeans), natto (also a product of fermented soybeans) and tofu, made from soy milk. Japanese consume miso soup more frequently, usually daily, than other soy foods, and miso, natto, and tofu account for about 90 percent of the population's consumption of daidzein and genistein, according to Kurahashi.
The researchers then followed participants from 1995 through 2004 and found that 307 men were diagnosed with prostate cancer. In this group, 74 cases were advanced, 218 were confined to the prostate organ, and 15 were of undetermined stage.
They concluded that intake of genistein, daidzein, miso soup and soy food had no overall link to diagnosis of prostate cancer. However, they calculated that the risk of developing localized prostate cancer was 50 percent lower in men who ate the most isoflavones compared to men who ate the least − meaning that men in the top category ate between two and three times as much isoflavone-rich food.
However, in a discovery they cannot explain, they also calculated that the risk of developing advanced prostate cancer was twice as high in men who consumed two or more bowls of miso soup a day than in men who ate less than one bowl of soup.
They also found that the protective effect of isoflavone-rich food was strongest in men who were older than 60: the more isoflavones they ate, the more they reduced their risk of developing localized prostate cancer. "Isoflavone may be protective for localized prostate cancer only in men aged more than 60 years, and may not have a protective effect in the early stage of prostate cancer in younger men," the researchers conclude in their study.
The inconsistencies in the finding − that isoflavones decreased the risk of localized prostate cancer, but not the risk of advanced prostate cancer − could be errors in food measurement, or could be due to the fact that the number of participants who developed advanced prostate cancer was small, said Kurahashi. Or, as researchers speculate, isoflavones could interact with the estrogen receptor on prostate tissue enough to inhibit production of testosterone, which can fuel prostate cancer. When tumors lose all of their estrogen receptors and stop responding to isoflavone-induced hormonal interference, they grow aggressively.
"A broad body of research is required to clarify the timing and period of isoflavones' preventive effect on prostate cancer development," Kurahashi said.
Large-scale japanese study indicates no protection against advanced prostate cancer
The largest study examining the relationship between the traditional soy-rich Japanese diet and development of prostate cancer in Japanese men has come to a seemingly contradictory conclusion: intake of isoflavone chemicals, derived largely from soy foods, decreased the risk of localized prostate cancer but increased the risk of advanced prostate cancer.
The prospective study of 43,509 men, published in the March issue of Cancer Epidemiology, Biomarkers & Prevention, suggests that the effects of isoflavones on prostate cancer development may differ according to disease stage, say researchers at the National Cancer Center in Japan.
One possible explanation is that isoflavones may delay the progression of latent prostate cancer only; once tumors lose estrogen-receptor beta expression and become aggressive, isoflavones may fail to protect against the development of advanced cancer, and might even increase the risk of progression, possibly by reducing serum testosterone, researchers say. It is also possible that advanced and localized prostate cancer may be different tumor subtypes, which may react differently to isoflavones.
"The present findings provide no clear understanding of when or how localized cancer will develop to aggressive cancer, and of the related effect of isoflavones," said the study's first author, Norie Kurahashi, M.D., of the Epidemiology and Prevention Division of the National Cancer Center.
"Given that Japanese consume isoflavones regularly throughout life, we do not know the period during which the effects of isoflavones on prostate cancer are preventive, and further research is required to find that out, including well-designed clinical trials," she said.
Until those studies are done, the researchers recommend that Japanese men continue to consume isoflavones through their food and not through supplements.
"Consumption of isoflavones from traditional Japanese food throughout life may protect against the incidence of prostate cancer, but we cannot recommend the use of isoflavones from supplements for people who do not regularly consume these chemicals, because the relationship between isoflavones and the risk of advanced prostate cancer is not yet clear," Kurahashi said.
Isoflavones act as both strong antioxidants and plant-based estrogens. Soybeans are the most common source of isoflavones, especially genistein and daidzein, which have been shown in some animal studies to exert a protective effect against prostate cancer.
Japanese men eat significantly more soy-based foods than do Western men, and the incidence of prostate cancer is much lower in Asian countries than in Western countries. Still, reviews of latent, or clinically insignificant, prostate cancer findings in autopsy reports have revealed no difference between the populations so scientists have theorized that isoflavones stop latent cancers from developing further.
But because smaller epidemiological studies in Japan have reached differing conclusions about the protective effects of soy on prostate cancer development, this research team conducted the most comprehensive analysis to date. They polled thousands of men age 40-69 about their consumption of 147 foods, the most popular of which were miso soup (primarily made from fermented soybeans), natto (also a product of fermented soybeans) and tofu, made from soy milk. Japanese consume miso soup more frequently, usually daily, than other soy foods, and miso, natto, and tofu account for about 90 percent of the population's consumption of daidzein and genistein, according to Kurahashi.
The researchers then followed participants from 1995 through 2004 and found that 307 men were diagnosed with prostate cancer. In this group, 74 cases were advanced, 218 were confined to the prostate organ, and 15 were of undetermined stage.
They concluded that intake of genistein, daidzein, miso soup and soy food had no overall link to diagnosis of prostate cancer. However, they calculated that the risk of developing localized prostate cancer was 50 percent lower in men who ate the most isoflavones compared to men who ate the least − meaning that men in the top category ate between two and three times as much isoflavone-rich food.
However, in a discovery they cannot explain, they also calculated that the risk of developing advanced prostate cancer was twice as high in men who consumed two or more bowls of miso soup a day than in men who ate less than one bowl of soup.
They also found that the protective effect of isoflavone-rich food was strongest in men who were older than 60: the more isoflavones they ate, the more they reduced their risk of developing localized prostate cancer. "Isoflavone may be protective for localized prostate cancer only in men aged more than 60 years, and may not have a protective effect in the early stage of prostate cancer in younger men," the researchers conclude in their study.
The inconsistencies in the finding − that isoflavones decreased the risk of localized prostate cancer, but not the risk of advanced prostate cancer − could be errors in food measurement, or could be due to the fact that the number of participants who developed advanced prostate cancer was small, said Kurahashi. Or, as researchers speculate, isoflavones could interact with the estrogen receptor on prostate tissue enough to inhibit production of testosterone, which can fuel prostate cancer. When tumors lose all of their estrogen receptors and stop responding to isoflavone-induced hormonal interference, they grow aggressively.
"A broad body of research is required to clarify the timing and period of isoflavones' preventive effect on prostate cancer development," Kurahashi said.
Friday, March 16, 2007
Is Too Much Exercise a Bad Thing?
University of Maryland Researchers Find Heart Disease in a Marathon Runner:
Doctors at the University of Maryland Medical Center had a mystery on their hands. A 51-year-old physician colleague who looked the picture of health - no cardiovascular risks, a marathon runner who had exercised vigorously each day for 30 years - had just flunked a calcium screening scan of his heart.
The patient had expected a score indicating a healthy cardiovascular system. Instead, the images indicated a high score: a build-up of calcium in his coronary arteries put him at high risk for blocked blood vessels and a possible heart attack.
The mystery was all the more intriguing because his resting blood pressure and fasting cholesterol levels, the usual measures of cardiovascular health, were in the normal range.
In the March 1, 2007, issue of the American Journal of Cardiology, the researchers say this is the first case, to their knowledge, of advanced coronary calcification in an otherwise healthy middle-aged male marathon runner who lacked traditional cardiac risk factors and had no symptoms of heart disease.
The researchers conclude that the physician's intense, long-term exercise regime, coupled with a predisposition toward a type of hypertension, contributed to his cardiovascular disease. "In this particular individual, we think that oxidative stress was an important contributor," says the study's senior author, Michael Miller, M.D., director of preventive cardiology at the University of Maryland Medical Center and associate professor of medicine at the University of Maryland School of Medicine. "But we also found that this individual has exercise-induced hypertension, which I think is vastly under-diagnosed."
Oxidative stress is a byproduct of the normal cellular metabolism of oxygen. It refers to cell, tissue or organ damage from a class of molecules associated with oxygen metabolism, including unstable molecules called "free radicals." Oxidative stress plays a role in many heart, lung, blood and sleep disorders, including atherosclerosis, or hardening of the arteries, hypertension, heart failure, asthma and sleep apnea.
To help gage the impact of oxidative stress on the patient's cardiovascular system, his doctors evaluated the response to exercise of the endothelium, the lining of his arteries. An ultrasound device was used to measure what is known as flow-mediated vasodilation. It shows how well the endothelium responds to a sudden increase in the flow of blood through an artery in the upper arm. The endothelium in a healthy vessel typically dilates or expands during this test to accommodate the increased blood flow, while an impaired vessel constricts or narrows.
The patient's blood vessel dilation was normal before exercising. But after exercise, vessel constriction occurred immediately and showed no improvement after an hour. To put this response into perspective, the researchers administered the same exercise/blood vessel response test to a group of ten men whose mean age was 41. The vessels of these men initially constricted, but improved significantly one hour after exercise.
