Eating foods containing flavonoids -- orange juice, in this case -- along with a high-fat, high-carbohydrate fast-food meal neutralizes the oxidative and inflammatory stress generated by the unhealthy food and helps prevent blood vessel damage, a new study by University at Buffalo endocrinologists shows.
Free radicals, or reactive oxygen species, are known to induce inflammation in blood vessel linings and contribute to the risk of heart attack and stroke. Study researchers say the potent preventative effect of orange juice likely is linked to its heavy load of the flavonoids naringenin and hesperidin, which are major antioxidants.
"Our data show, for the first time to our knowledge, that drinking orange juice with a meal high in fat and carbohydrates prevented the marked increases in reactive oxygen species and other inflammatory agents," says UB's Husam Ghanim, PhD, first author on the study.
"This did not happen when participants drank water or a sugary drink with the meal," he says. "These issues of inflammation following a meal are important because the resultant high glucose and high triglycerides are known to be related to the development of cardiovascular events."
Ghanim is a research assistant professor in UB's Division of Endocrinology, Diabetes and Metabolism. The study appears in the March issue of the American Journal of Clinical Nutrition and appeared online ahead of print.
The study involved three groups of 10 normal-weight healthy men and women between the ages of 20 and 40. After an overnight fast, participants ate a 900-calorie breakfast composed of an egg "muffin" sandwich, a sausage "muffin" sandwich and a serving of hash browns. The meal contained 81 grams of carbohydrates, 51 grams of fat and 32 grams protein.
Along with the breakfast, one group drank 300 calories of "not-from-concentrate" orange juice, a second group drank a 300-calorie glucose drink and the third group drank an equal amount of water. All participants were given 15 minutes to finish their food and drink. Blood samples were collected before the meal and at 1, 3 and 5 hours afterwards. There was no significant difference in inflammatory mediators among the groups before the meal.
Analysis of the samples after the meal showed that oxygen free radicals increased an average of 62 percent with water, 63 percent with the glucose and 47 percent with orange juice. There also was an increase in blood components known as toll-like receptors, which play an important role in the development of inflammation, atherosclerosis, obesity, insulin resistance, and injury to cardiac cells than can occur after a blocked vessel is reopened.
Orange juice also prevented a significant increase in SOCS-3, an important mediator of insulin resistance, which contributes to development of type 2 diabetes.
"These data emphasize that a high-fat, high-carbohydrate meal is profoundly and rapidly proinflammatory, and that this process occurs at the cellular and molecular level," says Paresh Dandona, MD, UB distinguished professor of medicine, director of the Diabetes-Endocrinology Center of Western New York at Kaleida Health and senior author on the study.
"In addition, specific proinflammatory genes are activated after the intake of glucose and a high-fat, high-carbohydrate meal, and these changes are observed in mononuclear cells that participate in vascular inflammation and insulin resistance," he says.
"These observations extend our previous work showing oxidative and inflammatory stress following such meals by demonstrating a remarkable increase in the mediators of insulin resistance after a single meal, and the equally remarkable prevention of these changes following the intake of orange juice."
Dandona emphasizes that vascular inflammation is an essential component of atherosclerosis, and that this inflammation may become permanent if a person consumes similar meals regularly.
"The choice of safe foods that are not proinflammatory may provide protection from the unending cycle of postprandial and cumulative inflammation," he says. "This choice may lower the risk of atherosclerosis and resistance to insulin
Tuesday, March 30, 2010
Possible Link Between Vitamins, Breast Cancer?
A study recently published in the American Journal of Clinical Nutrition has found that older women who use multivitamins might be more likely to develop breast cancer than those who do not use the supplements. Or it might just be a statistical anomaly. Or people may use multivitamins because of other unhealthful behaviors - such as lack of a good diet.
Over 35,000 Swedish women, ages 49 to 83, were interviewed over a 10-year time span. All of the women were cancer-free at the beginning of the study, but 974 of them had developed the disease within the decade.
Those who used multivitamins were 19-percent more likely than non-users to develop cancer, though only 293 of over 9,000 vitamin users developed the ailment. In comparison, 681 of the more than 26,000 women who did not use vitamins were ultimately diagnosed with breast cancer.
Over 35,000 Swedish women, ages 49 to 83, were interviewed over a 10-year time span. All of the women were cancer-free at the beginning of the study, but 974 of them had developed the disease within the decade.
Those who used multivitamins were 19-percent more likely than non-users to develop cancer, though only 293 of over 9,000 vitamin users developed the ailment. In comparison, 681 of the more than 26,000 women who did not use vitamins were ultimately diagnosed with breast cancer.
Chocolate reduces blood pressure and risk of heart disease
Chocolate may be good for you – at least in small quantities and preferably if it's dark chocolate – according to research that shows just one small square of chocolate a day can lower your blood pressure and reduce your risk of heart disease. The study is published online today (Wednesday 31 March) in the European Heart Journal [1].
Researchers in Germany followed 19,357 people, aged between 35 and 65, for at least ten years and found that those who ate the most amount of chocolate – an average of 7.5 grams a day – had lower blood pressure and a 39% lower risk of having a heart attack or stroke compared to those who ate the least amount of chocolate – an average of 1.7 grams a day. The difference between the two groups amounts to six grams of chocolate: the equivalent of less than one small square of a 100g bar.
Dr Brian Buijsse, a nutritional epidemiologist at the German Institute of Human Nutrition, Nuthetal, Germany, who led the research said: "People who ate the most amount of chocolate were at a 39% lower risk than those with the lowest chocolate intakes. To put it in terms of absolute risk, if people in the group eating the least amount of chocolate (of whom 219 per 10,000 had a heart attack or stroke) increased their chocolate intake by six grams a day, 85 fewer heart attacks and strokes per 10,000 people could be expected to occur over a period of about ten years. If the 39% lower risk is generalised to the general population, the number of avoidable heart attacks and strokes could be higher because the absolute risk in the general population is higher."[2]
However, he warned that it was important people ensured that eating chocolate did not increase their overall intake of calories or reduce their consumption of healthy foods. "Small amounts of chocolate may help to prevent heart disease, but only if it replaces other energy-dense food, such as snacks, in order to keep body weight stable," he said.
The people in the study were participants in the Potsdam arm of the European Prospective Investigation into Cancer (EPIC). They received medical checks, including blood pressure, height and weight measurements at the start of the study between 1994-1998, and they also answered questions about their diet, lifestyle and health. They were asked how frequently they ate a 50g bar of chocolate, and they could say whether they ate half a bar, or one, two or three bars. They were not asked about whether the chocolate was white, milk or dark chocolate; however, the researchers asked a sub-set of 1,568 participants to recall their chocolate intake over a 24-hour period and to indicate which type of chocolate they ate. This gave an indication of the proportions that might be expected in the whole study. In this sub-set, 57% ate milk chocolate, 24% dark chocolate and 2% white chocolate.
In follow-up questionnaires, sent out every two or three years until December 2006, the study participants were asked whether they had had a heart attack or stroke, information which was subsequently verified by medical records from general physicians or hospitals. Death certificates from those who had died were also used to identify heart attacks and strokes.
The researchers allocated the participants to four groups (quartiles) according to their level of chocolate consumption. Those in the top quartile, eating around 7.5g of chocolate a day, had blood pressure that was about 1mm Hg (systolic) and 0.9mm Hg (diastolic) lower than those in the bottom quartile. [3]
"Our hypothesis was that because chocolate appears to have a pronounced effect on blood pressure, therefore chocolate consumption would lower the risk of strokes and heart attacks, with a stronger effect being seen for stroke," explained Dr Buijsse.
This is, in fact, what the study found. During the eight years there were 166 heart attacks (24 fatal) and 136 strokes (12 fatal); people in the top quartile had a 27% reduced risk of heart attacks and nearly half the risk (48%) of strokes, compared with those in the lowest quartile.
The researchers found lower blood pressure due to chocolate consumption at the start of the study explained 12% of the reduced risk of heart attacks and strokes, but even after taking this into account, those in the top quartile still had their risk reduced by a third (32%) compared to those in the bottom quartile over the duration of the study.
Although more research needs to be carried out, the researchers believe that flavanols in cocoa may be the reason why chocolate seems to be good for people's blood pressure and heart health; and since there is more cocoa in dark chocolate, dark chocolate may have a greater effect.
"Flavanols appear to be the substances in cocoa that are responsible for improving the bioavailability of nitric oxide from the cells that line the inner wall of blood vessels – vascular endothelial cells," said Dr Buijsse. "Nitric oxide is a gas that, once released, causes the smooth muscle cells of the blood vessels to relax and widen; this may contribute to lower blood pressure. Nitric oxide also improves platelet function, making the blood less sticky, and makes the vascular endothelium less attractive for white blood cells to attach and stick around."
The authors of the study conclude: "Given these and other promising health effects of cocoa, it is tempting to indulge more in chocolate. Small amounts of chocolate, however, may become part of a diet aimed to prevent CVD [cardiovascular disease] only after confirmation by other observational studies and particularly by randomized trials."
Commenting on the research on behalf of the European Society of Cardiology (ESC), Frank Ruschitzka, Professor of Cardiology, Director of Heart Failure/Transplantation at the University Hospital Zurich, Switzerland, and a Fellow of the ESC, said: "Basic science has demonstrated quite convincingly that dark chocolate particularly, with a cocoa content of at least 70%, reduces oxidative stress and improves vascular and platelet function. However, before you rush to add dark chocolate to your diet, be aware that 100g of dark chocolate contains roughly 500 calories. As such, you may want to subtract an equivalent amount of calories, by cutting back on other foods, to avoid weight gain."
Notes:
[1] "Chocolate consumption in relation to blood pressure and risk of cardiovascular disease in German adults." European Heart Journal. doi:10.1093/eurheartj/ehq068.
[2] Examples of absolute risk are given here to help with understanding the findings; however, the study itself only reports relative risk.
[3] mm Hg = millimetres of mercury (the measure for blood pressure).
Systolic = when the heart's ventricles contract.
Diastolic = when the ventricles relax.
The normal blood pressure for a healthy adult is around 120/80.
Researchers in Germany followed 19,357 people, aged between 35 and 65, for at least ten years and found that those who ate the most amount of chocolate – an average of 7.5 grams a day – had lower blood pressure and a 39% lower risk of having a heart attack or stroke compared to those who ate the least amount of chocolate – an average of 1.7 grams a day. The difference between the two groups amounts to six grams of chocolate: the equivalent of less than one small square of a 100g bar.
Dr Brian Buijsse, a nutritional epidemiologist at the German Institute of Human Nutrition, Nuthetal, Germany, who led the research said: "People who ate the most amount of chocolate were at a 39% lower risk than those with the lowest chocolate intakes. To put it in terms of absolute risk, if people in the group eating the least amount of chocolate (of whom 219 per 10,000 had a heart attack or stroke) increased their chocolate intake by six grams a day, 85 fewer heart attacks and strokes per 10,000 people could be expected to occur over a period of about ten years. If the 39% lower risk is generalised to the general population, the number of avoidable heart attacks and strokes could be higher because the absolute risk in the general population is higher."[2]
However, he warned that it was important people ensured that eating chocolate did not increase their overall intake of calories or reduce their consumption of healthy foods. "Small amounts of chocolate may help to prevent heart disease, but only if it replaces other energy-dense food, such as snacks, in order to keep body weight stable," he said.
The people in the study were participants in the Potsdam arm of the European Prospective Investigation into Cancer (EPIC). They received medical checks, including blood pressure, height and weight measurements at the start of the study between 1994-1998, and they also answered questions about their diet, lifestyle and health. They were asked how frequently they ate a 50g bar of chocolate, and they could say whether they ate half a bar, or one, two or three bars. They were not asked about whether the chocolate was white, milk or dark chocolate; however, the researchers asked a sub-set of 1,568 participants to recall their chocolate intake over a 24-hour period and to indicate which type of chocolate they ate. This gave an indication of the proportions that might be expected in the whole study. In this sub-set, 57% ate milk chocolate, 24% dark chocolate and 2% white chocolate.
In follow-up questionnaires, sent out every two or three years until December 2006, the study participants were asked whether they had had a heart attack or stroke, information which was subsequently verified by medical records from general physicians or hospitals. Death certificates from those who had died were also used to identify heart attacks and strokes.
The researchers allocated the participants to four groups (quartiles) according to their level of chocolate consumption. Those in the top quartile, eating around 7.5g of chocolate a day, had blood pressure that was about 1mm Hg (systolic) and 0.9mm Hg (diastolic) lower than those in the bottom quartile. [3]
"Our hypothesis was that because chocolate appears to have a pronounced effect on blood pressure, therefore chocolate consumption would lower the risk of strokes and heart attacks, with a stronger effect being seen for stroke," explained Dr Buijsse.
This is, in fact, what the study found. During the eight years there were 166 heart attacks (24 fatal) and 136 strokes (12 fatal); people in the top quartile had a 27% reduced risk of heart attacks and nearly half the risk (48%) of strokes, compared with those in the lowest quartile.
The researchers found lower blood pressure due to chocolate consumption at the start of the study explained 12% of the reduced risk of heart attacks and strokes, but even after taking this into account, those in the top quartile still had their risk reduced by a third (32%) compared to those in the bottom quartile over the duration of the study.
Although more research needs to be carried out, the researchers believe that flavanols in cocoa may be the reason why chocolate seems to be good for people's blood pressure and heart health; and since there is more cocoa in dark chocolate, dark chocolate may have a greater effect.
"Flavanols appear to be the substances in cocoa that are responsible for improving the bioavailability of nitric oxide from the cells that line the inner wall of blood vessels – vascular endothelial cells," said Dr Buijsse. "Nitric oxide is a gas that, once released, causes the smooth muscle cells of the blood vessels to relax and widen; this may contribute to lower blood pressure. Nitric oxide also improves platelet function, making the blood less sticky, and makes the vascular endothelium less attractive for white blood cells to attach and stick around."
The authors of the study conclude: "Given these and other promising health effects of cocoa, it is tempting to indulge more in chocolate. Small amounts of chocolate, however, may become part of a diet aimed to prevent CVD [cardiovascular disease] only after confirmation by other observational studies and particularly by randomized trials."
Commenting on the research on behalf of the European Society of Cardiology (ESC), Frank Ruschitzka, Professor of Cardiology, Director of Heart Failure/Transplantation at the University Hospital Zurich, Switzerland, and a Fellow of the ESC, said: "Basic science has demonstrated quite convincingly that dark chocolate particularly, with a cocoa content of at least 70%, reduces oxidative stress and improves vascular and platelet function. However, before you rush to add dark chocolate to your diet, be aware that 100g of dark chocolate contains roughly 500 calories. As such, you may want to subtract an equivalent amount of calories, by cutting back on other foods, to avoid weight gain."
Notes:
[1] "Chocolate consumption in relation to blood pressure and risk of cardiovascular disease in German adults." European Heart Journal. doi:10.1093/eurheartj/ehq068.
[2] Examples of absolute risk are given here to help with understanding the findings; however, the study itself only reports relative risk.
[3] mm Hg = millimetres of mercury (the measure for blood pressure).
Systolic = when the heart's ventricles contract.
Diastolic = when the ventricles relax.
The normal blood pressure for a healthy adult is around 120/80.
Monday, March 29, 2010
One Hour Of Exercise A Day?
*
Journal of the American Medical Association:
Among women consuming a usual diet, physical activity was associated with less weight gain only among women whose BMI was lower than 25. Women successful in maintaining normal weight and gaining fewer than 2.3 kg over 13 years averaged approximately 60 minutes a day of moderate-intensity activity throughout the study. The study involved34 079 healthy US women (mean age, 54.2 years) from 1992-2007.
Journal of the American Medical Association:
Among women consuming a usual diet, physical activity was associated with less weight gain only among women whose BMI was lower than 25. Women successful in maintaining normal weight and gaining fewer than 2.3 kg over 13 years averaged approximately 60 minutes a day of moderate-intensity activity throughout the study. The study involved34 079 healthy US women (mean age, 54.2 years) from 1992-2007.
Friday, March 26, 2010
Flaxseed lowers high cholesterol in men
Ω
A new study from Iowa State University's Nutrition and Wellness Research Center (NWRC) may give men a way to combat high cholesterol without drugs -- if they don't mind sprinkling some flaxseed into their daily diet.
Suzanne Hendrich, an ISU professor in food science and human nutrition, led a study that examined the effects of flaxseed lignan in 90 people diagnosed with high cholesterol. The results showed that consuming at least 150 milligrams of flaxseed lignans per day (about three tablespoons) decreased cholesterol in men, but not women, by just under 10 percent over the three months that they were given the flaxseed.
While Hendrich admits that's considerably less than the expected outcome from cholesterol-lowering drugs -- approximately 10 to20 percent for three months, depending on the individual -- it's still enough to make flaxseed a more natural option for some men.
"Because there are people who can't take something like Lipitor, this could at least give you some of that cholesterol-lowering benefit," Hendrich said. "The other thing is, there are certainly some people who would prefer to not use a drug, but rather use foods to try to maintain their health. So this potentially would be something to consider."
Americans suffer from high blood cholesterol
According to the Centers for Disease Control and Prevention, about 17 percent of Americans suffer from high blood cholesterol -- a fat-like substance found in the body that can clog arteries and contribute to heart disease.
Hendrich developed the study with ISU master's student Kai Ling Kong and doctoral graduates Zhong Ye, Xianai Wu, and Sun-Ok Lee to determine whether the main lignan in flaxseed, secoisolariciresinol diglucoside, could lower cholesterol.
The study's 90 subjects -- which included twice as many men as women -- all had high cholesterol, but no other underlying health conditions. The participants were divided into three groups and were randomly assigned to daily consume tablets that contained zero, 150, or 300 milligrams of flaxseed lignans for 12 weeks.
It's the flaxseed lignans -- a group of chemical compounds found in plants that are known for their protective health effects -- that may help lower cholesterol, according to Hendrich. These compounds are converted to their bioactive forms by gut microbes. Hendrich reports that they made a healthy conversion in the subjects in this study, with no adverse health consequences.
No cholesterol-lowering effect in women
While the study found that the flaxseed lignans lowered cholesterol in men, it did not produce a significant change in women.
"We're really puzzled about that because we were looking at post menopausal women and these lignans are known as plant estrogens, so they have a very weak but measurable estrogen effect," Hendrich said. "So potentially, they would have a mild effect for substituting some estrogens in women. It's really hard to know why [there was no effect in women] and whether these substances are counteracting, possibly, some testosterone in men, which of course women don't have. It's definitely something we'd like to investigate further."
Hendrich reports the flaxseed lignan tablets used in this study are not currently available in the U.S. to her knowledge. In the absence of tablets, she says flaxseed can also be sprinkled on cereal, or added in a muffin mix or bread, although whole seeds are not very digestible. Ground flaxseed meal can also provide the desired cholesterol-lowering lignans, according to Hendrich, but it will oxidize over time and could potentially affect the flavor of the foods that it's in. She points out that the oxidation of the product also would diminish the flaxseed's omega-3 fatty acids, which can prevent heart attacks, so freshness is important in the product's impact.
-30-
A new study from Iowa State University's Nutrition and Wellness Research Center (NWRC) may give men a way to combat high cholesterol without drugs -- if they don't mind sprinkling some flaxseed into their daily diet.
Suzanne Hendrich, an ISU professor in food science and human nutrition, led a study that examined the effects of flaxseed lignan in 90 people diagnosed with high cholesterol. The results showed that consuming at least 150 milligrams of flaxseed lignans per day (about three tablespoons) decreased cholesterol in men, but not women, by just under 10 percent over the three months that they were given the flaxseed.
While Hendrich admits that's considerably less than the expected outcome from cholesterol-lowering drugs -- approximately 10 to20 percent for three months, depending on the individual -- it's still enough to make flaxseed a more natural option for some men.
"Because there are people who can't take something like Lipitor, this could at least give you some of that cholesterol-lowering benefit," Hendrich said. "The other thing is, there are certainly some people who would prefer to not use a drug, but rather use foods to try to maintain their health. So this potentially would be something to consider."
Americans suffer from high blood cholesterol
According to the Centers for Disease Control and Prevention, about 17 percent of Americans suffer from high blood cholesterol -- a fat-like substance found in the body that can clog arteries and contribute to heart disease.
Hendrich developed the study with ISU master's student Kai Ling Kong and doctoral graduates Zhong Ye, Xianai Wu, and Sun-Ok Lee to determine whether the main lignan in flaxseed, secoisolariciresinol diglucoside, could lower cholesterol.
The study's 90 subjects -- which included twice as many men as women -- all had high cholesterol, but no other underlying health conditions. The participants were divided into three groups and were randomly assigned to daily consume tablets that contained zero, 150, or 300 milligrams of flaxseed lignans for 12 weeks.
It's the flaxseed lignans -- a group of chemical compounds found in plants that are known for their protective health effects -- that may help lower cholesterol, according to Hendrich. These compounds are converted to their bioactive forms by gut microbes. Hendrich reports that they made a healthy conversion in the subjects in this study, with no adverse health consequences.
No cholesterol-lowering effect in women
While the study found that the flaxseed lignans lowered cholesterol in men, it did not produce a significant change in women.
"We're really puzzled about that because we were looking at post menopausal women and these lignans are known as plant estrogens, so they have a very weak but measurable estrogen effect," Hendrich said. "So potentially, they would have a mild effect for substituting some estrogens in women. It's really hard to know why [there was no effect in women] and whether these substances are counteracting, possibly, some testosterone in men, which of course women don't have. It's definitely something we'd like to investigate further."
Hendrich reports the flaxseed lignan tablets used in this study are not currently available in the U.S. to her knowledge. In the absence of tablets, she says flaxseed can also be sprinkled on cereal, or added in a muffin mix or bread, although whole seeds are not very digestible. Ground flaxseed meal can also provide the desired cholesterol-lowering lignans, according to Hendrich, but it will oxidize over time and could potentially affect the flavor of the foods that it's in. She points out that the oxidation of the product also would diminish the flaxseed's omega-3 fatty acids, which can prevent heart attacks, so freshness is important in the product's impact.
-30-
Soy Isoflavones Fail to Prevent Bone Loss
Researchers supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) provided convincing evidence questioning the notion that soy isoflavone tablets can help preserve bone mineral density (BMD) in women after menopause. Their study, the longest ever to evaluate the effect of soy isoflavones on BMD, appeared recently in the American Journal of Clinical Nutrition.
Isoflavones are naturally occurring compounds found in soybeans. Because they are structurally similar to estrogen, researchers have thought that they may hold promise as an alternative to estrogen therapy to protect postmenopausal women from osteoporosis. Several studies have explored the effects of soy isoflavones on bone health, but results have been mixed, ranging from a modest impact to no effect. Most of these studies had various limitations, including their short duration and small sample size, making it difficult to fully evaluate the impact of these compounds on bone health.
Building on lessons learned from earlier studies, Iowa State University’s D. Lee Alekel, Ph.D., and her colleagues at the USDA Agricultural Research Service’s Western Human Nutrition Research Center, conducted the Soy Isoflavones for Reducing Bone Loss (SIRBL) Study, enrolling more than 250 healthy postmenopausal women in this multi-center trial. The women, none of whom had osteoporosis, were randomly assigned to receive one of two doses daily of isoflavones (80 or 120 mg) or a placebo. All of the women received calcium (500 mg) and vitamin D (600 IU) supplements daily.
During three years, women in the isoflavone and placebo groups experienced similar losses in spine, total hip, and whole body BMD. Although women in the 120 mg soy isoflavone group experienced slightly less bone loss in the femoral neck region of the hip, researchers point out that this effect was very modest, particularly given that whole-body fat mass, age, and bone resorption (removal) exerted an overriding effect on bone loss.
This study is part of an emerging body of evidence that refutes a bone-sparing effect of soy isoflavone tablets. And, while researchers did not identify negative effects in soy users, the commonly held, but incorrect public view that soy isoflavones are bone-protective in healthy American women is seriously called into question.
Isoflavones are naturally occurring compounds found in soybeans. Because they are structurally similar to estrogen, researchers have thought that they may hold promise as an alternative to estrogen therapy to protect postmenopausal women from osteoporosis. Several studies have explored the effects of soy isoflavones on bone health, but results have been mixed, ranging from a modest impact to no effect. Most of these studies had various limitations, including their short duration and small sample size, making it difficult to fully evaluate the impact of these compounds on bone health.
Building on lessons learned from earlier studies, Iowa State University’s D. Lee Alekel, Ph.D., and her colleagues at the USDA Agricultural Research Service’s Western Human Nutrition Research Center, conducted the Soy Isoflavones for Reducing Bone Loss (SIRBL) Study, enrolling more than 250 healthy postmenopausal women in this multi-center trial. The women, none of whom had osteoporosis, were randomly assigned to receive one of two doses daily of isoflavones (80 or 120 mg) or a placebo. All of the women received calcium (500 mg) and vitamin D (600 IU) supplements daily.
During three years, women in the isoflavone and placebo groups experienced similar losses in spine, total hip, and whole body BMD. Although women in the 120 mg soy isoflavone group experienced slightly less bone loss in the femoral neck region of the hip, researchers point out that this effect was very modest, particularly given that whole-body fat mass, age, and bone resorption (removal) exerted an overriding effect on bone loss.
This study is part of an emerging body of evidence that refutes a bone-sparing effect of soy isoflavone tablets. And, while researchers did not identify negative effects in soy users, the commonly held, but incorrect public view that soy isoflavones are bone-protective in healthy American women is seriously called into question.
Wednesday, March 24, 2010
Curcumin Fights Liver Damage
*
Curcumin, one of the principal components of the Indian spice turmeric, seems to delay the liver damage that eventually causes cirrhosis, suggests preliminary experimental research in the journal Gut.
Curcumin, which gives turmeric its bright yellow pigment, has long been used in Indian Ayurvedic medicine to treat a wide range of gastrointestinal disorders.
Previous research has indicated that it has anti-inflammatory and antioxidant properties which may be helpful in combating disease.
The research team wanted to find out if curcumin could delay the damage caused by progressive inflammatory conditions of the liver, including primary sclerosing cholangitis and primary biliary cirrhosis.
Both of these conditions, which can be sparked by genetic faults or autoimmune disease, cause the liver's plumbing system of bile ducts to become inflamed, scarred, and blocked. This leads to extensive tissue damage and irreversible and ultimately fatal liver cirrhosis.
The research team analysed tissue and blood samples from mice with chronic liver inflammation before and after adding curcumin to their diet for a period of four and a period of eight weeks.
The results were compared with the equivalent samples from mice with the same condition, but not fed curcumin.
The findings showed that the curcumin diet significantly reduced bile duct blockage and curbed liver cell (hepatocyte) damage and scarring (fibrosis) by interfering with several chemical signalling pathways involved in the inflammatory process.
These effects were clear at both four and eight weeks. No such effects were seen in mice fed a normal diet.
The authors point out that current treatment for inflammatory liver disease involves ursodeoxycholic acid, the long term effects of which remain unclear. The other alternative is a liver transplant.
Curcumin is a natural product, they say, which seems to target several different parts of the inflammatory process, and as such, may therefore offer a very promising treatment in the future.
Curcumin, one of the principal components of the Indian spice turmeric, seems to delay the liver damage that eventually causes cirrhosis, suggests preliminary experimental research in the journal Gut.
Curcumin, which gives turmeric its bright yellow pigment, has long been used in Indian Ayurvedic medicine to treat a wide range of gastrointestinal disorders.
Previous research has indicated that it has anti-inflammatory and antioxidant properties which may be helpful in combating disease.
The research team wanted to find out if curcumin could delay the damage caused by progressive inflammatory conditions of the liver, including primary sclerosing cholangitis and primary biliary cirrhosis.
Both of these conditions, which can be sparked by genetic faults or autoimmune disease, cause the liver's plumbing system of bile ducts to become inflamed, scarred, and blocked. This leads to extensive tissue damage and irreversible and ultimately fatal liver cirrhosis.
The research team analysed tissue and blood samples from mice with chronic liver inflammation before and after adding curcumin to their diet for a period of four and a period of eight weeks.
The results were compared with the equivalent samples from mice with the same condition, but not fed curcumin.
The findings showed that the curcumin diet significantly reduced bile duct blockage and curbed liver cell (hepatocyte) damage and scarring (fibrosis) by interfering with several chemical signalling pathways involved in the inflammatory process.
These effects were clear at both four and eight weeks. No such effects were seen in mice fed a normal diet.