Several weeks later, the patient was given vitamins C and E just before exercise and was tested again for endothelial response. These vitamins are known as antioxidants and may protect cells from free radical damage. This time, the test revealed a partial reversal of the blood vessel constriction after one hour, and normalization after two hours.
"As he took the vitamin C and vitamin E, you could see improvements in his brachial arteries," says Dr. Miller. "We recommended that the patient take these vitamins before he runs."
With half the mystery solved, the research team explored another possible cause of the calcium buildup - elevated blood pressure. Hypertension can cause artery walls to thicken and the endothelium to narrow. This narrowing can promote the formation of fatty plaque deposits in artery walls. The plaque, from cholesterol and fats, can eventually harden or calcify.
Although hypertension did not seem to be a risk factor for this patient, exercise is a major factor in his life. So, the researchers turned to a treadmill stress test to measure his blood pressure during exercise. At the start of the treadmill test, his baseline blood pressure was normal, 118/78 millimeters of mercury (mmHg). He was in such great shape that it took 20 minutes to reach high blood pressure levels, and this happened only after the treadmill speed and incline had been raised. But by the end of the test, his blood pressure had soared to 230/78 mmHg. A check of several of his previous treadmill tests indicated a similar rise in blood pressure.
On the basis of running duration and intensity, the researchers estimated that the patient spent about 30 minutes a day at a systolic blood pressure above 200 mmHg. This number is well into the blood pressure danger zone and meets one definition of exercise-induced hypertension - a jump of at least 60 mmHg from baseline after exercise.
This finding should be investigated further, says co-investigator Matthew R. Weir, M.D., head of nephrology at the University of Maryland Medical Center and professor of medicine and head of the division of nephrology at the University of Maryland School of Medicine. "Because we know that blood pressure rises during a stress test, we tend not to pay attention to it. We're more interested in changes in electrical activity and the redistribution of blood during exercise, which could indicate inadequate blood supply to the heart muscle," says Dr. Weir. "The question is, should we pay more attention to treadmill-induced changes in blood pressure as a means to identify people at risk for developing coronary artery disease?"
Dr. Miller adds another question: "Should we screen all middle-aged individuals who want to participate in an exercise program to make sure they don't have exercise-induced high blood pressure?"
Unlike cholesterol or triglyceride levels, blood pressure levels fluctuate dramatically throughout the day, depending on a variety of factors such as exercise, emotions and even the time of day. In light of that phenomenon, Dr. Weir says the study raises another issue. "This research indicates that we need a more dynamic measure of blood pressure to truly profile the risk of an individual. We've been using casual, at-rest office readings of blood pressure for more than 50 years. It's not bad, but it's not the answer." The treadmill is one way to gather a more dynamic measurement, but he says there's an easier option. "It can even be done at home if you have a blood pressure cuff and someone who can take your blood pressure at peak exercise."
The patient in the study continues to run, but is now taking medications to lower both his cholesterol and blood pressure. Despite his exercise regime, he appears to be in the same boat as millions of Americans who do not exercise regularly. So, is too much exercise a bad thing? The physicians answer to the contrary. "We are not publishing this report to suggest in any way that people should not be exercising. Exercise has stood the test of time as being one of the best ways to modify cardiovascular risk," says Dr. Miller. "But what we're looking at are improved detection methods for predicting those at risk. Exercise-induced high blood pressure may be a part of that."
Doctors at the University of Maryland Medical Center had a mystery on their hands. A 51-year-old physician colleague who looked the picture of health - no cardiovascular risks, a marathon runner who had exercised vigorously each day for 30 years - had just flunked a calcium screening scan of his heart.
The patient had expected a score indicating a healthy cardiovascular system. Instead, the images indicated a high score: a build-up of calcium in his coronary arteries put him at high risk for blocked blood vessels and a possible heart attack.
The mystery was all the more intriguing because his resting blood pressure and fasting cholesterol levels, the usual measures of cardiovascular health, were in the normal range.
In the March 1, 2007, issue of the American Journal of Cardiology, the researchers say this is the first case, to their knowledge, of advanced coronary calcification in an otherwise healthy middle-aged male marathon runner who lacked traditional cardiac risk factors and had no symptoms of heart disease.
The researchers conclude that the physician's intense, long-term exercise regime, coupled with a predisposition toward a type of hypertension, contributed to his cardiovascular disease. "In this particular individual, we think that oxidative stress was an important contributor," says the study's senior author, Michael Miller, M.D., director of preventive cardiology at the University of Maryland Medical Center and associate professor of medicine at the University of Maryland School of Medicine. "But we also found that this individual has exercise-induced hypertension, which I think is vastly under-diagnosed."
Oxidative stress is a byproduct of the normal cellular metabolism of oxygen. It refers to cell, tissue or organ damage from a class of molecules associated with oxygen metabolism, including unstable molecules called "free radicals." Oxidative stress plays a role in many heart, lung, blood and sleep disorders, including atherosclerosis, or hardening of the arteries, hypertension, heart failure, asthma and sleep apnea.
To help gage the impact of oxidative stress on the patient's cardiovascular system, his doctors evaluated the response to exercise of the endothelium, the lining of his arteries. An ultrasound device was used to measure what is known as flow-mediated vasodilation. It shows how well the endothelium responds to a sudden increase in the flow of blood through an artery in the upper arm. The endothelium in a healthy vessel typically dilates or expands during this test to accommodate the increased blood flow, while an impaired vessel constricts or narrows.
The patient's blood vessel dilation was normal before exercising. But after exercise, vessel constriction occurred immediately and showed no improvement after an hour. To put this response into perspective, the researchers administered the same exercise/blood vessel response test to a group of ten men whose mean age was 41. The vessels of these men initially constricted, but improved significantly one hour after exercise.
Several weeks later, the patient was given vitamins C and E just before exercise and was tested again for endothelial response. These vitamins are known as antioxidants and may protect cells from free radical damage. This time, the test revealed a partial reversal of the blood vessel constriction after one hour, and normalization after two hours.
"As he took the vitamin C and vitamin E, you could see improvements in his brachial arteries," says Dr. Miller. "We recommended that the patient take these vitamins before he runs."
With half the mystery solved, the research team explored another possible cause of the calcium buildup - elevated blood pressure. Hypertension can cause artery walls to thicken and the endothelium to narrow. This narrowing can promote the formation of fatty plaque deposits in artery walls. The plaque, from cholesterol and fats, can eventually harden or calcify.
Although hypertension did not seem to be a risk factor for this patient, exercise is a major factor in his life. So, the researchers turned to a treadmill stress test to measure his blood pressure during exercise. At the start of the treadmill test, his baseline blood pressure was normal, 118/78 millimeters of mercury (mmHg). He was in such great shape that it took 20 minutes to reach high blood pressure levels, and this happened only after the treadmill speed and incline had been raised. But by the end of the test, his blood pressure had soared to 230/78 mmHg. A check of several of his previous treadmill tests indicated a similar rise in blood pressure.
On the basis of running duration and intensity, the researchers estimated that the patient spent about 30 minutes a day at a systolic blood pressure above 200 mmHg. This number is well into the blood pressure danger zone and meets one definition of exercise-induced hypertension - a jump of at least 60 mmHg from baseline after exercise.
This finding should be investigated further, says co-investigator Matthew R. Weir, M.D., head of nephrology at the University of Maryland Medical Center and professor of medicine and head of the division of nephrology at the University of Maryland School of Medicine. "Because we know that blood pressure rises during a stress test, we tend not to pay attention to it. We're more interested in changes in electrical activity and the redistribution of blood during exercise, which could indicate inadequate blood supply to the heart muscle," says Dr. Weir. "The question is, should we pay more attention to treadmill-induced changes in blood pressure as a means to identify people at risk for developing coronary artery disease?"
Dr. Miller adds another question: "Should we screen all middle-aged individuals who want to participate in an exercise program to make sure they don't have exercise-induced high blood pressure?"
Unlike cholesterol or triglyceride levels, blood pressure levels fluctuate dramatically throughout the day, depending on a variety of factors such as exercise, emotions and even the time of day. In light of that phenomenon, Dr. Weir says the study raises another issue. "This research indicates that we need a more dynamic measure of blood pressure to truly profile the risk of an individual. We've been using casual, at-rest office readings of blood pressure for more than 50 years. It's not bad, but it's not the answer." The treadmill is one way to gather a more dynamic measurement, but he says there's an easier option. "It can even be done at home if you have a blood pressure cuff and someone who can take your blood pressure at peak exercise."