The authors point out that current treatment for inflammatory liver disease involves ursodeoxycholic acid, the long term effects of which remain unclear. The other alternative is a liver transplant.
Curcumin is a natural product, they say, which seems to target several different parts of the inflammatory process, and as such, may therefore offer a very promising treatment in the future.
Tuesday, March 23, 2010
Alcohol in moderation is good for sick hearts too
*
A study by the Catholic University of Campobasso, Italy, shows that a regular and moderate alcohol consumption is beneficial for people who had a previous heart attack or other ischemic vascular events
It was still an open question in medicine. Whereas scientific research has shown beneficial effects of moderate alcohol consumption in healthy people, it was not clear whether this could be valid also for patients who already had heart attack, stroke or another ischemic vascular event. A positive answer comes now from a study performed by the Research Laboratories at the Catholic University of Campobasso, Italy: moderate consumption, defined as one or two glasses of wine a day or the equivalent amounts of beer or other alcoholic beverages, significantly reduces the risk of death from any cause in those who already suffered from ischemic vascular disease.
The research, published in the Journal of the American College of Cardiology (JACC), was performed using the statistic procedure of meta-analysis which allows to combine different studies conducted worldwide to achieve more precise results. Researchers analyzed the most important scientific studies performed during the last years. Eight in total in four Countries: United States, Sweden, Japan and Great Britain. Each study took into account patients already affected by an ischemic vascular event. During the years following the disease onset, patients were followed by researchers to know which were the lifestyle habits, including alcohol consumption, able to avoid a new clinical event. The meta-analysis allowed to pool all those studies for a total of 16,351 people examined.
"We observed – says Simona Costanzo, epidemiologist and first author of the study – that regular and moderate consumption has beneficial effects even for people already affected by heart attack, or stroke. Not only they are less likely to be affected by similar diseases again, but all-cause mortality too resulted to be lower than in those who did not consume any alcoholic beverage".
The effect is very similar to that observed in healthy people. "Risk reduction - Costanzo argues - is about 20%. This means that one event out of five can be spared. It is a huge advantage, comparable to the one already recorded for healthy individuals".
"Studied by our research group for a long time – says Augusto Di Castelnuovo, Head of the Statistic Unit at the Research Laboratories of the Catholic University in Campobasso and co-author of the study - the beneficial effects of moderate alcohol consumption in healthy people are well established. Now we have reason to believe that alcoholic beverages work by the same protective mechanisms also for people already affected by ischemic vascular diseases".
But, as all researches state, the key word is moderation. "When we talk about moderate alcohol consumption, we mean something quite far from what we use to see in TV fictions – says Licia Iacoviello, Head of the Laboratory of Environmental and Genetic Epidemiology and responsible of the Moli-sani Project – We refer to moderation as drinking regularly, at low doses, within a healthy lifestyle, such as the Mediterranean diet. A glass of wine or beer during meals has always been an integral part of the Mediterranean way of eating. Our research highlights another crucial issue: drinking has not only to be moderate, but also regular. A moderate consumption spread along the week is positive. The same amount of weekly alcohol, concentrated in a couple of days is definitely harmful".
"Despite these new positive results- argues Giovanni de Gaetano, Director of the Research Laboratories - we do believe that teetotallers, either healthy or ill, should not start drinking with the aim to earn more health. Our study, as those conducted by our group in the past, is not a kind of invitation to start drinking, but the recognition of a particular lifestyle. This time we need to be cautious since we deal with sick people. We recommend to them to discuss with their own doctor the best choice in terms of alcoholic beverage consumption".
A study by the Catholic University of Campobasso, Italy, shows that a regular and moderate alcohol consumption is beneficial for people who had a previous heart attack or other ischemic vascular events
It was still an open question in medicine. Whereas scientific research has shown beneficial effects of moderate alcohol consumption in healthy people, it was not clear whether this could be valid also for patients who already had heart attack, stroke or another ischemic vascular event. A positive answer comes now from a study performed by the Research Laboratories at the Catholic University of Campobasso, Italy: moderate consumption, defined as one or two glasses of wine a day or the equivalent amounts of beer or other alcoholic beverages, significantly reduces the risk of death from any cause in those who already suffered from ischemic vascular disease.
The research, published in the Journal of the American College of Cardiology (JACC), was performed using the statistic procedure of meta-analysis which allows to combine different studies conducted worldwide to achieve more precise results. Researchers analyzed the most important scientific studies performed during the last years. Eight in total in four Countries: United States, Sweden, Japan and Great Britain. Each study took into account patients already affected by an ischemic vascular event. During the years following the disease onset, patients were followed by researchers to know which were the lifestyle habits, including alcohol consumption, able to avoid a new clinical event. The meta-analysis allowed to pool all those studies for a total of 16,351 people examined.
"We observed – says Simona Costanzo, epidemiologist and first author of the study – that regular and moderate consumption has beneficial effects even for people already affected by heart attack, or stroke. Not only they are less likely to be affected by similar diseases again, but all-cause mortality too resulted to be lower than in those who did not consume any alcoholic beverage".
The effect is very similar to that observed in healthy people. "Risk reduction - Costanzo argues - is about 20%. This means that one event out of five can be spared. It is a huge advantage, comparable to the one already recorded for healthy individuals".
"Studied by our research group for a long time – says Augusto Di Castelnuovo, Head of the Statistic Unit at the Research Laboratories of the Catholic University in Campobasso and co-author of the study - the beneficial effects of moderate alcohol consumption in healthy people are well established. Now we have reason to believe that alcoholic beverages work by the same protective mechanisms also for people already affected by ischemic vascular diseases".
But, as all researches state, the key word is moderation. "When we talk about moderate alcohol consumption, we mean something quite far from what we use to see in TV fictions – says Licia Iacoviello, Head of the Laboratory of Environmental and Genetic Epidemiology and responsible of the Moli-sani Project – We refer to moderation as drinking regularly, at low doses, within a healthy lifestyle, such as the Mediterranean diet. A glass of wine or beer during meals has always been an integral part of the Mediterranean way of eating. Our research highlights another crucial issue: drinking has not only to be moderate, but also regular. A moderate consumption spread along the week is positive. The same amount of weekly alcohol, concentrated in a couple of days is definitely harmful".
"Despite these new positive results- argues Giovanni de Gaetano, Director of the Research Laboratories - we do believe that teetotallers, either healthy or ill, should not start drinking with the aim to earn more health. Our study, as those conducted by our group in the past, is not a kind of invitation to start drinking, but the recognition of a particular lifestyle. This time we need to be cautious since we deal with sick people. We recommend to them to discuss with their own doctor the best choice in terms of alcoholic beverage consumption".
Link between sunlight, multiple sclerosis
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For more than 30 years, scientists have known that multiple sclerosis (MS) is much more common in higher latitudes than in the tropics. Because sunlight is more abundant near the equator, many researchers have wondered if the high levels of vitamin D engendered by sunlight could explain this unusual pattern of prevalence.
Vitamin D may reduce the symptoms of MS, says Hector DeLuca, Steenbock Research Professor of Biochemistry at University of Wisconsin-Madison, but in a study published in PNAS this week, he and first author Bryan Becklund suggest that the ultraviolet portion of sunlight may play a bigger role than vitamin D in controlling MS.
Multiple sclerosis is a painful neurological disease caused by a deterioration in the nerve's electrical conduction; an estimated 400,000 people have the disabling condition in the United States. In recent years, it's become clear the patients' immune systems are destroying the electrical insulation on the nerve fibers.
The ultraviolet (UV) portion of sunlight stimulates the body to produce vitamin D, and both vitamin D and UV can regulate the immune system and perhaps slow MS. But does the immune regulation result directly from the UV, indirectly from the creation of vitamin D, or both?
The study was designed to distinguish the role of vitamin D and UV light in explaining the high rate of MS away from the equator, says DeLuca, a world authority on vitamin D.
"Since the 1970s, a lot of people have believed that sunlight worked through vitamin D to reduce MS," says DeLuca. "It's true that large doses of the active form of vitamin D can block the disease in the animal model. That causes an unacceptably high level of calcium in the blood, but we know that people at the equator don't have this high blood calcium, even though they have a low incidence of MS. So it seems that something other than vitamin D could explain this geographic relationship."
Using mice that are genetically susceptible to MS-like disease, the researchers triggered the disease by injecting a protein from nerve fibers. The researchers then exposed the mice to moderate levels of UV radiation for a week. After they initiated disease by injecting the protein, they irradiated the mice every second or third day.
The UV exposure (equivalent to two hours of direct summer sun) did not change how many mice got the MS-like disease, but it did reduce the symptoms of MS, especially in the animals that were treated with UV every other day, DeLuca says.
The research group also found that although the UV exposure did increase the level of vitamin D, that effect, by itself, could not explain the reduced MS symptoms.
In some situations, radiation does reduce immune reactions, but it's not clear what role that might play in the current study. "We are looking to identify what compounds are produced in the skin that might play a role, but we honestly don't know what is going on," DeLuca says. "Somehow it makes the animal either tolerate what's going on, or have some reactive mechanism that blocks the autoimmune damage."
MS is a progressive neurological disease with few effective treatments, but DeLuca stresses that the study, however hopeful, may or may not lead to a new mode of treatment. "There are several ways this could go. If we can find out what the UV is producing, maybe we could give that as a medicine. In the short term, if we can define a specific wavelength of light that is active, and it does not overlap with the wavelengths that cause cancer, we could expose patients who have been diagnosed with MS to that wavelength."
Does this information change the common prescription to avoid excessive sun exposure? "If you have an early bout with MS, then you have to think about your options," says DeLuca. "Remember, this is just experimental work at this stage. Whether it can be translated into practical applications on MS remains to be seen."
For more than 30 years, scientists have known that multiple sclerosis (MS) is much more common in higher latitudes than in the tropics. Because sunlight is more abundant near the equator, many researchers have wondered if the high levels of vitamin D engendered by sunlight could explain this unusual pattern of prevalence.
Vitamin D may reduce the symptoms of MS, says Hector DeLuca, Steenbock Research Professor of Biochemistry at University of Wisconsin-Madison, but in a study published in PNAS this week, he and first author Bryan Becklund suggest that the ultraviolet portion of sunlight may play a bigger role than vitamin D in controlling MS.
Multiple sclerosis is a painful neurological disease caused by a deterioration in the nerve's electrical conduction; an estimated 400,000 people have the disabling condition in the United States. In recent years, it's become clear the patients' immune systems are destroying the electrical insulation on the nerve fibers.
The ultraviolet (UV) portion of sunlight stimulates the body to produce vitamin D, and both vitamin D and UV can regulate the immune system and perhaps slow MS. But does the immune regulation result directly from the UV, indirectly from the creation of vitamin D, or both?
The study was designed to distinguish the role of vitamin D and UV light in explaining the high rate of MS away from the equator, says DeLuca, a world authority on vitamin D.
"Since the 1970s, a lot of people have believed that sunlight worked through vitamin D to reduce MS," says DeLuca. "It's true that large doses of the active form of vitamin D can block the disease in the animal model. That causes an unacceptably high level of calcium in the blood, but we know that people at the equator don't have this high blood calcium, even though they have a low incidence of MS. So it seems that something other than vitamin D could explain this geographic relationship."
Using mice that are genetically susceptible to MS-like disease, the researchers triggered the disease by injecting a protein from nerve fibers. The researchers then exposed the mice to moderate levels of UV radiation for a week. After they initiated disease by injecting the protein, they irradiated the mice every second or third day.
The UV exposure (equivalent to two hours of direct summer sun) did not change how many mice got the MS-like disease, but it did reduce the symptoms of MS, especially in the animals that were treated with UV every other day, DeLuca says.
The research group also found that although the UV exposure did increase the level of vitamin D, that effect, by itself, could not explain the reduced MS symptoms.
In some situations, radiation does reduce immune reactions, but it's not clear what role that might play in the current study. "We are looking to identify what compounds are produced in the skin that might play a role, but we honestly don't know what is going on," DeLuca says. "Somehow it makes the animal either tolerate what's going on, or have some reactive mechanism that blocks the autoimmune damage."
MS is a progressive neurological disease with few effective treatments, but DeLuca stresses that the study, however hopeful, may or may not lead to a new mode of treatment. "There are several ways this could go. If we can find out what the UV is producing, maybe we could give that as a medicine. In the short term, if we can define a specific wavelength of light that is active, and it does not overlap with the wavelengths that cause cancer, we could expose patients who have been diagnosed with MS to that wavelength."
Does this information change the common prescription to avoid excessive sun exposure? "If you have an early bout with MS, then you have to think about your options," says DeLuca. "Remember, this is just experimental work at this stage. Whether it can be translated into practical applications on MS remains to be seen."
Walnuts good for the heart & prostate
Walnuts slow prostate tumors in mice
UC Davis research shows walnuts affect genes related to tumor growth
(SACRAMENTO, Calif.) — Walnut consumption slows the growth of prostate cancer in mice and has beneficial effects on multiple genes related to the control of tumor growth and metabolism, UC Davis and the U.S. Department of Agriculture Western Regional Research Center in Albany, Calif. have found.
The study, by Paul Davis, nutritionist in the Department of Nutrition and a researcher with the UC Davis Cancer Center, announced the findings today at the annual national meeting of the American Chemical Society in San Francisco.
Davis said the research findings provide additional evidence that walnuts, although high in fat, are healthful.
"This study shows that when mice with prostate tumors consume an amount of walnuts that could easily be eaten by a man, tumor growth is controlled," he said. "This leaves me very hopeful that it could be beneficial in patients."
Prostate cancer affects one in six American men. It is one in which environmental factors, especially diet, play an important role. Numerous clinical studies have demonstrated that eating walnuts -- rich in omega-3 polyunsaturated fats, antioxidants and other plant chemicals -- decreases the risk of cardiovascular disease. These findings prompted the U.S. Food & Drug Administration in 2004 to approve, for the first time, a qualified health claim for reducing heart disease risk for a whole food.
Davis fed a diet with whole walnuts to mice that had been genetically programmed to get prostate cancer. After 18 weeks, they found that consuming the human equivalent of 2.4 ounces of walnuts per day resulted in significantly smaller, slower-growing prostate tumors compared to mice consuming the same diet with an equal amount of fat, but not from walnuts. They also found that not only was prostate cancer growth reduced by 30 to 40 percent, but that the mice had lower blood levels of a particular protein, insulin-like growth factor (IGF-1), which has been strongly associated with prostate cancer. Additionally, Davis and his research colleagues looked at the effect of walnuts on gene activity in the prostate tumors using whole mouse gene chip technology, and found beneficial effects on multiple genes related to controlling tumor growth and metabolism.