The patient in the study continues to run, but is now taking medications to lower both his cholesterol and blood pressure. Despite his exercise regime, he appears to be in the same boat as millions of Americans who do not exercise regularly. So, is too much exercise a bad thing? The physicians answer to the contrary. "We are not publishing this report to suggest in any way that people should not be exercising. Exercise has stood the test of time as being one of the best ways to modify cardiovascular risk," says Dr. Miller. "But what we're looking at are improved detection methods for predicting those at risk. Exercise-induced high blood pressure may be a part of that."
Tuesday, March 13, 2007
Cocoa Health Benefits Could Outshine Penicillin
The health benefits of epicatechin, a compound found in cocoa, are so striking that it may rival penicillin and anaesthesia in terms of importance to public health, reports Marina Murphy in Chemistry & Industry, the magazine of the SCI. Norman Hollenberg, professor of medicine at Harvard Medical School, told C&I that epicatechin is so important that it should be considered a vitamin.
Hollenberg has spent years studying the benefits of cocoa drinking on the Kuna people in Panama. He found that the risk of 4 of the 5 most common killer diseases: stroke, heart failure, cancer and diabetes, is reduced to less then 10% in the Kuna. They can drink up to 40 cups of cocoa a week. Natural cocoa has high levels of epicatechin.
'If these observations predict the future, then we can say without blushing that they are among the most important observations in the history of medicine,' Hollenberg says. ‘We all agree that penicillin and anaesthesia are enormously important. But epicatechin could potentially get rid of 4 of the 5 most common diseases in the western world, how important does that make epicatechin?... I would say very important’
Nutrition expert Daniel Fabricant says that Hollenberg’s results, although observational, are so impressive that they may even warrant a rethink of how vitamins are defined. Epicatechin does not currently meet the criteria. Vitamins are defined as essential to the normal functioning, metabolism, regulation and growth of cells and deficiency is usually linked to disease. At the moment, the science does not support epicatechin having an essential role. But, Fabricant, who is vice president scientific affairs at the Natural Products Association, says: 'the link between high epicatechin consumption and a decreased risk of killer disease is so striking, it should be investigated further. It may be that these diseases are the result of epicatechin deficiency,' he says.
Currently, there are only 13 essential vitamins. An increase in the number of vitamins would provide significant opportunity for nutritional companies to expand their range of products. Flavanols like epicatechin are removed for commercial cocoas because they tend to have a bitter taste. So there is huge scope for nutritional companies to develop epicatechin supplements or capsules
Epicatechin is also found in teas, wine, chocolate and some fruit and vegetables.
Chemistry & Industry: http://www.chemind.org
Hollenberg has spent years studying the benefits of cocoa drinking on the Kuna people in Panama. He found that the risk of 4 of the 5 most common killer diseases: stroke, heart failure, cancer and diabetes, is reduced to less then 10% in the Kuna. They can drink up to 40 cups of cocoa a week. Natural cocoa has high levels of epicatechin.
'If these observations predict the future, then we can say without blushing that they are among the most important observations in the history of medicine,' Hollenberg says. ‘We all agree that penicillin and anaesthesia are enormously important. But epicatechin could potentially get rid of 4 of the 5 most common diseases in the western world, how important does that make epicatechin?... I would say very important’
Nutrition expert Daniel Fabricant says that Hollenberg’s results, although observational, are so impressive that they may even warrant a rethink of how vitamins are defined. Epicatechin does not currently meet the criteria. Vitamins are defined as essential to the normal functioning, metabolism, regulation and growth of cells and deficiency is usually linked to disease. At the moment, the science does not support epicatechin having an essential role. But, Fabricant, who is vice president scientific affairs at the Natural Products Association, says: 'the link between high epicatechin consumption and a decreased risk of killer disease is so striking, it should be investigated further. It may be that these diseases are the result of epicatechin deficiency,' he says.
Currently, there are only 13 essential vitamins. An increase in the number of vitamins would provide significant opportunity for nutritional companies to expand their range of products. Flavanols like epicatechin are removed for commercial cocoas because they tend to have a bitter taste. So there is huge scope for nutritional companies to develop epicatechin supplements or capsules
Epicatechin is also found in teas, wine, chocolate and some fruit and vegetables.
Chemistry & Industry: http://www.chemind.org
Women and heart disease
Cardiovascular disease is the leading cause of death among women. Analyses suggest clinically relevant differences between women and men in terms of prevalence, presentation, management and outcomes of the disease, but little is known about why these differences exist. In a supplement to the Mar. 13 issue of CMAJ (available online at www.cmaj.ca/cgi/content/full/176/6/S1), Dr. Louise Pilote and coauthors from across Canada offer a comprehensive review of sex-specific issues related to cardiovascular disease. Eight broad topics are addressed, including the burden of cardiovascular disease in men and women, and cardiovascular risk factors in girls and boys. An in-depth review of the scientific literature is provided on each topic, along with a summary of current knowledge about the topic and questions that have yet to be answered. For instance, why are young women with acute coronary syndrome at greater risk of death than young men are with acute coronary syndrome, and why are the incidence and mortality of cardiovascular disease decreasing among men but stable among women?
Pacifier Use May Lower Risk of SIDS
Pacifier Use Most Beneficial Between Ages of One Month and One Year
The risk of Sudden Infant Death Syndrome (SIDS), the third leading cause of infant death, may be lowered through the use of a pacifier. According to an article in Nursing for Women’s Health, neonatal health care practitioners should counsel new parents on the potential benefits of using a pacifier.
This advice follows the release of updated recommendations from the American Academy of Pediatrics (AAP) Task Force on SIDS, suggesting that pacifier use be encouraged for children less than one year of age. “It’s important to note that the AAP’s pacifier recommendations are not unique,” says author Elizabeth Damato, Ph.D., RN. “A variety of studies have indicated that pacifier use lowers the risk of SIDS, and several other countries have made similar recommendations.” She stresses, however, that parents must be counseled on how to use pacifiers safely.
“Pacifiers shouldn’t be used before the age of one month in breastfed infants to avoid the disruption of regular feeding habits,” says Damato. “Also, infants should not be forced to take a pacifier and parents should not reinsert it once the infant falls asleep.” Parents should also avoid using homemade pacifiers, avoid strings or cords to secure the pacifier to the child, and regularly clean and replace pacifiers.
Even though evidence is mounting that pacifiers help to prevent SIDS, no one knows why. “Because SIDS happens so rarely, it is difficult to do large-scale controlled studies to determine why pacifiers might help,” says Damato. “However, because the risk for serious side effects is greatly reduced if pacifiers are used properly, they are a safe and sensible option in the battle against SIDS.”
The risk of Sudden Infant Death Syndrome (SIDS), the third leading cause of infant death, may be lowered through the use of a pacifier. According to an article in Nursing for Women’s Health, neonatal health care practitioners should counsel new parents on the potential benefits of using a pacifier.
This advice follows the release of updated recommendations from the American Academy of Pediatrics (AAP) Task Force on SIDS, suggesting that pacifier use be encouraged for children less than one year of age. “It’s important to note that the AAP’s pacifier recommendations are not unique,” says author Elizabeth Damato, Ph.D., RN. “A variety of studies have indicated that pacifier use lowers the risk of SIDS, and several other countries have made similar recommendations.” She stresses, however, that parents must be counseled on how to use pacifiers safely.
“Pacifiers shouldn’t be used before the age of one month in breastfed infants to avoid the disruption of regular feeding habits,” says Damato. “Also, infants should not be forced to take a pacifier and parents should not reinsert it once the infant falls asleep.” Parents should also avoid using homemade pacifiers, avoid strings or cords to secure the pacifier to the child, and regularly clean and replace pacifiers.
Even though evidence is mounting that pacifiers help to prevent SIDS, no one knows why. “Because SIDS happens so rarely, it is difficult to do large-scale controlled studies to determine why pacifiers might help,” says Damato. “However, because the risk for serious side effects is greatly reduced if pacifiers are used properly, they are a safe and sensible option in the battle against SIDS.”
Belly fat may drive inflammatory processes and disease
As scientists learn more about the key role of inflammation in diabetes, heart disease and other disorders, new research from Washington University School of Medicine in St. Louis suggests that fat in the belly may be an important promoter of that inflammation.
Excess fat is known to be associated with disease, but now the researchers have confirmed that fat cells inside the abdomen are secreting molecules that increase inflammation. It's the first evidence of a potential mechanistic link between abdominal fat and systemic inflammation.
For years, scientists have been aware of a relationship between disease risk and excess belly fat. "Apple-shaped" people, who carry fat in the abdomen, have a higher risk of heart disease, diabetes and other problems than "pear-shaped" people, who tend to store fat in the hips and thighs. Too much abdominal fat is associated with a defect in the body's response to insulin. During medical exams, some physicians measure waist circumference to identify patients at increased risk for these problems.
Not just any belly fat will cause inflammation, however. Back in 2004, Washington University investigators found that removing abdominal fat with liposuction did not provide the metabolic benefits normally associated with similar amounts of fat loss induced by dieting or exercising.