"This is another exciting study from UC Davis nutrition researchers, where truly promising results that have a molecular footprint are having beneficial effects against cancer," said Ralph deVere White, UC Davis Cancer Center director and a prostate cancer researcher. "We have to find a way to get these kinds of studies on nutritional products funded so that we can truly evaluate their effects on cancer patients."
Davis, whose research was funded by a grant to UC Davis from the California Walnut Board, said additional research is needed to further explore how walnuts reduce tumor cell growth.
"The bottom line is that what is good for the heart -- walnuts -- may be good for the prostate as well," he said.
UC Davis research shows walnuts affect genes related to tumor growth
(SACRAMENTO, Calif.) — Walnut consumption slows the growth of prostate cancer in mice and has beneficial effects on multiple genes related to the control of tumor growth and metabolism, UC Davis and the U.S. Department of Agriculture Western Regional Research Center in Albany, Calif. have found.
The study, by Paul Davis, nutritionist in the Department of Nutrition and a researcher with the UC Davis Cancer Center, announced the findings today at the annual national meeting of the American Chemical Society in San Francisco.
Davis said the research findings provide additional evidence that walnuts, although high in fat, are healthful.
"This study shows that when mice with prostate tumors consume an amount of walnuts that could easily be eaten by a man, tumor growth is controlled," he said. "This leaves me very hopeful that it could be beneficial in patients."
Prostate cancer affects one in six American men. It is one in which environmental factors, especially diet, play an important role. Numerous clinical studies have demonstrated that eating walnuts -- rich in omega-3 polyunsaturated fats, antioxidants and other plant chemicals -- decreases the risk of cardiovascular disease. These findings prompted the U.S. Food & Drug Administration in 2004 to approve, for the first time, a qualified health claim for reducing heart disease risk for a whole food.
Davis fed a diet with whole walnuts to mice that had been genetically programmed to get prostate cancer. After 18 weeks, they found that consuming the human equivalent of 2.4 ounces of walnuts per day resulted in significantly smaller, slower-growing prostate tumors compared to mice consuming the same diet with an equal amount of fat, but not from walnuts. They also found that not only was prostate cancer growth reduced by 30 to 40 percent, but that the mice had lower blood levels of a particular protein, insulin-like growth factor (IGF-1), which has been strongly associated with prostate cancer. Additionally, Davis and his research colleagues looked at the effect of walnuts on gene activity in the prostate tumors using whole mouse gene chip technology, and found beneficial effects on multiple genes related to controlling tumor growth and metabolism.
"This is another exciting study from UC Davis nutrition researchers, where truly promising results that have a molecular footprint are having beneficial effects against cancer," said Ralph deVere White, UC Davis Cancer Center director and a prostate cancer researcher. "We have to find a way to get these kinds of studies on nutritional products funded so that we can truly evaluate their effects on cancer patients."
Davis, whose research was funded by a grant to UC Davis from the California Walnut Board, said additional research is needed to further explore how walnuts reduce tumor cell growth.
"The bottom line is that what is good for the heart -- walnuts -- may be good for the prostate as well," he said.
Aspirin use lowers breast & ovarian cancer risk
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Postmenopausal women who regularly use aspirin and other analgesics (known as painkillers) have lower estrogen levels, which could contribute to a decreased risk of breast or ovarian cancer.
"We observed some significant inverse associations between concentrations of several estrogens and the use of aspirin, aspirin plus non-aspirin nonsteroidal anti-inflammatory drugs (NSAIDs), and all analgesics combined," said Margaret A. Gates, Sc.D., research fellow at the Channing Laboratory at Brigham and Women's Hospital and Harvard Medical School.
"Our results suggest that among postmenopausal women, regular users of aspirin and other analgesics may have lower estrogen levels than non-users," Gates added.
These study results are published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
Gates and colleagues examined the association between use of aspirin, NSAIDs and acetaminophen and concentrations of estrogens and androgens among 740 postmenopausal women who participated in the Nurses' Health Study.
Frequency of all analgesic use was inversely associated with estradiol, free estradiol, estrone sulfate and the ratio of estradiol to testosterone.
Average estradiol levels were 10.5 percent lower among women who regularly used aspirin or non-aspirin NSAIDs. Similarly, free estradiol levels were 10.6 percent lower and estrone sulfate levels were 11.1 percent lower among regular users of aspirin or other NSAIDs. Among regular users of any analgesic (aspirin, NSAIDs or acetaminophen), levels of these hormones were 15.2 percent, 12.9 percent and 12.6 percent lower, respectively, according to Gates.
Michael J. Thun, M.D., M.S., vice president emeritus of epidemiology and surveillance research at the American Cancer Society, said the question of whether regular use of aspirin and other NSAIDs is causally related to reduced breast cancer risk is important, but still unresolved.
Thun believes these study results do not confirm whether aspirin-like drugs caused the reduction in circulating estradiol. However, the results do provide evidence that aspirin and other NSAIDs might reduce circulating levels of estradiol by about 10 percent, according to Thun, who is an editorial board member of Cancer Epidemiology, Biomarkers & Prevention, and was not associated with this study.
"Hopefully these findings will motivate a trial to determine whether the association between aspirin use and hormone levels is causal," he said. "Until then, we have a possible mechanism for a potentially important, but as yet unproven chemopreventive benefit."
Gates agreed and said that additional research, like a randomized trial of NSAID use and hormone levels, is needed to confirm these results and to determine whether the decrease in hormone levels translates to a reduced risk of breast or ovarian cancer. If an inverse association between analgesic use and risk of breast or ovarian cancer is confirmed, then this research may have important public health implications.
"Although the overall risks and benefits would need to be weighed, analgesics could be implemented as a chemopreventive and may decrease the risk of several cancers," she said.
Postmenopausal women who regularly use aspirin and other analgesics (known as painkillers) have lower estrogen levels, which could contribute to a decreased risk of breast or ovarian cancer.
"We observed some significant inverse associations between concentrations of several estrogens and the use of aspirin, aspirin plus non-aspirin nonsteroidal anti-inflammatory drugs (NSAIDs), and all analgesics combined," said Margaret A. Gates, Sc.D., research fellow at the Channing Laboratory at Brigham and Women's Hospital and Harvard Medical School.
"Our results suggest that among postmenopausal women, regular users of aspirin and other analgesics may have lower estrogen levels than non-users," Gates added.
These study results are published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.
Gates and colleagues examined the association between use of aspirin, NSAIDs and acetaminophen and concentrations of estrogens and androgens among 740 postmenopausal women who participated in the Nurses' Health Study.
Frequency of all analgesic use was inversely associated with estradiol, free estradiol, estrone sulfate and the ratio of estradiol to testosterone.
Average estradiol levels were 10.5 percent lower among women who regularly used aspirin or non-aspirin NSAIDs. Similarly, free estradiol levels were 10.6 percent lower and estrone sulfate levels were 11.1 percent lower among regular users of aspirin or other NSAIDs. Among regular users of any analgesic (aspirin, NSAIDs or acetaminophen), levels of these hormones were 15.2 percent, 12.9 percent and 12.6 percent lower, respectively, according to Gates.
Michael J. Thun, M.D., M.S., vice president emeritus of epidemiology and surveillance research at the American Cancer Society, said the question of whether regular use of aspirin and other NSAIDs is causally related to reduced breast cancer risk is important, but still unresolved.
Thun believes these study results do not confirm whether aspirin-like drugs caused the reduction in circulating estradiol. However, the results do provide evidence that aspirin and other NSAIDs might reduce circulating levels of estradiol by about 10 percent, according to Thun, who is an editorial board member of Cancer Epidemiology, Biomarkers & Prevention, and was not associated with this study.
"Hopefully these findings will motivate a trial to determine whether the association between aspirin use and hormone levels is causal," he said. "Until then, we have a possible mechanism for a potentially important, but as yet unproven chemopreventive benefit."
Gates agreed and said that additional research, like a randomized trial of NSAID use and hormone levels, is needed to confirm these results and to determine whether the decrease in hormone levels translates to a reduced risk of breast or ovarian cancer. If an inverse association between analgesic use and risk of breast or ovarian cancer is confirmed, then this research may have important public health implications.
"Although the overall risks and benefits would need to be weighed, analgesics could be implemented as a chemopreventive and may decrease the risk of several cancers," she said.
Optimism Boosts the Immune System
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Feeling better about the future might help you feel better for real. In a new study, psychological scientists Suzanne Segerstrom of the University of Kentucky and Sandra Sephton of the University of Louisville studied how law students' expectations about the future affected their immune response. Their conclusions: Optimism may be good for your health.
Other studies have found that people who are optimistic about their health tend to do better. For example, people who are optimistic about heart transplant surgery recover better from that grueling operation. But it's not clear how optimism affects your health — or whether pessimism makes you less healthy.
For this study, reported in Psychological Science, a journal of the Association for Psychological Science, the researchers recruited first-year law students by sending them a packet during the summer before classes started. The 124 students that participated in the research were studied at five times over six months. Each time, they answered questions about how optimistic they felt about law school. Then they were injected with material that should summon an immune response and two days later, they came back to have the injection site measured. A larger bump in the skin means a stronger immune response. Immune systems are many-faceted; this test only measures the strength of the part that is responsible for fighting viral infections and some bacterial infections.
The students' general outlook on life — whether they had an optimistic disposition — didn't account for the differences in immune responses between students. But as each student's expectations about law school waxed and waned, their immune response followed along. At more optimistic times, they'd have bigger immune responses; at a more pessimistic time, a more sluggish immune response. So, being optimistic about success in a specific, important domain may promote better immunity against some infections.
Of course, the law students often have good reason to be optimistic or pessimistic; by a few months into the first semester, they've gotten some grades back and started to figure out if they're good or bad at law school. "I don't think that I would advise people that they should revise their expectations to be unrealistic," says Segerstrom. "But if people have slightly more positive views of the future than is actually true, that's adaptive."
Feeling better about the future might help you feel better for real. In a new study, psychological scientists Suzanne Segerstrom of the University of Kentucky and Sandra Sephton of the University of Louisville studied how law students' expectations about the future affected their immune response. Their conclusions: Optimism may be good for your health.
Other studies have found that people who are optimistic about their health tend to do better. For example, people who are optimistic about heart transplant surgery recover better from that grueling operation. But it's not clear how optimism affects your health — or whether pessimism makes you less healthy.
For this study, reported in Psychological Science, a journal of the Association for Psychological Science, the researchers recruited first-year law students by sending them a packet during the summer before classes started. The 124 students that participated in the research were studied at five times over six months. Each time, they answered questions about how optimistic they felt about law school. Then they were injected with material that should summon an immune response and two days later, they came back to have the injection site measured. A larger bump in the skin means a stronger immune response. Immune systems are many-faceted; this test only measures the strength of the part that is responsible for fighting viral infections and some bacterial infections.
The students' general outlook on life — whether they had an optimistic disposition — didn't account for the differences in immune responses between students. But as each student's expectations about law school waxed and waned, their immune response followed along. At more optimistic times, they'd have bigger immune responses; at a more pessimistic time, a more sluggish immune response. So, being optimistic about success in a specific, important domain may promote better immunity against some infections.
Of course, the law students often have good reason to be optimistic or pessimistic; by a few months into the first semester, they've gotten some grades back and started to figure out if they're good or bad at law school. "I don't think that I would advise people that they should revise their expectations to be unrealistic," says Segerstrom. "But if people have slightly more positive views of the future than is actually true, that's adaptive."
Spice Up Your Health This Barbecue Season
A new study at The University of Western Ontario finds the sauces you use when firing up the barbecue this summer may provide unforeseen health benefits.
The research, led by Western biology and psychology postdoctoral fellow Raymond Thomas, shows common marinades may be more than just tasty sauces – they can also provide a major source of natural antioxidants. The paper was co-authored by Mark Bernards and Christopher Guglielmo in Western’s department of biology.
Foods rich in antioxidants play an essential role in preventing cardiovascular diseases, cancers, neurodegenerative diseases like Alzheimer’s and Parkinson’s, inflammation and problems associated with cutaneous aging.
“Herbs and spices are excellent sources of antioxidants, but estimating consumption rates can be difficult considering they are not generally consumed in large quantities, compared to fruits and vegetables,” says Thomas. “Instead, they are used in relatively small amounts as ingredients in recipes and formulations such as spice mixes and marinating sauces that enhance food flavour.”
Diverse processing methods during manufacture, length of marinating time and exposure to various modes of cooking can significantly alter the antioxidant status of these products and, consequently, the amount of antioxidants available to consumers.
Thomas was able to show for the first time the impact of marinating and cooking meat on the antioxidant status of seven different popular brands and flavours of marinade containing herbs and spices as primary ingredients. Each is readily available at local grocery stores and included jerk sauce, garlic and herb, honey garlic, roasted red pepper, lemon pepper garlic, sesame ginger teriyaki and green seasoning.
His research found very good quantities of antioxidants in all seven sauces, but that marinating meat prior to cooking reduced antioxidant levels by 45-70 percent. Both Grace Jerk Sauce and Renée’s Sesame Ginger Teriyaki outperformed the other five sauces tested before and after cooking because they contain substantial quantities of ingredients like hot peppers, allspice, sesame and ginger – all of which have high antioxidant properties.
Despite the high percentage of antioxidant loss following marinating and cooking, the sauces still provide benefits over cooking meat without them.
“Consumers can maximize their intake of the antioxidants available in these sauces by choosing those with the highest antioxidant levels prior to marinating and cooking,” says Thomas. “Alternatively, you can brush the sauce on just before serving the meat, or consume it without cooking – like as a salad dressing – where it is permissible to do so.”
The research, led by Western biology and psychology postdoctoral fellow Raymond Thomas, shows common marinades may be more than just tasty sauces – they can also provide a major source of natural antioxidants. The paper was co-authored by Mark Bernards and Christopher Guglielmo in Western’s department of biology.
Foods rich in antioxidants play an essential role in preventing cardiovascular diseases, cancers, neurodegenerative diseases like Alzheimer’s and Parkinson’s, inflammation and problems associated with cutaneous aging.