"Despite removing large amounts of subcutaneous fat from beneath the skin — about 20 percent of a person's total body fat mass — there were no beneficial medical effects," says Samuel Klein, M.D., the Danforth Professor of Medicine and Nutritional Science and the senior investigator on both studies. "These results demonstrated that decreasing fat mass by surgery, which removes billions of fat cells, does not provide the metabolic benefits seen when fat mass is reduced by lowering calorie intake, which shrinks the size of fat cells and decreases the amount of fat inside the abdomen and other tissues."
In this new study, researchers looked instead at visceral fat — the fat that surrounds the organs in the gut. Unlike subcutaneous fat, visceral fat is not easy to remove surgically because it is very close to the intestines and other internal organs. Since they couldn't just take out the fat, the research team decided to analyze the blood that ran through it to determine whether visceral fat was involved in inflammation or whether, like subcutaneous fat, it was merely a marker of potential problems.
Reporting in the journal Diabetes, the research team says visceral fat likely contributes to increases in systemic inflammation and insulin resistance. They sampled blood from the portal vein in obese patients undergoing gastric bypass surgery and found that visceral fat in the abdomen was secreting high levels of an important inflammatory molecule called interleukin-6 (IL-6) into portal vein blood.
"The portal vein is filled with blood that drains visceral fat," says first author Luigi Fontana, M.D., Ph.D., assistant professor of medicine at Washington University in St. Louis and an investigator at the Istituto Superiore di Sanita, Rome, Italy. "Portal vein blood had levels of IL-6 that were 50 percent higher than blood from the periphery."
Increased IL-6 levels in the portal vein correlated with concentrations of an inflammatory substance called C-reactive protein (CRP) in the body. High CRP levels are related to inflammation, and chronic inflammation is associated with insulin resistance, hypertension, type 2 diabetes and atherosclerosis, among other things.
"These data support the notion that visceral fat produces inflammatory cytokines that contribute to insulin resistance and cardiovascular disease," says Klein.
Klein, Fontana and J. Christopher Eagon, M.D., assistant professor of surgery, looked at blood samples from 25 patients. All were extremely obese, and all were undergoing gastric bypass surgery. They took blood from the portal vein and from the radial artery in the arm and found differences in levels of IL-6 between the samples.
Fontana believes the findings help explain how visceral fat can lead to inflammation, insulin resistance and other metabolic problems. And he says by contributing to inflammation, visceral fat cells in the abdomen may be doing even more than that.
"Many years ago, atherosclerosis was thought to be related to lipids and to the excessive deposit of cholesterol in the arteries," Fontana says. "Nowadays, it's clear that atherosclerosis is an inflammatory disease. There also is evidence that inflammation plays a role in cancer, and there is even evidence that it plays a role in aging. Someday we may learn that visceral fat is involved in those things, too."
Excess fat is known to be associated with disease, but now the researchers have confirmed that fat cells inside the abdomen are secreting molecules that increase inflammation. It's the first evidence of a potential mechanistic link between abdominal fat and systemic inflammation.
For years, scientists have been aware of a relationship between disease risk and excess belly fat. "Apple-shaped" people, who carry fat in the abdomen, have a higher risk of heart disease, diabetes and other problems than "pear-shaped" people, who tend to store fat in the hips and thighs. Too much abdominal fat is associated with a defect in the body's response to insulin. During medical exams, some physicians measure waist circumference to identify patients at increased risk for these problems.
Not just any belly fat will cause inflammation, however. Back in 2004, Washington University investigators found that removing abdominal fat with liposuction did not provide the metabolic benefits normally associated with similar amounts of fat loss induced by dieting or exercising.
"Despite removing large amounts of subcutaneous fat from beneath the skin — about 20 percent of a person's total body fat mass — there were no beneficial medical effects," says Samuel Klein, M.D., the Danforth Professor of Medicine and Nutritional Science and the senior investigator on both studies. "These results demonstrated that decreasing fat mass by surgery, which removes billions of fat cells, does not provide the metabolic benefits seen when fat mass is reduced by lowering calorie intake, which shrinks the size of fat cells and decreases the amount of fat inside the abdomen and other tissues."
In this new study, researchers looked instead at visceral fat — the fat that surrounds the organs in the gut. Unlike subcutaneous fat, visceral fat is not easy to remove surgically because it is very close to the intestines and other internal organs. Since they couldn't just take out the fat, the research team decided to analyze the blood that ran through it to determine whether visceral fat was involved in inflammation or whether, like subcutaneous fat, it was merely a marker of potential problems.
Reporting in the journal Diabetes, the research team says visceral fat likely contributes to increases in systemic inflammation and insulin resistance. They sampled blood from the portal vein in obese patients undergoing gastric bypass surgery and found that visceral fat in the abdomen was secreting high levels of an important inflammatory molecule called interleukin-6 (IL-6) into portal vein blood.
"The portal vein is filled with blood that drains visceral fat," says first author Luigi Fontana, M.D., Ph.D., assistant professor of medicine at Washington University in St. Louis and an investigator at the Istituto Superiore di Sanita, Rome, Italy. "Portal vein blood had levels of IL-6 that were 50 percent higher than blood from the periphery."
Increased IL-6 levels in the portal vein correlated with concentrations of an inflammatory substance called C-reactive protein (CRP) in the body. High CRP levels are related to inflammation, and chronic inflammation is associated with insulin resistance, hypertension, type 2 diabetes and atherosclerosis, among other things.
"These data support the notion that visceral fat produces inflammatory cytokines that contribute to insulin resistance and cardiovascular disease," says Klein.
Klein, Fontana and J. Christopher Eagon, M.D., assistant professor of surgery, looked at blood samples from 25 patients. All were extremely obese, and all were undergoing gastric bypass surgery. They took blood from the portal vein and from the radial artery in the arm and found differences in levels of IL-6 between the samples.
Fontana believes the findings help explain how visceral fat can lead to inflammation, insulin resistance and other metabolic problems. And he says by contributing to inflammation, visceral fat cells in the abdomen may be doing even more than that.
"Many years ago, atherosclerosis was thought to be related to lipids and to the excessive deposit of cholesterol in the arteries," Fontana says. "Nowadays, it's clear that atherosclerosis is an inflammatory disease. There also is evidence that inflammation plays a role in cancer, and there is even evidence that it plays a role in aging. Someday we may learn that visceral fat is involved in those things, too."
Periodontal diseases aggravate pre-diabetic characteristics
54 million Americans have pre-diabetes
Periodontal diseases may contribute to the progression to pre-diabetes, according to a new study that appears in the March issue of the Journal of Periodontology.
Pre-diabetes is a condition in which blood glucose levels are higher than normal, but not high enough to be diagnosed as diabetes. The American Diabetes Association estimates 54 million people in the United States have pre-diabetes, and a significant portion of those people will develop Type 2 diabetes within 10 years.
Researchers from Denmark investigated if having periodontal diseases can influence pre-diabetes and contribute to the progression of diabetes. They found that having periodontal disease can cause someone to develop pre-diabetic characteristics, and probably disturb the glucose regulation of a non-diabetic who has pre-diabetic characteristics, contributing to the progression of Type 2 diabetes. The study, conducted with rat models known to exhibit pre-diabetes characteristics, is believed to be the first to evaluate the relationship between periodontitis and pre-diabetes.
"This study found that having periodontal diseases can alter the metabolic conditions which would probably lead to the progression to pre-diabetic characteristics and Type 2 diabetes," said Dr. Carla Pontes Andersen, Department of Periodontology at the University of Copenhagen.
"We have known that people with diabetes are more susceptible to periodontal diseases and have more severe disease," said Dr. Preston D. Miller, Jr., President of the American Academy of Periodontology. "This breakthrough research shows having periodontal disease may aggravate pre-diabetes which is a precursor for diabetes. These findings underscore the importance of taking good care of your teeth and gums: it may be a simple way to prevent diabetes, or to prevent the progression of diabetes."
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To asses your periodontal health visit www.perio.org and click on "Assess your gum disease risk". To check if you may be at risk of developing diabetes, visit http://www.diabetes.org/risk-test.jsp.
Periodontal diseases may contribute to the progression to pre-diabetes, according to a new study that appears in the March issue of the Journal of Periodontology.
Pre-diabetes is a condition in which blood glucose levels are higher than normal, but not high enough to be diagnosed as diabetes. The American Diabetes Association estimates 54 million people in the United States have pre-diabetes, and a significant portion of those people will develop Type 2 diabetes within 10 years.
Researchers from Denmark investigated if having periodontal diseases can influence pre-diabetes and contribute to the progression of diabetes. They found that having periodontal disease can cause someone to develop pre-diabetic characteristics, and probably disturb the glucose regulation of a non-diabetic who has pre-diabetic characteristics, contributing to the progression of Type 2 diabetes. The study, conducted with rat models known to exhibit pre-diabetes characteristics, is believed to be the first to evaluate the relationship between periodontitis and pre-diabetes.