“Herbs and spices are excellent sources of antioxidants, but estimating consumption rates can be difficult considering they are not generally consumed in large quantities, compared to fruits and vegetables,” says Thomas. “Instead, they are used in relatively small amounts as ingredients in recipes and formulations such as spice mixes and marinating sauces that enhance food flavour.”
Diverse processing methods during manufacture, length of marinating time and exposure to various modes of cooking can significantly alter the antioxidant status of these products and, consequently, the amount of antioxidants available to consumers.
Thomas was able to show for the first time the impact of marinating and cooking meat on the antioxidant status of seven different popular brands and flavours of marinade containing herbs and spices as primary ingredients. Each is readily available at local grocery stores and included jerk sauce, garlic and herb, honey garlic, roasted red pepper, lemon pepper garlic, sesame ginger teriyaki and green seasoning.
His research found very good quantities of antioxidants in all seven sauces, but that marinating meat prior to cooking reduced antioxidant levels by 45-70 percent. Both Grace Jerk Sauce and Renée’s Sesame Ginger Teriyaki outperformed the other five sauces tested before and after cooking because they contain substantial quantities of ingredients like hot peppers, allspice, sesame and ginger – all of which have high antioxidant properties.
Despite the high percentage of antioxidant loss following marinating and cooking, the sauces still provide benefits over cooking meat without them.
“Consumers can maximize their intake of the antioxidants available in these sauces by choosing those with the highest antioxidant levels prior to marinating and cooking,” says Thomas. “Alternatively, you can brush the sauce on just before serving the meat, or consume it without cooking – like as a salad dressing – where it is permissible to do so.”
Are Hand Sanitizers Better than Handwashing Against the Common Cold?
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A new study suggests that hand sanitizers containing ethanol are much more effective at removing rhinovirus from hands than washing with soap and water. Sanitizers containing both ethanol and organic acids significantly reduced recovery of the virus from hands and rhinovirus infection up to 4 hours following application. The researchers from the University of Virginia School of Medicine, Charlottesville and Dial Corporation, Scottsdale, Arizona detail their findings in the March 2010 issue of the journal Antimicrobial Agents and Chemotherapy.
Rhinovirus is the known cause of approximately 30 to 35% of common cold cases in adults. Hand-to-hand contact is one of the main avenues of transmission contributing to the spread of rhinovirus infections. In the study researchers compared the effects of hand washing with soap and water and an ethanol-based hand sanitizer by contaminating the fingers of healthy volunteers with rhinovirus and then randomly grouping them and administering one of six hand treatments. The experiments ranged from a control group who had no treatment, several groups who washed their hands for differing amounts of time (some with soap, some without), and several who used varying amounts of hand sanitizer. Results showed that the ethanol hand sanitizer removed approximately 80% of detectable rhinovirus from hands and was much more effective than no treatment, water alone, or soap and water. Soap and water removed rhinovirus from 31% of hands.
Further, researchers added organic acids to the ethanol-based sanitizer and analyzed its ability to provide persistent antiviral activity against rhinovirus following application. Results showed that the sanitizer containing both organic acids and ethanol inactivated the virus on hands and prevented infection 2 to 4 hours following application.
"The ethanol-containing hand disinfectants were significantly more effective than hand washing with water or with soap and water for removal of detectable rhinovirus for the hands in this study," say the researchers. "Furthermore, a formula containing organic acids and ethanol resulted in residual activity that significantly reduced virus recovery from the hands and rhinovirus infection for up to 4 hours after application."
(R.B. Turner, J.L. Fuls, N.D. Rodgers. 2010. Effectiveness of hand sanitizers with and without organic acids for removal of rhinovirus from hands. Antimicrobial Agents and Chemotherapy, 54. 3: 1363-1364.)
A new study suggests that hand sanitizers containing ethanol are much more effective at removing rhinovirus from hands than washing with soap and water. Sanitizers containing both ethanol and organic acids significantly reduced recovery of the virus from hands and rhinovirus infection up to 4 hours following application. The researchers from the University of Virginia School of Medicine, Charlottesville and Dial Corporation, Scottsdale, Arizona detail their findings in the March 2010 issue of the journal Antimicrobial Agents and Chemotherapy.
Rhinovirus is the known cause of approximately 30 to 35% of common cold cases in adults. Hand-to-hand contact is one of the main avenues of transmission contributing to the spread of rhinovirus infections. In the study researchers compared the effects of hand washing with soap and water and an ethanol-based hand sanitizer by contaminating the fingers of healthy volunteers with rhinovirus and then randomly grouping them and administering one of six hand treatments. The experiments ranged from a control group who had no treatment, several groups who washed their hands for differing amounts of time (some with soap, some without), and several who used varying amounts of hand sanitizer. Results showed that the ethanol hand sanitizer removed approximately 80% of detectable rhinovirus from hands and was much more effective than no treatment, water alone, or soap and water. Soap and water removed rhinovirus from 31% of hands.
Further, researchers added organic acids to the ethanol-based sanitizer and analyzed its ability to provide persistent antiviral activity against rhinovirus following application. Results showed that the sanitizer containing both organic acids and ethanol inactivated the virus on hands and prevented infection 2 to 4 hours following application.
"The ethanol-containing hand disinfectants were significantly more effective than hand washing with water or with soap and water for removal of detectable rhinovirus for the hands in this study," say the researchers. "Furthermore, a formula containing organic acids and ethanol resulted in residual activity that significantly reduced virus recovery from the hands and rhinovirus infection for up to 4 hours after application."
(R.B. Turner, J.L. Fuls, N.D. Rodgers. 2010. Effectiveness of hand sanitizers with and without organic acids for removal of rhinovirus from hands. Antimicrobial Agents and Chemotherapy, 54. 3: 1363-1364.)
Good fat cuts heart risk by a fifth, study shows
*
A Harvard Medical School study says for every 5% increase in polyunsaturated fat consumption there was a 10% fall in heart disease.
The reports adds to the growing evidence about polyunsaturated fats, found in some fish and vegetable oils.
The team analyzed the findings from eight previous studies, covering more than 13,000 people, in their research.
Saturated fats raise the levels of bad cholesterol that block the arteries to the heart.
In comparison, polyunsaturated fats have the opposite effect by increasing the levels of good cholesterol.
*
A Harvard Medical School study says for every 5% increase in polyunsaturated fat consumption there was a 10% fall in heart disease.
The reports adds to the growing evidence about polyunsaturated fats, found in some fish and vegetable oils.
The team analyzed the findings from eight previous studies, covering more than 13,000 people, in their research.
Saturated fats raise the levels of bad cholesterol that block the arteries to the heart.
In comparison, polyunsaturated fats have the opposite effect by increasing the levels of good cholesterol.
*
Friday, March 19, 2010
Failed college dreams don't spell depression, study finds
*
High school seniors, take note: A wise person once said, "It is better to shoot for the stars and miss than aim at the gutter and hit it."
That's right on, says Florida State University Sociology Professor John R. Reynolds, who just completed a study to determine whether unrealized educational expectations are associated with depression among adults. Reynolds also is the director of the Pepper Institute on Aging and Public Policy at Florida State.
He and co-author Chardie L. Baird, an assistant professor of sociology at Kansas State University, found no long-term emotional costs of aiming high and falling short when it comes to educational aspirations, despite several social psychological theories that would seem to suggest otherwise. The researchers' conclusion: Society should not discourage unpromising students who have dreams of earning a college degree.
"We should not be in a hurry to dissuade these students from planning to go to college," Reynolds said. "In fact, the only way to guarantee negative mental health outcomes is not trying. Aiming high and failing is not consequential for mental health, while trying may lead to higher achievements and the mental and material benefits that go along with those achievements."
"Is There a Downside to Shooting for the Stars? Unrealized Educational Expectations and Symptoms of Depression," which was published in the American Sociological Review (http://asr.sagepub.com/cgi/content/full/75/1/151), is the first large, national study to look at the mental health consequences of failing to meet educational expectations.
"My previous research showed that teenagers are increasingly unrealistic about what they will be able to achieve," Reynolds said. "I wanted to see if there is anything wrong with that trend. Lots of theories predict that unmet goals will lead to frustration and anxiety. We were very surprised to find out that over-ambition is not a big concern, at least not from a mental health perspective."
Most young people in the United States expect to attend college, earn a four-year degree and work in a professional occupation. Yet the extent to which teenagers' achievement expectations are out of line with what they actually attain is also on the rise.
In a 2006 study, Reynolds and colleagues found that the gap between the percentage of high school seniors expecting to obtain bachelor's degrees and the percentage of young adults with a degree had doubled in the 25-year period between 1976 and 2000. In other words, increases in high school students' college expectations outpaced increases in young adults' achievements, a result they interpret as "ambition inflation."
Several social psychological theories suggest that's a problem, albeit for different reasons. Self-discrepancy theory says that a gap between a person's ideal self and his or her actual self is detrimental to mental health. Another, relative deprivation theory, claims that individuals experience mental distress when they are deprived of a reward or status to which they feel entitled. Social stress theory asserts that "non-events," such as not being married by a certain age or a promotion that never happens, are distressing.
Reynolds and Baird used two national studies of youth, the National Longitudinal Study and the Longitudinal Study of Adolescent Health (ADD Health), both of which track respondents over a period of time, to test whether unrealized expectations are associated with depression in adulthood. Using data from more than 4,300 respondents, they compared the count of symptoms of depression for those who did and did not achieve their earlier educational plans and found little difference.
Those with lower levels of education did have more depression, but the depression was associated with the lower attainment, not any gap between plans and attainment, Reynolds said. Previous research has established that more educated individuals report better mental and physical health.
The researchers theorize that many young adults who did not reach their educational goals develop a sort of "adaptive resilience" that buffers them from the kind of depression that could result from feelings of failure. A dramatic increase in older undergraduates in recent years also suggests that young people do not necessarily believe they must meet their educational goals while still in their 20s.
"It may be that young adults can successfully adapt to the unexpected, focusing on the positive aspects of their transition to adulthood rather than dwelling on plans that have fallen through or have been put on hold indefinitely," Reynolds said. "They might also deal with failed plans by extending the plans forward in time as achievements still to come. Young adults with college expectations may visualize having their entire lives to realize their educational plans."
High school seniors, take note: A wise person once said, "It is better to shoot for the stars and miss than aim at the gutter and hit it."
That's right on, says Florida State University Sociology Professor John R. Reynolds, who just completed a study to determine whether unrealized educational expectations are associated with depression among adults. Reynolds also is the director of the Pepper Institute on Aging and Public Policy at Florida State.
He and co-author Chardie L. Baird, an assistant professor of sociology at Kansas State University, found no long-term emotional costs of aiming high and falling short when it comes to educational aspirations, despite several social psychological theories that would seem to suggest otherwise. The researchers' conclusion: Society should not discourage unpromising students who have dreams of earning a college degree.
"We should not be in a hurry to dissuade these students from planning to go to college," Reynolds said. "In fact, the only way to guarantee negative mental health outcomes is not trying. Aiming high and failing is not consequential for mental health, while trying may lead to higher achievements and the mental and material benefits that go along with those achievements."
"Is There a Downside to Shooting for the Stars? Unrealized Educational Expectations and Symptoms of Depression," which was published in the American Sociological Review (http://asr.sagepub.com/cgi/content/full/75/1/151), is the first large, national study to look at the mental health consequences of failing to meet educational expectations.
"My previous research showed that teenagers are increasingly unrealistic about what they will be able to achieve," Reynolds said. "I wanted to see if there is anything wrong with that trend. Lots of theories predict that unmet goals will lead to frustration and anxiety. We were very surprised to find out that over-ambition is not a big concern, at least not from a mental health perspective."
Most young people in the United States expect to attend college, earn a four-year degree and work in a professional occupation. Yet the extent to which teenagers' achievement expectations are out of line with what they actually attain is also on the rise.
In a 2006 study, Reynolds and colleagues found that the gap between the percentage of high school seniors expecting to obtain bachelor's degrees and the percentage of young adults with a degree had doubled in the 25-year period between 1976 and 2000. In other words, increases in high school students' college expectations outpaced increases in young adults' achievements, a result they interpret as "ambition inflation."
Several social psychological theories suggest that's a problem, albeit for different reasons. Self-discrepancy theory says that a gap between a person's ideal self and his or her actual self is detrimental to mental health. Another, relative deprivation theory, claims that individuals experience mental distress when they are deprived of a reward or status to which they feel entitled. Social stress theory asserts that "non-events," such as not being married by a certain age or a promotion that never happens, are distressing.
Reynolds and Baird used two national studies of youth, the National Longitudinal Study and the Longitudinal Study of Adolescent Health (ADD Health), both of which track respondents over a period of time, to test whether unrealized expectations are associated with depression in adulthood. Using data from more than 4,300 respondents, they compared the count of symptoms of depression for those who did and did not achieve their earlier educational plans and found little difference.
Those with lower levels of education did have more depression, but the depression was associated with the lower attainment, not any gap between plans and attainment, Reynolds said. Previous research has established that more educated individuals report better mental and physical health.
The researchers theorize that many young adults who did not reach their educational goals develop a sort of "adaptive resilience" that buffers them from the kind of depression that could result from feelings of failure. A dramatic increase in older undergraduates in recent years also suggests that young people do not necessarily believe they must meet their educational goals while still in their 20s.
"It may be that young adults can successfully adapt to the unexpected, focusing on the positive aspects of their transition to adulthood rather than dwelling on plans that have fallen through or have been put on hold indefinitely," Reynolds said. "They might also deal with failed plans by extending the plans forward in time as achievements still to come. Young adults with college expectations may visualize having their entire lives to realize their educational plans."
Selenium Protects Men Against Diabetes, Study Suggests
The role of selenium in diabetes has been controversial, with some studies suggesting that it raises diabetes risk and others finding that it is protective. Now, research published in BioMed Central's open access journal Nutrition and Metabolism, has shown that, for men, high plasma selenium concentrations are associated with a lower occurrence of dysglycemia.
Tasnime Akbaraly, from the University of Montpellier, worked with a team of researchers to follow 1162 healthy French men and women for nine years, monitoring plasma selenium concentrations and incidence of dysglycemia.
She said, "Our results showed that for French elderly males, having plasma selenium concentrations in the top tertile of the population distribution (1.19-1.97 μmol/L) was significantly associated with a lower risk of developing dysglycemia over the following nine years."