"This study found that having periodontal diseases can alter the metabolic conditions which would probably lead to the progression to pre-diabetic characteristics and Type 2 diabetes," said Dr. Carla Pontes Andersen, Department of Periodontology at the University of Copenhagen.
"We have known that people with diabetes are more susceptible to periodontal diseases and have more severe disease," said Dr. Preston D. Miller, Jr., President of the American Academy of Periodontology. "This breakthrough research shows having periodontal disease may aggravate pre-diabetes which is a precursor for diabetes. These findings underscore the importance of taking good care of your teeth and gums: it may be a simple way to prevent diabetes, or to prevent the progression of diabetes."
###
To asses your periodontal health visit www.perio.org and click on "Assess your gum disease risk". To check if you may be at risk of developing diabetes, visit http://www.diabetes.org/risk-test.jsp.
Friday, March 9, 2007
Research on prostate cancer
Men over 65 tend to get prostate cancer, the second leading cause of cancer death among American men. Fairfield University looked at research of early stage prostate cancer among older men and whether "watchful waiting" was a reasonable option to aggressive therapy. Health care providers are divided regarding the best treatment options for prostate cancer and, with no definitive agreement; diagnosed men tend to experience more uncertainty in making treatment decisions. One thing is certain, further work is needed to change the perception that delaying treatment, which may actually be the best option in many cases, is an automatic death sentence.
"Publishing research that can positively affect men's health is the focus of American Journal of Men's Health," commented the journal's editor, Demetrius Porche, DNS, APRN. "These two studies exploring men's cancers illustrate that mission and are examples of the types of cutting-edge information each issue will feature."
The article, "Critical Review: Is Watchful Waiting a Viable Management Option for Older Men with Prostate Cancer?," written by Donald E. Bailey Jr., PhD, RN, and Meredith Wallace, PhD, APRN, BC can be accessed free for a limited time at http://jmh.sagepub.com/cgi/reprint/1/1/18
"Publishing research that can positively affect men's health is the focus of American Journal of Men's Health," commented the journal's editor, Demetrius Porche, DNS, APRN. "These two studies exploring men's cancers illustrate that mission and are examples of the types of cutting-edge information each issue will feature."
The article, "Critical Review: Is Watchful Waiting a Viable Management Option for Older Men with Prostate Cancer?," written by Donald E. Bailey Jr., PhD, RN, and Meredith Wallace, PhD, APRN, BC can be accessed free for a limited time at http://jmh.sagepub.com/cgi/reprint/1/1/18
Thursday, March 8, 2007
Omega-3s boost grey matter
Omega-3s boost grey matter, findings may explain why omega-3s seem to improve mood
Omega-3 fatty acids, found in fatty fish like salmon, are associated with increased grey matter volume in areas of the brain commonly linked to mood and behavior according to a University of Pittsburgh study.
Findings will be presented today by Sarah M. Conklin, Ph.D., postdoctoral scholar at the Cardiovascular Behavioral Medicine Program in the department of psychiatry at the University of Pittsburgh, at the American Psychosomatic Society’s Annual Meeting, held in Budapest, Hungary.
Animal research has shown that raising omega-3 intake leads to structural brain changes. In a separate study presented by Dr. Conklin at the society’s meeting last year, Pitt researchers reported that people who had lower blood levels of omega-3 fatty acids were more likely to have a negative outlook and be more impulsive. Conversely, those with higher blood levels of omega-3s were found to be more agreeable and less likely to report mild or moderate symptoms of depression. In the study being presented today, the researchers sought to investigate if grey matter volume was proportionally related to long-chain omega-3 intake in humans, especially in areas of the brain related to mood, helping them attempt to explain the mechanisms behind the improvement in mood often associated with long-chain omega-3 intake.
Researchers interviewed 55 healthy adult participants to determine their average intake of long-chain omega-3 fatty acids. Grey matter volume was evaluated using high-resolution structural MRI. The researchers discovered that participants who had high levels of long-chain omega-3 fatty acid intake had higher volumes of grey matter in areas of the brain associated with emotional arousal and regulation – the bilateral anterior cingulate cortex, the right amygdala and the right hippocampus.
While this finding suggests that omega-3s may promote structural improvement in areas of the brain related to mood and emotion regulation – the same areas where grey matter is reduced in people who have mood disorders such as major depressive disorder – investigators note that more research is needed to determine whether fish consumption actually causes changes in the brain
Omega-3 fatty acids, found in fatty fish like salmon, are associated with increased grey matter volume in areas of the brain commonly linked to mood and behavior according to a University of Pittsburgh study.
Findings will be presented today by Sarah M. Conklin, Ph.D., postdoctoral scholar at the Cardiovascular Behavioral Medicine Program in the department of psychiatry at the University of Pittsburgh, at the American Psychosomatic Society’s Annual Meeting, held in Budapest, Hungary.
Animal research has shown that raising omega-3 intake leads to structural brain changes. In a separate study presented by Dr. Conklin at the society’s meeting last year, Pitt researchers reported that people who had lower blood levels of omega-3 fatty acids were more likely to have a negative outlook and be more impulsive. Conversely, those with higher blood levels of omega-3s were found to be more agreeable and less likely to report mild or moderate symptoms of depression. In the study being presented today, the researchers sought to investigate if grey matter volume was proportionally related to long-chain omega-3 intake in humans, especially in areas of the brain related to mood, helping them attempt to explain the mechanisms behind the improvement in mood often associated with long-chain omega-3 intake.
Researchers interviewed 55 healthy adult participants to determine their average intake of long-chain omega-3 fatty acids. Grey matter volume was evaluated using high-resolution structural MRI. The researchers discovered that participants who had high levels of long-chain omega-3 fatty acid intake had higher volumes of grey matter in areas of the brain associated with emotional arousal and regulation – the bilateral anterior cingulate cortex, the right amygdala and the right hippocampus.
While this finding suggests that omega-3s may promote structural improvement in areas of the brain related to mood and emotion regulation – the same areas where grey matter is reduced in people who have mood disorders such as major depressive disorder – investigators note that more research is needed to determine whether fish consumption actually causes changes in the brain
Garlic Protects Against Cancer
New findings by a Queen's University research team dispel the popular notion that eating so-called "natural" foods will protect against cancer.
In fact, certain types of common foods and alcoholic beverages such as wine, cheese, yogurt and bread contain trace amounts of carcinogens.
Led by Dr. Poh-Gek Forkert of Queen's Department of Anatomy and Cell Biology, the team has discovered that a naturally-occurring carcinogen found in alcoholic beverages and fermented foods causes DNA modification and mutations, ultimately leading to abnormal cell growth and lung cancer. Her research also shows that a component of garlic significantly reduces these changes.
The most recent Queen's findings are published on-line today in the journal, Carcinogenesis. This is the third in a series of four related papers: two of the companion papers are published on-line in the International Journal of Cancer and Drug Metabolism and Disposition.
The researchers are studying the effects of treatment with vinyl carbamate in mice. This substance is derived from ethyl carbamate (urethane), a by-product of fermentation found in alcoholic beverages, and fermented foods like cheese, yogurt and bread. It is also present naturally in tobacco.
Urethane is now labeled as a potential human carcinogen by both the World Health Organization and the International Agency for Research on Cancer.
In these studies, the mice were administered a single high dose of the carcinogenic chemical. Human exposure differs from that in mice in that it is much lower, and occurs over a prolonged period of time. A question has been raised regarding the effect on people who ingest low levels of the chemical daily over many years, and perhaps over a lifetime.
"We believe that people should not be apprehensive about consuming these foods and beverages: if consumed at low levels, they probably don't pose a risk. It might be prudent, however, to have a varied diet and to limit drinking certain alcoholic beverages," says Dr. Forkert. "And include garlic!" she adds.
In fact, certain types of common foods and alcoholic beverages such as wine, cheese, yogurt and bread contain trace amounts of carcinogens.
Led by Dr. Poh-Gek Forkert of Queen's Department of Anatomy and Cell Biology, the team has discovered that a naturally-occurring carcinogen found in alcoholic beverages and fermented foods causes DNA modification and mutations, ultimately leading to abnormal cell growth and lung cancer. Her research also shows that a component of garlic significantly reduces these changes.
The most recent Queen's findings are published on-line today in the journal, Carcinogenesis. This is the third in a series of four related papers: two of the companion papers are published on-line in the International Journal of Cancer and Drug Metabolism and Disposition.
The researchers are studying the effects of treatment with vinyl carbamate in mice. This substance is derived from ethyl carbamate (urethane), a by-product of fermentation found in alcoholic beverages, and fermented foods like cheese, yogurt and bread. It is also present naturally in tobacco.