During the study period, 127 new cases of dysglycemia occurred, of which 70 were in men and 57 in women. According to Akbaraly, "The reason we observed a protective effect of selenium in men but not in women is not completely clear, but might be attributed to women being healthier at baseline, having better antioxidant status in general and possible differences in how men and women process selenium."
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Story Source:
Adapted from materials provided by BioMed Central, via EurekAlert!, a service of AAAS.
Journal Reference:
1. Tasnime N Akbaraly, Josiane Arnaud, Margaret P Rayman, Isabelle Hininger-Favier, Anne-Marie Roussel, Claudine Berr and Annick Fontbonne. Plasma selenium and risk of dysglycemia in an elderly French population: Results from the prospective Epidemiology of Vascular Ageing Study. Nutrition & Metabolism, 2010; (in press) [link]
Need to cite this story in your essay, paper, or report? Use one of the following formats:
APA
MLA
BioMed Central (2010, March 18). Selenium protects men against diabetes, study suggests. ScienceDaily. Retrieved March 19, 2010, from http://www.sciencedaily.com /releases/2010/03/100317212646.htm
Note: If no author is given, the source is cited instead.
Tasnime Akbaraly, from the University of Montpellier, worked with a team of researchers to follow 1162 healthy French men and women for nine years, monitoring plasma selenium concentrations and incidence of dysglycemia.
She said, "Our results showed that for French elderly males, having plasma selenium concentrations in the top tertile of the population distribution (1.19-1.97 μmol/L) was significantly associated with a lower risk of developing dysglycemia over the following nine years."
During the study period, 127 new cases of dysglycemia occurred, of which 70 were in men and 57 in women. According to Akbaraly, "The reason we observed a protective effect of selenium in men but not in women is not completely clear, but might be attributed to women being healthier at baseline, having better antioxidant status in general and possible differences in how men and women process selenium."
Email or share this story:
| More
Story Source:
Adapted from materials provided by BioMed Central, via EurekAlert!, a service of AAAS.
Journal Reference:
1. Tasnime N Akbaraly, Josiane Arnaud, Margaret P Rayman, Isabelle Hininger-Favier, Anne-Marie Roussel, Claudine Berr and Annick Fontbonne. Plasma selenium and risk of dysglycemia in an elderly French population: Results from the prospective Epidemiology of Vascular Ageing Study. Nutrition & Metabolism, 2010; (in press) [link]
Need to cite this story in your essay, paper, or report? Use one of the following formats:
APA
MLA
BioMed Central (2010, March 18). Selenium protects men against diabetes, study suggests. ScienceDaily. Retrieved March 19, 2010, from http://www.sciencedaily.com /releases/2010/03/100317212646.htm
Note: If no author is given, the source is cited instead.
Wednesday, March 17, 2010
Low levels of vitamin D linked to higher rates of asthma in African American Kids
^
Study
Researchers at Children’s National Medical Center have discovered that African American children with asthma in metropolitan Washington, DC, are significantly more likely to have low levels of vitamin D than healthy African American children. This study supports recent research that suggests vitamin D plays a greater role in the body than just keeping bones healthy. Vitamin D deficiency has been recently linked to a variety of non-bone related diseases including depression, autoimmune disorders, and now asthma.
“It’s been well-documented that as a group, African Americans are more likely than other racial groups to have low levels of vitamin D,” said Robert Freishtat, MD, MPH, an emergency medicine physician and lead author on the study. “But we were shocked to see that almost all of the African American children with asthma that we tested had low vitamin D levels. After adjusting for differences in age, weight, and the time of year of the testing, the odds of these kids with asthma being vitamin D deficient were nearly twenty times those of healthy kids.”
The study took a one-time measurement of vitamin D in the blood of 85 African American children with asthma, who were between 6 and 20 years old. Additionally, the researchers measured the vitamin D levels of 21 healthy African American children between the ages of 6 and 9 years of age. The research team found that 86 percent of the children in the study with asthma had insufficient levels of vitamin D, while only 19 percent of non-asthmatics had these low levels.
These findings may mean that low vitamin D levels have more serious effects on a child’s lung health than previously believed. Though more research is needed to establish definitively how vitamin D deficiency can contribute to asthma, parents can ensure that their children receive healthier amounts of vitamin D by following the current USDA guidelines for milk consumption and seeking a doctor’s advice about multivitamins.
“The District of Columbia has among the highest rates of pediatric asthma in the United States, and we’re working to find out why,” says Stephen Teach, MD, MPH, senior author of the study. “For African American kids with asthma, vitamin D testing and ensuring adequate vitamin D intake may need to become necessary steps in their primary care.”
Study
Researchers at Children’s National Medical Center have discovered that African American children with asthma in metropolitan Washington, DC, are significantly more likely to have low levels of vitamin D than healthy African American children. This study supports recent research that suggests vitamin D plays a greater role in the body than just keeping bones healthy. Vitamin D deficiency has been recently linked to a variety of non-bone related diseases including depression, autoimmune disorders, and now asthma.
“It’s been well-documented that as a group, African Americans are more likely than other racial groups to have low levels of vitamin D,” said Robert Freishtat, MD, MPH, an emergency medicine physician and lead author on the study. “But we were shocked to see that almost all of the African American children with asthma that we tested had low vitamin D levels. After adjusting for differences in age, weight, and the time of year of the testing, the odds of these kids with asthma being vitamin D deficient were nearly twenty times those of healthy kids.”
The study took a one-time measurement of vitamin D in the blood of 85 African American children with asthma, who were between 6 and 20 years old. Additionally, the researchers measured the vitamin D levels of 21 healthy African American children between the ages of 6 and 9 years of age. The research team found that 86 percent of the children in the study with asthma had insufficient levels of vitamin D, while only 19 percent of non-asthmatics had these low levels.
These findings may mean that low vitamin D levels have more serious effects on a child’s lung health than previously believed. Though more research is needed to establish definitively how vitamin D deficiency can contribute to asthma, parents can ensure that their children receive healthier amounts of vitamin D by following the current USDA guidelines for milk consumption and seeking a doctor’s advice about multivitamins.
“The District of Columbia has among the highest rates of pediatric asthma in the United States, and we’re working to find out why,” says Stephen Teach, MD, MPH, senior author of the study. “For African American kids with asthma, vitamin D testing and ensuring adequate vitamin D intake may need to become necessary steps in their primary care.”
Tuesday, March 16, 2010
Studies find treating vitamin D deficiency significantly reduces heart disease risk
Preventing and treating heart disease in some patients could be as simple as supplementing their diet with extra vitamin D, according to two new studies
Preventing and treating heart disease in some patients could be as simple as supplementing their diet with extra vitamin D, according to two new studies at the Intermountain Medical Center Heart Institute in Murray, Utah.
Researchers at the Intermountain Medical Center Heart Institute last fall demonstrated the link between vitamin D deficiency and increased risk for coronary artery disease. These new studies show that treating vitamin D deficiency with supplements may help to prevent or reduce a person's risk for cardiovascular disease and a host of other chronic conditions. They also establish what level of vitamin D further enhances that risk reduction.
"Vitamin D replacement therapy has long been associated with reducing the risk of fractures and diseases of the bone," says Dr. J. Brent Muhlestein, MD, director of cardiovascular research at the Intermountain Medical Center Heart Institute. "But our findings show that vitamin D could have far greater implications in the treatment and reduction of cardiovascular disease and other chronic conditions than we previously thought."
For the first study, researchers followed two groups of patients for an average of one year each. In the first study group, over 9,400 patients, mostly female, reported low initial vitamin D levels, and had at least one follow up exam during that time period. Researchers found that 47 percent of the patients who increased their levels of vitamin D between the two visits showed a reduced risk for cardiovascular disease.
In the second study, researchers placed over 31,000 patients into three categories based on their levels of vitamin D. The patients in each category who increased their vitamin D levels to 43 nanograms per milliliter of blood or higher had lower rates of death, diabetes, cardiovascular disease, myocardial infarction, heart failure, high blood pressure, depression, and kidney failure. Currently, a level of 30 nanograms per milliliter is considered "normal."
Heidi May, PhD, a cardiovascular clinical epidemiologist with the Intermountain Medical Center Heart Institute, and one of the study's authors, says the link between low levels of vitamin D and increased risk for a variety of diseases is significant.
"It was very important to discover that the 'normal' levels are too low. Giving physicians a higher level to look for gives them one more tool in identifying patients at-risk and offering them better treatment," says Dr. May.
Dr. Muhlestein says the results of these studies will change the way he treats his patients.
"Although randomized trials would be useful and are coming, I feel there is enough information here for me to start treatment based on these findings," he says.
Treatment options in this case are simple, starting with a blood test to determine a patient's vitamin D level. If low levels are detected, supplements and/or increased exposure to sunlight may be prescribed.
Increasing vitamin D intake by 1000 to 5000 international units (IU) a day may be appropriate, depending on a patient's health and genetic risk, says Dr. Muhlestein. He says supplements are the best source of vitamin D because they are relatively inexpensive and can be found at almost any supermarket or drug store. Most supplements provide an average of 400 IU per tablet.
While exposure to 20-30 minutes of sunlight can provide up to 10,000 IU, Dr. Muhlestein says it is important to use sunscreen and avoid the hottest parts of the day in order to avoid sunburn and the harmful UV rays associated with skin cancer.
Preventing and treating heart disease in some patients could be as simple as supplementing their diet with extra vitamin D, according to two new studies at the Intermountain Medical Center Heart Institute in Murray, Utah.
Researchers at the Intermountain Medical Center Heart Institute last fall demonstrated the link between vitamin D deficiency and increased risk for coronary artery disease. These new studies show that treating vitamin D deficiency with supplements may help to prevent or reduce a person's risk for cardiovascular disease and a host of other chronic conditions. They also establish what level of vitamin D further enhances that risk reduction.
"Vitamin D replacement therapy has long been associated with reducing the risk of fractures and diseases of the bone," says Dr. J. Brent Muhlestein, MD, director of cardiovascular research at the Intermountain Medical Center Heart Institute. "But our findings show that vitamin D could have far greater implications in the treatment and reduction of cardiovascular disease and other chronic conditions than we previously thought."
For the first study, researchers followed two groups of patients for an average of one year each. In the first study group, over 9,400 patients, mostly female, reported low initial vitamin D levels, and had at least one follow up exam during that time period. Researchers found that 47 percent of the patients who increased their levels of vitamin D between the two visits showed a reduced risk for cardiovascular disease.
In the second study, researchers placed over 31,000 patients into three categories based on their levels of vitamin D. The patients in each category who increased their vitamin D levels to 43 nanograms per milliliter of blood or higher had lower rates of death, diabetes, cardiovascular disease, myocardial infarction, heart failure, high blood pressure, depression, and kidney failure. Currently, a level of 30 nanograms per milliliter is considered "normal."
Heidi May, PhD, a cardiovascular clinical epidemiologist with the Intermountain Medical Center Heart Institute, and one of the study's authors, says the link between low levels of vitamin D and increased risk for a variety of diseases is significant.
"It was very important to discover that the 'normal' levels are too low. Giving physicians a higher level to look for gives them one more tool in identifying patients at-risk and offering them better treatment," says Dr. May.
Dr. Muhlestein says the results of these studies will change the way he treats his patients.
"Although randomized trials would be useful and are coming, I feel there is enough information here for me to start treatment based on these findings," he says.
Treatment options in this case are simple, starting with a blood test to determine a patient's vitamin D level. If low levels are detected, supplements and/or increased exposure to sunlight may be prescribed.
Increasing vitamin D intake by 1000 to 5000 international units (IU) a day may be appropriate, depending on a patient's health and genetic risk, says Dr. Muhlestein. He says supplements are the best source of vitamin D because they are relatively inexpensive and can be found at almost any supermarket or drug store. Most supplements provide an average of 400 IU per tablet.
While exposure to 20-30 minutes of sunlight can provide up to 10,000 IU, Dr. Muhlestein says it is important to use sunscreen and avoid the hottest parts of the day in order to avoid sunburn and the harmful UV rays associated with skin cancer.
Vitamin D levels have different effects in blacks and whites
Vitamin D is quickly becoming the "go-to" remedy for treating a wide range of illnesses, from osteoporosis to atherosclerosis. However, new evidence from a Wake Forest University School of Medicine study suggests that supplementing vitamin D in those with low levels may have different effects based on patient race and, in black individuals, the supplement could actually do harm.
The study is the first to show a positive relationship between calcified plaque in large arteries, a measure of atherosclerosis or "hardening of the arteries," and circulating vitamin D levels in black patients. It appears in the March issue of the Journal of Clinical Endocrinology and Metabolism.
"In black patients, lower levels of vitamin D may not signify deficiency to the same extent as in whites," said the study's lead investigator, Barry I. Freedman, M.D., John H. Felts III Professor and chief of the section on nephrology at the School of Medicine "We should use caution when supplementing vitamin D in black patients while we investigate if we are actually worsening calcium deposition in the arteries with treatment."
Vitamin D is widely used to treat patients with osteoporosis and/or low vitamin D levels based on a medically accepted normal range. This "normal" range is typically applied to all race groups, although it was established predominantly in whites. It is thought that as low vitamin D levels rise to the normal range with supplementation, protection from bone and heart disease (atherosclerosis) may increase, as well.
Blacks generally have lower vitamin D levels than whites, partly because their darker skin pigmentation limits the amount of the vitamin produced by sunlight. Blacks also consume fewer dairy products and ingest less dietary calcium than whites, said Freedman, an affiliate of the Maya Angelou Center for Health Equity, part of the School of Medicine. Despite these lower vitamin D levels and dietary calcium ingestion, blacks naturally experience lower rates of osteoporosis and have far less calcium in their arteries. Studies further reveal that black patients with diabetes have half the rate of heart attack as whites, when provided equal access to health care. This shows that lower levels of calcified atherosclerotic plaque in blacks are associated with a lower risk of heart disease. However, blacks in the general community have higher rates of heart attack than whites, potentially due to unequal access to medical care, Freedman said.
The research team determined the relationship between circulating vitamin D levels and arterial calcium in 340 black men and women with type 2 diabetes. Calcium can deposit in blood vessel walls forming a bone-like material called "calcified atherosclerotic plaque" and this plaque can be detected by computed tomography (CT) scans. Calcified atherosclerotic plaque is a reliable predictor of risk for heart attack and stroke. The investigators measured vitamin D levels in all study participants and then performed a CT scan to detect calcium in the heart and major arteries.
"We found that higher circulating levels of vitamin D in blacks were associated with more calcium in the artery walls," Freedman said. "This is the opposite effect of what is felt to occur in white patients and shows that the accepted "normal" range of vitamin D may be different between blacks and whites.
"Many of these study patients would be placed on supplemental vitamin D by their physicians simply because their levels were felt to be in the low range." Freedman added that physicians should use caution in supplementing vitamin D levels in blacks – especially if they do not have weak bones or other reasons to take this vitamin – until the effects of supplementing vitamin D on blood vessels and heart disease are better understood.
"Doctors frequently prescribe supplemental vitamin D," Freedman said. "However, we do not know all of its effects and how they may differ between the races. The bottom line is that racial differences in calcium handling are seen and black and white patients have differing risk for bone and heart disease. We should more clearly determine the effects of supplementing vitamin D in black patients with low levels based on existing criteria and should not assume that the effects of supplementation will be the same between the races."
The study is the first to show a positive relationship between calcified plaque in large arteries, a measure of atherosclerosis or "hardening of the arteries," and circulating vitamin D levels in black patients. It appears in the March issue of the Journal of Clinical Endocrinology and Metabolism.
"In black patients, lower levels of vitamin D may not signify deficiency to the same extent as in whites," said the study's lead investigator, Barry I. Freedman, M.D., John H. Felts III Professor and chief of the section on nephrology at the School of Medicine "We should use caution when supplementing vitamin D in black patients while we investigate if we are actually worsening calcium deposition in the arteries with treatment."
Vitamin D is widely used to treat patients with osteoporosis and/or low vitamin D levels based on a medically accepted normal range. This "normal" range is typically applied to all race groups, although it was established predominantly in whites. It is thought that as low vitamin D levels rise to the normal range with supplementation, protection from bone and heart disease (atherosclerosis) may increase, as well.
Blacks generally have lower vitamin D levels than whites, partly because their darker skin pigmentation limits the amount of the vitamin produced by sunlight. Blacks also consume fewer dairy products and ingest less dietary calcium than whites, said Freedman, an affiliate of the Maya Angelou Center for Health Equity, part of the School of Medicine. Despite these lower vitamin D levels and dietary calcium ingestion, blacks naturally experience lower rates of osteoporosis and have far less calcium in their arteries. Studies further reveal that black patients with diabetes have half the rate of heart attack as whites, when provided equal access to health care. This shows that lower levels of calcified atherosclerotic plaque in blacks are associated with a lower risk of heart disease. However, blacks in the general community have higher rates of heart attack than whites, potentially due to unequal access to medical care, Freedman said.
The research team determined the relationship between circulating vitamin D levels and arterial calcium in 340 black men and women with type 2 diabetes. Calcium can deposit in blood vessel walls forming a bone-like material called "calcified atherosclerotic plaque" and this plaque can be detected by computed tomography (CT) scans. Calcified atherosclerotic plaque is a reliable predictor of risk for heart attack and stroke. The investigators measured vitamin D levels in all study participants and then performed a CT scan to detect calcium in the heart and major arteries.
"We found that higher circulating levels of vitamin D in blacks were associated with more calcium in the artery walls," Freedman said. "This is the opposite effect of what is felt to occur in white patients and shows that the accepted "normal" range of vitamin D may be different between blacks and whites.
"Many of these study patients would be placed on supplemental vitamin D by their physicians simply because their levels were felt to be in the low range." Freedman added that physicians should use caution in supplementing vitamin D levels in blacks – especially if they do not have weak bones or other reasons to take this vitamin – until the effects of supplementing vitamin D on blood vessels and heart disease are better understood.
"Doctors frequently prescribe supplemental vitamin D," Freedman said. "However, we do not know all of its effects and how they may differ between the races. The bottom line is that racial differences in calcium handling are seen and black and white patients have differing risk for bone and heart disease. We should more clearly determine the effects of supplementing vitamin D in black patients with low levels based on existing criteria and should not assume that the effects of supplementation will be the same between the races."
Saturday, March 13, 2010
Short bursts of intense exercise better than long, less strenuous
*
High-Intensity Interval Training Is Time-Efficient and Effective, Study Suggests
The usual excuse of "lack of time" for not doing enough exercise is blown away by new research published in The Journal of Physiology.
The study, from scientists at Canada's McMaster University, adds to the growing evidence for the benefits of short term high-intensity interval training (HIT) as a time-efficient but safe alternative to traditional types of moderate long term exercise. Astonishingly, it is possible to get more by doing less!
"We have shown that interval training does not have to be 'all out' in order to be effective," says Professor Martin Gibala. "Doing 10 one-minute sprints on a standard stationary bike with about one minute of rest in between, three times a week, works as well in improving muscle as many hours of conventional long-term biking less strenuously."
HIT means doing a number of short bursts of intense exercise with short recovery breaks in between. The authors have already shown with young healthy college students that this produces the same physical benefits as conventional long duration endurance training despite taking much less time (and amazingly, actually doing less exercise!) However, their previous work used a relatively extreme set-up that involved "all out" pedaling on a specialized laboratory bicycle. The new study used a standard stationary bicycle and a workload which was still above most people's comfort zone -about 95% of maximal heart rate -- but only about half of what can be achieved when people sprint at an all-out pace.
This less extreme HIT method may work well for people (the older, less fit, and slightly overweight among us) whose doctors might have worries about them exercising "all-out." We have known for years that repeated moderate long-term exercise tunes up fuel and oxygen delivery to muscles and aids the removal of waste products. Exercise also improves the way muscles use the oxygen to burn the fuel in mitochondria, the microscopic power station of cells.
Running or cycling for hours a week widens the network of vessels supplying muscle cells and also boosts the numbers of mitochondria in them so that a person can carry out activities of daily living more effectively and without strain, and crucially with less risk of a heart attack, stroke or diabetes.
But the traditional approach to exercise is time consuming. Martin Gibala and his team have shown that the same results can be obtained in far less time with brief spurts of higher-intensity exercise.
To achieve the study's equivalent results by endurance training you'd need to complete over 10 hours of continuous moderate bicycling exercise over a two-week period.
The "secret" to why HIT is so effective is unclear. However, the study by Gibala and co-workers also provides insight into the molecular signals that regulate muscle adaptation to interval training. It appears that HIT stimulates many of the same cellular pathways that are responsible for the beneficial effects we associate with endurance training.
The upside of doing more exercise is well-known, but a big question for most people thinking of getting fit is: "How much time out of my busy life do I need to spend to get the perks?"
Martin Gibala says "no time to exercise" is not an excuse now that HIT can be tailored for the average adult. "While still a demanding form of training," Gibala adds, "the exercise protocol we used should be possible to do by the general public and you don't need more than an average exercise bike."
The McMaster team's future research will examine whether HIT can bring health benefits to people who are overweight or who have metabolic diseases like diabetes.
As the evidence for HIT continues to grow, a new frontier in the fitness field emerges.
High-Intensity Interval Training Is Time-Efficient and Effective, Study Suggests
The usual excuse of "lack of time" for not doing enough exercise is blown away by new research published in The Journal of Physiology.
The study, from scientists at Canada's McMaster University, adds to the growing evidence for the benefits of short term high-intensity interval training (HIT) as a time-efficient but safe alternative to traditional types of moderate long term exercise. Astonishingly, it is possible to get more by doing less!
"We have shown that interval training does not have to be 'all out' in order to be effective," says Professor Martin Gibala. "Doing 10 one-minute sprints on a standard stationary bike with about one minute of rest in between, three times a week, works as well in improving muscle as many hours of conventional long-term biking less strenuously."
HIT means doing a number of short bursts of intense exercise with short recovery breaks in between. The authors have already shown with young healthy college students that this produces the same physical benefits as conventional long duration endurance training despite taking much less time (and amazingly, actually doing less exercise!) However, their previous work used a relatively extreme set-up that involved "all out" pedaling on a specialized laboratory bicycle. The new study used a standard stationary bicycle and a workload which was still above most people's comfort zone -about 95% of maximal heart rate -- but only about half of what can be achieved when people sprint at an all-out pace.
This less extreme HIT method may work well for people (the older, less fit, and slightly overweight among us) whose doctors might have worries about them exercising "all-out." We have known for years that repeated moderate long-term exercise tunes up fuel and oxygen delivery to muscles and aids the removal of waste products. Exercise also improves the way muscles use the oxygen to burn the fuel in mitochondria, the microscopic power station of cells.
Running or cycling for hours a week widens the network of vessels supplying muscle cells and also boosts the numbers of mitochondria in them so that a person can carry out activities of daily living more effectively and without strain, and crucially with less risk of a heart attack, stroke or diabetes.
But the traditional approach to exercise is time consuming. Martin Gibala and his team have shown that the same results can be obtained in far less time with brief spurts of higher-intensity exercise.
To achieve the study's equivalent results by endurance training you'd need to complete over 10 hours of continuous moderate bicycling exercise over a two-week period.
The "secret" to why HIT is so effective is unclear. However, the study by Gibala and co-workers also provides insight into the molecular signals that regulate muscle adaptation to interval training. It appears that HIT stimulates many of the same cellular pathways that are responsible for the beneficial effects we associate with endurance training.
The upside of doing more exercise is well-known, but a big question for most people thinking of getting fit is: "How much time out of my busy life do I need to spend to get the perks?"
Martin Gibala says "no time to exercise" is not an excuse now that HIT can be tailored for the average adult. "While still a demanding form of training," Gibala adds, "the exercise protocol we used should be possible to do by the general public and you don't need more than an average exercise bike."
The McMaster team's future research will examine whether HIT can bring health benefits to people who are overweight or who have metabolic diseases like diabetes.
As the evidence for HIT continues to grow, a new frontier in the fitness field emerges.
Friday, March 12, 2010
Vitamin D and Calcium Interplay Explored
Increasing calcium intake is a common--yet not always successful--strategy for reducing bone fractures. But a study supported in part by the Agricultural Research Service (ARS) underscores the importance of vitamin D and its ability to help the body utilize calcium. The study also may explain why increasing calcium alone isn’t always successful in dealing with this problem.
Currently, calcium intake recommendations are not tied to vitamin D status, which may explain why markedly different recommended calcium intakes exist among countries. In the United States, the recommended calcium intake is 1,200 milligrams (mg) daily for adults aged 50 and older.
The body's skeleton needs adequate dietary calcium to reach its full potential in terms of bone mass. Still, many other factors affect bone mass, such as exercise, smoking and vitamin D--the latter through its effect on calcium absorption and direct effect on the skeleton.
The study involved a close look at about 10,000 men and women aged 20 and older participating in a nationally representative survey. Coauthors included nutrition specialist Bess Dawson Hughes with the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts University in Boston, Mass. Dawson Hughes is director of the HNRCA Bone Laboratory.
Blood levels of 25-hydroxyvitamin D are used as the primary indicator of vitamin D adequacy. Within the study sample of U.S. adults, a large fraction of younger and older adults were below a suggested desirable serum vitamin D concentration of at least 75 nanomoles-per-liter (nmol/L).
The study supports the idea that correcting inadequate blood levels of vitamin D is more important than increasing dietary calcium intake beyond 566 mg a day among women and 626 mg a day among men for better bone mineral density. For example, a higher calcium intake beyond 566 mg a day may only be important among women whose vitamin D concentrations are low (less than 50 nmol/L), according to authors.
Details of this study can be found in the publication Journal of Bone and Mineral Research.
ARS is the U.S. Department of Agriculture’s (USDA) principal intramural scientific research agency. The research supports the USDA priority of improving nutrition and health.
Currently, calcium intake recommendations are not tied to vitamin D status, which may explain why markedly different recommended calcium intakes exist among countries. In the United States, the recommended calcium intake is 1,200 milligrams (mg) daily for adults aged 50 and older.
The body's skeleton needs adequate dietary calcium to reach its full potential in terms of bone mass. Still, many other factors affect bone mass, such as exercise, smoking and vitamin D--the latter through its effect on calcium absorption and direct effect on the skeleton.
The study involved a close look at about 10,000 men and women aged 20 and older participating in a nationally representative survey. Coauthors included nutrition specialist Bess Dawson Hughes with the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts University in Boston, Mass. Dawson Hughes is director of the HNRCA Bone Laboratory.
Blood levels of 25-hydroxyvitamin D are used as the primary indicator of vitamin D adequacy. Within the study sample of U.S. adults, a large fraction of younger and older adults were below a suggested desirable serum vitamin D concentration of at least 75 nanomoles-per-liter (nmol/L).
The study supports the idea that correcting inadequate blood levels of vitamin D is more important than increasing dietary calcium intake beyond 566 mg a day among women and 626 mg a day among men for better bone mineral density. For example, a higher calcium intake beyond 566 mg a day may only be important among women whose vitamin D concentrations are low (less than 50 nmol/L), according to authors.
Details of this study can be found in the publication Journal of Bone and Mineral Research.
ARS is the U.S. Department of Agriculture’s (USDA) principal intramural scientific research agency. The research supports the USDA priority of improving nutrition and health.
Tuesday, March 9, 2010
Latest Health Research
Most recent health posts:
February 20
February 3
Here's today's summary of health research published since February 21 and my reactions:
Now, I definitely have to keep playing soccer until I’m 70:
Soccer reduces risk of falls and bone fractures
Regular participation in soccer increases both bone mass and bone density, causes a significant improvement in standing postural balance and improves muscle strength. Together, these effects reduce the risk of falls and bone fractures…. the short- and long-term training effects on bone mineral density were greater for the soccer players than for a similar group of runners… The research shows that 70-year-old men, who have played soccer most of their lives on a recreational basis, have just as good a balance and rapid muscle strength as untrained 30-year-olds and much better balance and muscle strength than their peers.
But;
Watching World Cup Soccer Could Kill You!
I’m glad that I take Vitamin D – the most recent news is stunning:
Vitamin D is Crucial To Activating Immune Defenses
Scientists at the University of Copenhagen have discovered that Vitamin D is crucial to activating our immune defenses and that without sufficient intake of the vitamin, the killer cells of the immune system – T cells - will not be able to react to and fight off serious infections in the body.
For T cells to detect and kill foreign pathogens such as clumps of bacteria or viruses, the cells must first be 'triggered' into action and 'transform' from inactive and harmless immune cells into killer cells that are primed to seek out and destroy all traces of a foreign pathogen.
The researchers found that the T cells rely on vitamin D in order to activate and they would remain dormant, 'naïve' to the possibility of threat if vitamin D is lacking in the blood.