Urethane is now labeled as a potential human carcinogen by both the World Health Organization and the International Agency for Research on Cancer.
In these studies, the mice were administered a single high dose of the carcinogenic chemical. Human exposure differs from that in mice in that it is much lower, and occurs over a prolonged period of time. A question has been raised regarding the effect on people who ingest low levels of the chemical daily over many years, and perhaps over a lifetime.
"We believe that people should not be apprehensive about consuming these foods and beverages: if consumed at low levels, they probably don't pose a risk. It might be prudent, however, to have a varied diet and to limit drinking certain alcoholic beverages," says Dr. Forkert. "And include garlic!" she adds.
Mercury contamination of fish
The health risks posed by mercury contaminated fish is sufficient to warrant issuing a worldwide general warning to the public — especially children and women of childbearing age-to be careful about how much and which fish they eat. That is one of the key findings comprising "The Madison Declaration on Mercury Pollution" published today in a special issue of the international science journal Ambio.
Developed at the Eighth International Conference on Mercury as a Global Pollutant last August in Madison, Wis., the declaration is a synopsis of the latest scientific knowledge about the danger posed by mercury pollution. It presents 33 principal findings from five synthesis papers prepared by the world's leading mercury scientists and published in the same issue of Ambio. The declaration and supporting papers summarize what is currently known about the sources and movement of mercury in the atmosphere, the socioeconomic and health effects of mercury pollution on human populations, and its effects on the world's fisheries and wildlife.
Five other major findings in the declaration were:
On average, three times more mercury is falling from the sky today than before the Industrial Revolution 200 years ago as a result of the increasing use of mercury and industrial emissions.
The uncontrolled use of mercury in small-scale gold mining is contaminating thousands of sites around the world, posing long-term health risks to an estimated 50 million inhabitants of mining regions. These activities alone contribute more than 10 percent of the mercury in Earth's atmosphere attributable to human activities today.
Little is known about the behavior of mercury in marine ecosystems and methylmercury in marine fish, the ingestion of which is the primary way most people at all levels of society worldwide are exposed to this highly toxic form of mercury.
Methylmercury exposure now constitutes a public health problem in most regions of the world.
Methylmercury levels in fish-eating birds and mammals in some parts of the world are reaching toxic levels, which may lead to population declines in these species and possibly in fish populations as well.
"The policy implications of these findings are clear," said James Wiener, a Wisconsin Distinguished Professor at the University of Wisconsin-La Crosse who served as technical chair for last summer's conference. "The declaration and detailed analyses presented in the five supporting papers clearly show that effective national and international policies are needed to combat this global problem." Published by the Royal Swedish Academy of Sciences, Ambio (www.ambio.kva.se) is widely recognized as an important international forum for debate on scientific, social, economic and cultural issues affecting the human environment.
Wiener said the Madison Declaration summarizes a year-long effort by many of the world's leading mercury scientists, assembled into four expert panels, to review and synthesize the major mercury science findings. Every member of all four scientific panels endorsed the declaration, he said. Wiener added that all 1,150 participants at the conference were invited to express their confidence in the experts' findings, and the vast majority of those who did so agreed with the experts' conclusions.
Other major findings in the declaration include:
Increased mercury emissions from developing countries over the last 30 years have offset decreased emissions from developed nations.
There is now solid scientific evidence of methylmercury's toxic health effects, particularly to the human fetus.
New evidence indicates that methylmercury exposure may increase the risk of cardiovascular disease, particularly in adult men.
Increasing mercury concentrations are now being found in a number of fish-eating wildlife species in remote areas of the planet.
The actual socioeconomic costs of mercury pollution are probably much greater than estimated because existing economic analyses don't consider mercury's impacts on ecosystems and wildlife.
The concentration of methylmercury in fish in freshwater and coastal ecosystems can be expected to decline with reduced mercury inputs; however, the rate of decline is expected to vary among water bodies, depending on the characteristics of a particular ecosystem.
Developed at the Eighth International Conference on Mercury as a Global Pollutant last August in Madison, Wis., the declaration is a synopsis of the latest scientific knowledge about the danger posed by mercury pollution. It presents 33 principal findings from five synthesis papers prepared by the world's leading mercury scientists and published in the same issue of Ambio. The declaration and supporting papers summarize what is currently known about the sources and movement of mercury in the atmosphere, the socioeconomic and health effects of mercury pollution on human populations, and its effects on the world's fisheries and wildlife.
Five other major findings in the declaration were:
On average, three times more mercury is falling from the sky today than before the Industrial Revolution 200 years ago as a result of the increasing use of mercury and industrial emissions.
The uncontrolled use of mercury in small-scale gold mining is contaminating thousands of sites around the world, posing long-term health risks to an estimated 50 million inhabitants of mining regions. These activities alone contribute more than 10 percent of the mercury in Earth's atmosphere attributable to human activities today.
Little is known about the behavior of mercury in marine ecosystems and methylmercury in marine fish, the ingestion of which is the primary way most people at all levels of society worldwide are exposed to this highly toxic form of mercury.
Methylmercury exposure now constitutes a public health problem in most regions of the world.
Methylmercury levels in fish-eating birds and mammals in some parts of the world are reaching toxic levels, which may lead to population declines in these species and possibly in fish populations as well.
"The policy implications of these findings are clear," said James Wiener, a Wisconsin Distinguished Professor at the University of Wisconsin-La Crosse who served as technical chair for last summer's conference. "The declaration and detailed analyses presented in the five supporting papers clearly show that effective national and international policies are needed to combat this global problem." Published by the Royal Swedish Academy of Sciences, Ambio (www.ambio.kva.se) is widely recognized as an important international forum for debate on scientific, social, economic and cultural issues affecting the human environment.
Wiener said the Madison Declaration summarizes a year-long effort by many of the world's leading mercury scientists, assembled into four expert panels, to review and synthesize the major mercury science findings. Every member of all four scientific panels endorsed the declaration, he said. Wiener added that all 1,150 participants at the conference were invited to express their confidence in the experts' findings, and the vast majority of those who did so agreed with the experts' conclusions.
Other major findings in the declaration include:
Increased mercury emissions from developing countries over the last 30 years have offset decreased emissions from developed nations.
There is now solid scientific evidence of methylmercury's toxic health effects, particularly to the human fetus.
New evidence indicates that methylmercury exposure may increase the risk of cardiovascular disease, particularly in adult men.
Increasing mercury concentrations are now being found in a number of fish-eating wildlife species in remote areas of the planet.
The actual socioeconomic costs of mercury pollution are probably much greater than estimated because existing economic analyses don't consider mercury's impacts on ecosystems and wildlife.
The concentration of methylmercury in fish in freshwater and coastal ecosystems can be expected to decline with reduced mercury inputs; however, the rate of decline is expected to vary among water bodies, depending on the characteristics of a particular ecosystem.
Cholesterol could be key to successful pregnancy
Small amounts of alcohol can interfere with the growth of a fetus, but added cholesterol may help prevent a wide array of neurological and physical defects from alcohol exposure, according to a new study in laboratory fish.
Cholesterol is so important to fetal development that pregnant women who do not have high enough cholesterol levels are at increased risk of having babies with developmental problems, even without consuming alcohol. Researchers at Duke University Medical Center, led by Yin-Xiong Li, MD., Ph.D., found that alcohol, even in small amounts, blocks the ability of cholesterol to orchestrate the complex series of events involved in regulating cell fates and organ development in the embryo. Encouragingly, the researchers also found that giving supplemental cholesterol to zebrafish embryos exposed to alcohol restored normal development.
Also, he said the findings provide further credence to current practice of ensuring that pregnant women should not lower their cholesterol too low. A recent study found that women who took cholesterol-lowering drugs known as statins were at greater risk of giving birth to babies with developmental problems.
Fetal alcohol syndrome is a term to describe an array of developmental defects affecting the nervous and cardiovascular systems. The syndrome also can lead to growth retardation, facial abnormalities and lowered mental functioning. It is estimated that approximately 100 babies are born in the United States each day with some degree of alcohol induced birth defects, at an annual cost of $10 billion to the health care system.
What alcohol does is interfere with a precisely orchestrated biochemical signaling pathway that guides fetal development. Cholesterol is essential for a single pathway that governs the pattern of tissue development and it is vulnerable to the effects of alcohol.
"This new insight into the molecular basis of fetal alcohol syndrome could have far-reaching implications and suggests new prenatal care that might prevent the developmental defects caused by alcohol consumed during pregnancy," Li said.
The researchers published the findings in the March 2007 issue of the journal Laboratory Investigation. The research was supported by the National Institutes of Health and the American Heart Association.
Li said that the keys to fetal alcohol syndrome’s severity are the amount of alcohol consumed, the duration of the consumption and the timing of the pregnancy. For example, alcohol consumed by a mother with a one-month-old fetus could alter the development of the brain; at four to eight weeks, facial structures, heart and eyesight could be affected. Two to three months into fetal development, alcohol consumption could lead to the growth of extra digits.
"The amount of alcohol consumed is important as well," Li said. "Even the equivalent of one 12-ounce beer, consumed at the wrong time, could disrupt the signaling pathway and lead to a defect."
The team also found that increased amounts of alcohol exposure by the fetus led to increased severity of the syndrome.
Li pointed out that the findings could have other theoretical implications as well. He said giving alcoholics supplemental cholesterol could help slow down or prevent the occurrence of alcoholic liver disease, even chronic alcoholic induced cirrhosis, characterized by replacement of liver tissue by scar tissue, leading to progressive loss of liver function.
Cholesterol is so important to fetal development that pregnant women who do not have high enough cholesterol levels are at increased risk of having babies with developmental problems, even without consuming alcohol. Researchers at Duke University Medical Center, led by Yin-Xiong Li, MD., Ph.D., found that alcohol, even in small amounts, blocks the ability of cholesterol to orchestrate the complex series of events involved in regulating cell fates and organ development in the embryo. Encouragingly, the researchers also found that giving supplemental cholesterol to zebrafish embryos exposed to alcohol restored normal development.
Also, he said the findings provide further credence to current practice of ensuring that pregnant women should not lower their cholesterol too low. A recent study found that women who took cholesterol-lowering drugs known as statins were at greater risk of giving birth to babies with developmental problems.
Fetal alcohol syndrome is a term to describe an array of developmental defects affecting the nervous and cardiovascular systems. The syndrome also can lead to growth retardation, facial abnormalities and lowered mental functioning. It is estimated that approximately 100 babies are born in the United States each day with some degree of alcohol induced birth defects, at an annual cost of $10 billion to the health care system.
What alcohol does is interfere with a precisely orchestrated biochemical signaling pathway that guides fetal development. Cholesterol is essential for a single pathway that governs the pattern of tissue development and it is vulnerable to the effects of alcohol.
"This new insight into the molecular basis of fetal alcohol syndrome could have far-reaching implications and suggests new prenatal care that might prevent the developmental defects caused by alcohol consumed during pregnancy," Li said.
The researchers published the findings in the March 2007 issue of the journal Laboratory Investigation. The research was supported by the National Institutes of Health and the American Heart Association.
Li said that the keys to fetal alcohol syndrome’s severity are the amount of alcohol consumed, the duration of the consumption and the timing of the pregnancy. For example, alcohol consumed by a mother with a one-month-old fetus could alter the development of the brain; at four to eight weeks, facial structures, heart and eyesight could be affected. Two to three months into fetal development, alcohol consumption could lead to the growth of extra digits.
"The amount of alcohol consumed is important as well," Li said. "Even the equivalent of one 12-ounce beer, consumed at the wrong time, could disrupt the signaling pathway and lead to a defect."
The team also found that increased amounts of alcohol exposure by the fetus led to increased severity of the syndrome.
Li pointed out that the findings could have other theoretical implications as well. He said giving alcoholics supplemental cholesterol could help slow down or prevent the occurrence of alcoholic liver disease, even chronic alcoholic induced cirrhosis, characterized by replacement of liver tissue by scar tissue, leading to progressive loss of liver function.
Warning Signs of Kidney Disease in Children
Kidney Disease in Children: Common But Treatable; Parents Should Learn to Spot the Telltale Signs, Children's Center Doctors Urge
"Kidney disease occurs more often than we think, but it is also more treatable than we used to think, especially when caught early," says Barbara Fivush, M.D., director of nephrology at the Johns Hopkins Children's Center. "Children and adolescents should be monitored carefully because kidney disease that seems to suddenly strike young adults often has its roots in childhood."
Kidney disease develops silently and all too often manifests its presence only when it's far too late to stop the progressive loss in kidney function that will require dialysis or transplantation. More than one-third of kidney transplant patients in 2001 were between the ages of 20 and 44. Many of them likely developed renal disease in childhood, say doctors from the Children's Center.
March is kidney awareness month. On March 8, World Kidney Day, doctors want to remind parents that timely detection of kidney problems in early childhood and adolescence is the best way to curb kidney damage and even reverse some of it.
These telltale signs of early kidney disease should prompt a visit to the doctor.
- Swelling (even mild) of the hands and feet and/or puffiness around the eyes
- Decreased or increased frequency of urination
- Long-lasting changes in the color and appearance of urine (foamy urine suggests the presence of protein)
- Headaches resulting from high blood pressure
The best way to determine kidney function is to measure glomerular filtration rate (GFR), which estimates the speed at which kidneys filter waste material from the blood. To determine GFR, your doctors monitor blood levels of the substance creatinine. The higher the creatinine level, the higher the likelihood that the kidneys are not filtering at normal speed. In addition to blood tests, urinalysis can detect protein and/or blood in the urine-also signs of kidney disease.
"If your child has any signs or symptoms that suggest kidney disease, you should talk to your pediatrician and obtain blood studies," Fivush says.
Systemic diseases such as diabetes or lupus put children at higher risk for kidney damage; they should be monitored regularly.
Unrecognized kidney disease places people at greater risk for high blood pressure, heart disease and stroke. Researchers estimate that 650,000 Americans will develop end-stage renal disease by 2010, costing the health care system $28 billion a year. More then 11 percent of Americans over the age of 20 (more than 19 million) have some form of chronic kidney damage, according to recent estimates by the National Institutes of Health. Each year, about 5,000 children in the United States develop end-stage kidney disease and require a transplant.
"Kidney disease occurs more often than we think, but it is also more treatable than we used to think, especially when caught early," says Barbara Fivush, M.D., director of nephrology at the Johns Hopkins Children's Center. "Children and adolescents should be monitored carefully because kidney disease that seems to suddenly strike young adults often has its roots in childhood."
Kidney disease develops silently and all too often manifests its presence only when it's far too late to stop the progressive loss in kidney function that will require dialysis or transplantation. More than one-third of kidney transplant patients in 2001 were between the ages of 20 and 44. Many of them likely developed renal disease in childhood, say doctors from the Children's Center.
March is kidney awareness month. On March 8, World Kidney Day, doctors want to remind parents that timely detection of kidney problems in early childhood and adolescence is the best way to curb kidney damage and even reverse some of it.
These telltale signs of early kidney disease should prompt a visit to the doctor.
- Swelling (even mild) of the hands and feet and/or puffiness around the eyes
- Decreased or increased frequency of urination
- Long-lasting changes in the color and appearance of urine (foamy urine suggests the presence of protein)
- Headaches resulting from high blood pressure
The best way to determine kidney function is to measure glomerular filtration rate (GFR), which estimates the speed at which kidneys filter waste material from the blood. To determine GFR, your doctors monitor blood levels of the substance creatinine. The higher the creatinine level, the higher the likelihood that the kidneys are not filtering at normal speed. In addition to blood tests, urinalysis can detect protein and/or blood in the urine-also signs of kidney disease.
"If your child has any signs or symptoms that suggest kidney disease, you should talk to your pediatrician and obtain blood studies," Fivush says.
Systemic diseases such as diabetes or lupus put children at higher risk for kidney damage; they should be monitored regularly.
Unrecognized kidney disease places people at greater risk for high blood pressure, heart disease and stroke. Researchers estimate that 650,000 Americans will develop end-stage renal disease by 2010, costing the health care system $28 billion a year. More then 11 percent of Americans over the age of 20 (more than 19 million) have some form of chronic kidney damage, according to recent estimates by the National Institutes of Health. Each year, about 5,000 children in the United States develop end-stage kidney disease and require a transplant.
Wednesday, March 7, 2007
Sports and Unhealthful Weight Control Behaviors among Adolescents
Participation by adolescents, especially males, in sports emphasizing weight, such as ballet, gymnastics and wrestling, is strongly associated with both unhealthful weight-control behaviors and steroid use, according to researchers at the University of Minnesota.
The researchers studied more than 4,500 adolescents from 31 public middle and high schools in the Minneapolis/St. Paul area. The students were asked if in the past week or the past year they had engaged in self-induced vomiting, used diet pills or laxatives or engaged in any other extreme weight-control behavior.
The strongest positive associations between weight-related sport participation and unhealthful weight-control behaviors were found in males:
• 5.8 percent of males who reported participation in a weight-related sport had induced vomiting in the past week, compared with 0.9 percent of males who did not participate in a weight-related sport.
• Use of diuretics within the past year was reported by 4.2 percent of males in a weight-related sport compared with 0.8 percent who did not participate in weight-related sports.
For females, vomiting, laxative use and steroid use were significantly associated with weight-related sports participation:
• 6.6 percent of females who participated in a weight-related sport had vomited in the past week compared with 3.2 percent of females who did not.
• Steroid use was reported by 6.5 percent of females who perceived their sport as weight-related, compared to 2.3 percent of females who did not participate in a sport they perceived as weight-related.
“Preventive efforts, targeting parents, coaches and adolescents are needed to decrease this risk,” the researchers conclude.
The researchers studied more than 4,500 adolescents from 31 public middle and high schools in the Minneapolis/St. Paul area. The students were asked if in the past week or the past year they had engaged in self-induced vomiting, used diet pills or laxatives or engaged in any other extreme weight-control behavior.
The strongest positive associations between weight-related sport participation and unhealthful weight-control behaviors were found in males:
• 5.8 percent of males who reported participation in a weight-related sport had induced vomiting in the past week, compared with 0.9 percent of males who did not participate in a weight-related sport.
• Use of diuretics within the past year was reported by 4.2 percent of males in a weight-related sport compared with 0.8 percent who did not participate in weight-related sports.
For females, vomiting, laxative use and steroid use were significantly associated with weight-related sports participation:
• 6.6 percent of females who participated in a weight-related sport had vomited in the past week compared with 3.2 percent of females who did not.
• Steroid use was reported by 6.5 percent of females who perceived their sport as weight-related, compared to 2.3 percent of females who did not participate in a sport they perceived as weight-related.
“Preventive efforts, targeting parents, coaches and adolescents are needed to decrease this risk,” the researchers conclude.
Adolescent Dieting May Predict Weight Gain
Adolescents who go on diets to lose weight may be significantly increasing their odds of gaining weight, say researchers at the University of Minnesota.
The researchers studied results of Project EAT (Eating Among Teens) surveys, conducted in 1999 and 2000, and results of Project EAT II surveys, conducted in 2003 and 2004, to “understand the perplexing finding, that has been reported in several longitudinal studies, whereby dieting predicts greater weight gain over time in adolescents.”
According to information provided by more than 2,500 adolescents, dieting predicted increased binge eating and decreased breakfast consumption among girls, “with a nonsignificant trend toward decreased fruit and vegetable intake.” Among boys, dieting predicted “increased binge eating, decreased physical activity and a trend toward decreased breakfast consumption. These behaviors were also associated with increases in body mass index,” according to the researchers.
The researchers conclude that dieting may lead to weight gain among adolescents in part “via the long-term adoption of behavioral patterns that are counterproductive to weight management.”
The researchers studied results of Project EAT (Eating Among Teens) surveys, conducted in 1999 and 2000, and results of Project EAT II surveys, conducted in 2003 and 2004, to “understand the perplexing finding, that has been reported in several longitudinal studies, whereby dieting predicts greater weight gain over time in adolescents.”
According to information provided by more than 2,500 adolescents, dieting predicted increased binge eating and decreased breakfast consumption among girls, “with a nonsignificant trend toward decreased fruit and vegetable intake.” Among boys, dieting predicted “increased binge eating, decreased physical activity and a trend toward decreased breakfast consumption. These behaviors were also associated with increases in body mass index,” according to the researchers.
The researchers conclude that dieting may lead to weight gain among adolescents in part “via the long-term adoption of behavioral patterns that are counterproductive to weight management.”
Tuesday, March 6, 2007
Whole-grain breakfast cereal = reduced heart failure risk
Whole-grain breakfast cereal associated with reduced heart failure risk
Eating whole-grain breakfast cereals seven or more times per week was associated with a lower risk of heart failure, according to an analysis of the observational Physicians’ Health Study. Researchers presented findings of the study today at the American Heart Association’s 47th Annual Conference on Cardiovascular Disease Epidemiology and Prevention. For the present study, breakfast cereals that contain at least 25 percent oat or bran content were classified as whole grain cereals.
The analysis shows that those who ate a whole-grain breakfast cereal seven or more times per week were less likely (by 28 percent) to develop heart failure over the course of the study than those who never ate such cereal. The risk of heart failure decreased by 22 percent in those who ate a whole-grain breakfast cereal from two to six times per week and by 14 percent in those who ate a whole-grain breakfast cereal up to once per week.
According to researchers, if this data is confirmed by other studies, a healthy diet including whole-grain breakfast cereals along with other measures may help reduce the risk of heart failure.
"There are good and powerful arguments for eating a whole-grain cereal for breakfast," said Luc Djoussé, M.D., M.P.H., D.Sc., lead author of the study and assistant professor of medicine in the Division of Aging at Brigham & Women’s Hospital and Harvard Medical School in Boston, Mass. "The significant health benefits of whole-grain cereal are not just for kids, but also for adults. A whole-grain, high-fiber breakfast may lower blood pressure and bad cholesterol and prevent heart attacks."
Djoussé urges the general public to consider eating a regular whole-grain, high fiber breakfast for its overall health benefits.
In the Physicians’ Health Study, the majority of the physicians in the study ate whole-grain cereals rather than refined cereals. Whole grains are rich in vitamins, minerals, and anti-oxidants and have a high fiber content. Of 10,469 physicians reporting cereal consumption at baseline, 8,266 (79 percent) ate whole-grain cereals compared to 2,203 (21 percent) who ate refined cereals.
Among the physicians who ate whole-grain breakfast cereals, 2,873 (35 percent) said they ate them seven or more times per week; 3,240 (39 percent) said two to six times per week; and 2,153 (26 percent) said they ate up to one cereal serving per week.
The findings reported here were based on annual detailed questionnaires about major heart events and reported breakfast cereal consumption at baseline. However, the results did not change when possible changes in cereal consumption over time (assessed at 18 weeks; two years; four years; six years; eight years; and ten years) were taken into account. Researchers conducted the study from 1982 to 2006. The average age of physicians in the study at baseline was 53.7 years. Djoussé hopes the findings of the Physicians’ Health Study will encourage the general population to eat heart-healthy diets.
"The Physicians’ Health Study shows that even in a population with overall healthy behavior, it is possible to see less heart failure in those who eat a whole-grain cereal breakfast," Djoussé said.
In the United States, foods considered "whole grain" contain 51 percent or more whole grain ingredients by weight per reference amount customarily consumed.
Eating whole-grain breakfast cereals seven or more times per week was associated with a lower risk of heart failure, according to an analysis of the observational Physicians’ Health Study. Researchers presented findings of the study today at the American Heart Association’s 47th Annual Conference on Cardiovascular Disease Epidemiology and Prevention. For the present study, breakfast cereals that contain at least 25 percent oat or bran content were classified as whole grain cereals.
The analysis shows that those who ate a whole-grain breakfast cereal seven or more times per week were less likely (by 28 percent) to develop heart failure over the course of the study than those who never ate such cereal. The risk of heart failure decreased by 22 percent in those who ate a whole-grain breakfast cereal from two to six times per week and by 14 percent in those who ate a whole-grain breakfast cereal up to once per week.
According to researchers, if this data is confirmed by other studies, a healthy diet including whole-grain breakfast cereals along with other measures may help reduce the risk of heart failure.
"There are good and powerful arguments for eating a whole-grain cereal for breakfast," said Luc Djoussé, M.D., M.P.H., D.Sc., lead author of the study and assistant professor of medicine in the Division of Aging at Brigham & Women’s Hospital and Harvard Medical School in Boston, Mass. "The significant health benefits of whole-grain cereal are not just for kids, but also for adults. A whole-grain, high-fiber breakfast may lower blood pressure and bad cholesterol and prevent heart attacks."
Djoussé urges the general public to consider eating a regular whole-grain, high fiber breakfast for its overall health benefits.
In the Physicians’ Health Study, the majority of the physicians in the study ate whole-grain cereals rather than refined cereals. Whole grains are rich in vitamins, minerals, and anti-oxidants and have a high fiber content. Of 10,469 physicians reporting cereal consumption at baseline, 8,266 (79 percent) ate whole-grain cereals compared to 2,203 (21 percent) who ate refined cereals.
Among the physicians who ate whole-grain breakfast cereals, 2,873 (35 percent) said they ate them seven or more times per week; 3,240 (39 percent) said two to six times per week; and 2,153 (26 percent) said they ate up to one cereal serving per week.
The findings reported here were based on annual detailed questionnaires about major heart events and reported breakfast cereal consumption at baseline. However, the results did not change when possible changes in cereal consumption over time (assessed at 18 weeks; two years; four years; six years; eight years; and ten years) were taken into account. Researchers conducted the study from 1982 to 2006. The average age of physicians in the study at baseline was 53.7 years. Djoussé hopes the findings of the Physicians’ Health Study will encourage the general population to eat heart-healthy diets.
"The Physicians’ Health Study shows that even in a population with overall healthy behavior, it is possible to see less heart failure in those who eat a whole-grain cereal breakfast," Djoussé said.
In the United States, foods considered "whole grain" contain 51 percent or more whole grain ingredients by weight per reference amount customarily consumed.
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