And there's more:
Vitamin D lowers kidney cancer risk in men
Research suggests that vitamin D, which is obtained from sun exposure, some foods, and from supplements, may help prevent some cancers. Vitamin D is metabolized and most active within the kidneys. According to a new study, men employed in occupations with potential exposure to high levels of sunlight have a reduced risk of kidney cancer compared with men who were less likely to be exposed to sunlight at work.
Vitamin D Improves Mood
A daily dose of vitamin D lifts mood during cold weather months - vitamin D may be an important addition to care for diabetes and depression.
Low Low levels of Vitamin D linked to muscle fat, decreased strength in young
59 per cent of study subjects had too little Vitamin D in their blood. Nearly a quarter of the group had serious deficiencies (less than 20 ng/ml) of this important vitamin. Since Vitamin D insufficiency is linked to increased body fat, decreased muscle strength and a range of disorders, this is a serious health issue…. Abnormal levels of Vitamin D are associated with a whole spectrum of diseases, including cancer, osteoporosis and diabetes, as well as cardiovascular and autoimmune disorders.
The study results are especially surprising, because study subjects – all healthy young women living in California – could logically be expected to benefit from good diet, outdoor activities and ample exposure to sunshine – the trigger that causes the body to produce Vitamin D.
I keep most of my vitamins in my office, which is good:
Vitamins stored in bathrooms, kitchens may become less effective
High humidity present in bathrooms and kitchens could be degrading the vitamins and health supplements stored in those rooms, even if the lids are on tight.
Why didn’t they test men:
Women who drink moderately appear to gain less weight than nondrinkers
Normal-weight women who drink a light to moderate amount of alcohol appear to gain less weight and have a lower risk of becoming overweight and obese than non-drinkers…
Women who did not drink alcohol at all gained the most weight, with weight gain decreasing as alcohol intake increased … with the strongest association found for red wine .
I don’t drink coffee but maybe lots of tea has the same effect:
Coffee = Reduced Risk of Heart Rhythm Disturbances
I eat oats, apples and nuts almost every day:
Study shows soluble fiber boosts immune system
A new University of Illinois study touts the benefits of soluble fiber—found in oats, apples, and nuts, for starters—saying that it reduces the inflammation associated with obesity-related diseases and strengthens the immune system. This happens because soluble fiber causes increased production of an anti-inflammatory protein called interleukin-4. Insoluble fiber, found in whole wheat and whole-grain products, wheat bran, and green, leafy vegetables, is also valuable for providing bulk and helping food move through the digestive system, but it doesn't provide the boost to the immune system that soluble fiber provides.
I’m pretty good abut taking my statin substitute almost every day:
Take your statins
Only 68 percent of corporate executives took their cholesterol lowering medication as prescribed by a doctor, a new study shows. Overall, the executives who took their medication even sporadically were twice as likely to meet their cholesterol goals….Statin drugs lower the low-density lipoprotein (LDL) cholesterol, or the so-called bad cholesterol. Statins are proven effective and are a first-line treatment for lowering cholesterol.
Adherence was defined as taking medication as prescribed at least 80 percent of the time. Overall, statin users were twice as likely to meet the near optimal goal of 130 mg/dL or less, than non-statin users. Among executive who took statins, 70 percent achieved the near-optimal goal and 30 percent achieved the optimal goal of 100 mg/dL or less, compared to 55 percent and 21 percent, respectively, for non-statin users who weren't prescribed the drug.
My wife has completely banned garlic from my diet, which is too bad:
GARLIC’S CANCER-FIGHTING POTENTIAL
I had a colonoscopy performed by a gastroenterologist:
Patients Who Have Colonoscopy Performed by Gastroenterologists Less Likely to Develop Colorectal Cancer
I can’t eat eat ice cream or drink milk without stomach pains, but cheese and yogurt don’t bother me – and I do eat a lot of yogurt:
Avoiding dairy due to lactose intolerance is unnecessary in most cases
People may avoid milk and other dairy products due to concerns about lactose intolerance, but eliminating these nutrient-rich foods may not only be unnecessary to manage the condition – it could impact diet and health.,, Try small, frequent portions or buying lactose-free or lactose-reduced milk – which contain all the same nutrients as regular milk. Yogurt and hard cheeses (the panel suggests cheddar, provolone and mozzarella) may also be more easily digested.
I do take naps a few times a week – perhaps I should do it more often:
A midday nap markedly boosts the brain's learning capacity
New research from the University of California, Berkeley, shows that an hour's nap can dramatically boost and restore your brain power. Indeed, the findings suggest that a biphasic sleep schedule not only refreshes the mind, but can make you smarter.
I guess I don’t need magnesium supplements after all, which is just as well since I forgot to buy them:
Magnesium Helps You Remember - But Not Supplements
Magnesium, a key nutrient for the functioning of memory, may be even more critical than previously thought for the neurons of children and healthy brain cells in adults… Today's over-the-counter magnesium supplements don't really work. They do not get into the brain.
…Dr. Slutsky advises people to get their magnesium the old-fashioned way — by eating lots of green leaves, broccoli, almonds, cashews and fruit. The effects on memory won't appear overnight, she cautions, but with this persistent change in diet, memory should improve, and the effects of dementia and other cognitive impairment diseases related to aging may be considerably delayed.
Blogging makes me feel young, and I learn a lot doing it, which is good:
You're only as old as you feel really seems to be true, at least cognitively.
Learning helps keep brain healthy
February 20
February 3
Here's today's summary of health research published since February 21 and my reactions:
Now, I definitely have to keep playing soccer until I’m 70:
Soccer reduces risk of falls and bone fractures
Regular participation in soccer increases both bone mass and bone density, causes a significant improvement in standing postural balance and improves muscle strength. Together, these effects reduce the risk of falls and bone fractures…. the short- and long-term training effects on bone mineral density were greater for the soccer players than for a similar group of runners… The research shows that 70-year-old men, who have played soccer most of their lives on a recreational basis, have just as good a balance and rapid muscle strength as untrained 30-year-olds and much better balance and muscle strength than their peers.
But;
Watching World Cup Soccer Could Kill You!
I’m glad that I take Vitamin D – the most recent news is stunning:
Vitamin D is Crucial To Activating Immune Defenses
Scientists at the University of Copenhagen have discovered that Vitamin D is crucial to activating our immune defenses and that without sufficient intake of the vitamin, the killer cells of the immune system – T cells - will not be able to react to and fight off serious infections in the body.
For T cells to detect and kill foreign pathogens such as clumps of bacteria or viruses, the cells must first be 'triggered' into action and 'transform' from inactive and harmless immune cells into killer cells that are primed to seek out and destroy all traces of a foreign pathogen.
The researchers found that the T cells rely on vitamin D in order to activate and they would remain dormant, 'naïve' to the possibility of threat if vitamin D is lacking in the blood.
And there's more:
Vitamin D lowers kidney cancer risk in men
Research suggests that vitamin D, which is obtained from sun exposure, some foods, and from supplements, may help prevent some cancers. Vitamin D is metabolized and most active within the kidneys. According to a new study, men employed in occupations with potential exposure to high levels of sunlight have a reduced risk of kidney cancer compared with men who were less likely to be exposed to sunlight at work.
Vitamin D Improves Mood
A daily dose of vitamin D lifts mood during cold weather months - vitamin D may be an important addition to care for diabetes and depression.
Low Low levels of Vitamin D linked to muscle fat, decreased strength in young
59 per cent of study subjects had too little Vitamin D in their blood. Nearly a quarter of the group had serious deficiencies (less than 20 ng/ml) of this important vitamin. Since Vitamin D insufficiency is linked to increased body fat, decreased muscle strength and a range of disorders, this is a serious health issue…. Abnormal levels of Vitamin D are associated with a whole spectrum of diseases, including cancer, osteoporosis and diabetes, as well as cardiovascular and autoimmune disorders.
The study results are especially surprising, because study subjects – all healthy young women living in California – could logically be expected to benefit from good diet, outdoor activities and ample exposure to sunshine – the trigger that causes the body to produce Vitamin D.
I keep most of my vitamins in my office, which is good:
Vitamins stored in bathrooms, kitchens may become less effective
High humidity present in bathrooms and kitchens could be degrading the vitamins and health supplements stored in those rooms, even if the lids are on tight.
Why didn’t they test men:
Women who drink moderately appear to gain less weight than nondrinkers
Normal-weight women who drink a light to moderate amount of alcohol appear to gain less weight and have a lower risk of becoming overweight and obese than non-drinkers…
Women who did not drink alcohol at all gained the most weight, with weight gain decreasing as alcohol intake increased … with the strongest association found for red wine .
I don’t drink coffee but maybe lots of tea has the same effect:
Coffee = Reduced Risk of Heart Rhythm Disturbances
I eat oats, apples and nuts almost every day:
Study shows soluble fiber boosts immune system
A new University of Illinois study touts the benefits of soluble fiber—found in oats, apples, and nuts, for starters—saying that it reduces the inflammation associated with obesity-related diseases and strengthens the immune system. This happens because soluble fiber causes increased production of an anti-inflammatory protein called interleukin-4. Insoluble fiber, found in whole wheat and whole-grain products, wheat bran, and green, leafy vegetables, is also valuable for providing bulk and helping food move through the digestive system, but it doesn't provide the boost to the immune system that soluble fiber provides.
I’m pretty good abut taking my statin substitute almost every day:
Take your statins
Only 68 percent of corporate executives took their cholesterol lowering medication as prescribed by a doctor, a new study shows. Overall, the executives who took their medication even sporadically were twice as likely to meet their cholesterol goals….Statin drugs lower the low-density lipoprotein (LDL) cholesterol, or the so-called bad cholesterol. Statins are proven effective and are a first-line treatment for lowering cholesterol.
Adherence was defined as taking medication as prescribed at least 80 percent of the time. Overall, statin users were twice as likely to meet the near optimal goal of 130 mg/dL or less, than non-statin users. Among executive who took statins, 70 percent achieved the near-optimal goal and 30 percent achieved the optimal goal of 100 mg/dL or less, compared to 55 percent and 21 percent, respectively, for non-statin users who weren't prescribed the drug.
My wife has completely banned garlic from my diet, which is too bad:
GARLIC’S CANCER-FIGHTING POTENTIAL
I had a colonoscopy performed by a gastroenterologist:
Patients Who Have Colonoscopy Performed by Gastroenterologists Less Likely to Develop Colorectal Cancer
I can’t eat eat ice cream or drink milk without stomach pains, but cheese and yogurt don’t bother me – and I do eat a lot of yogurt:
Avoiding dairy due to lactose intolerance is unnecessary in most cases
People may avoid milk and other dairy products due to concerns about lactose intolerance, but eliminating these nutrient-rich foods may not only be unnecessary to manage the condition – it could impact diet and health.,, Try small, frequent portions or buying lactose-free or lactose-reduced milk – which contain all the same nutrients as regular milk. Yogurt and hard cheeses (the panel suggests cheddar, provolone and mozzarella) may also be more easily digested.
I do take naps a few times a week – perhaps I should do it more often:
A midday nap markedly boosts the brain's learning capacity
New research from the University of California, Berkeley, shows that an hour's nap can dramatically boost and restore your brain power. Indeed, the findings suggest that a biphasic sleep schedule not only refreshes the mind, but can make you smarter.
I guess I don’t need magnesium supplements after all, which is just as well since I forgot to buy them:
Magnesium Helps You Remember - But Not Supplements
Magnesium, a key nutrient for the functioning of memory, may be even more critical than previously thought for the neurons of children and healthy brain cells in adults… Today's over-the-counter magnesium supplements don't really work. They do not get into the brain.
…Dr. Slutsky advises people to get their magnesium the old-fashioned way — by eating lots of green leaves, broccoli, almonds, cashews and fruit. The effects on memory won't appear overnight, she cautions, but with this persistent change in diet, memory should improve, and the effects of dementia and other cognitive impairment diseases related to aging may be considerably delayed.
Blogging makes me feel young, and I learn a lot doing it, which is good:
You're only as old as you feel really seems to be true, at least cognitively.
Learning helps keep brain healthy
February 20 Summary Report
I don’t eat or cook much meat, which is good, as reported here:
and here:
I try to keep a positive attitude, and I'm generally pretty happy and content, which is good according to this report:
I do drink lots of good tea, which is good:
And I take aspirin regularly, for which there is more good news:
But unfortunately, don't take ibuprofen:
I get a lot of fiber from fruits, vegetables and oatmeal, which is good:
and it turns out oatmeal, which I eat almost every day, is even better for you than previously thought:
I take Vitamin D:
And the statin substitute red yeast rice, but I'm thinking of asking for a prescription to the real thing, as evidence mounts for all the good things statins do for you. This is just the latest:
I'm eating more blueberries and blackberries lately because of reports here:
and here:
You are what you eat:
Mediterranean diet (yes):
Dark chocolate (yes) or, apparently, even small amounts of any chocolate:
And what you drink:
Beer (not nearly enough, alas - red wine instead):
Milk (no):
Soda (no!)
Frying meat on a gas burner may be more harmful to health than using an electric burner, because of the type of fumes it produces. Cooking fumes produced during high temperature frying have recently been classified as "probably carcinogenic" by the International Agency for Research on Cancer (IARC).
and here:
Heterocyclic amines (HCAs) are mutagenic compounds that form when meat and fish are cooked at high temperatures especially meats that are grilled, pan-fried, broiled, or barbecued. The National Toxicology Program of the U.S. Department of Health and Human Services categorizes HCAs as human carcinogens that can increase the risk of certain types of cancers.
I try to keep a positive attitude, and I'm generally pretty happy and content, which is good according to this report:
People who are usually happy, enthusiastic and content are less likely to develop heart disease than those who tend not to be happy.
I do drink lots of good tea, which is good:
Scientists have confirmed that the healthful substances found in green tea, renowned for their powerful antioxidant and disease-fighting properties, do penetrate into tissues of the eye. Their new report, the first documenting how the lens, retina, and other eye tissues absorb these substances, raises the possibility that green tea may protect against glaucoma and other common eye diseases.
And I take aspirin regularly, for which there is more good news:
Women who have completed treatment for early-stage breast cancer and who take aspirin have a nearly 50 percent reduced risk of breast cancer death and a similar reduction in the risk of metastasis.
But unfortunately, don't take ibuprofen:
The study found regular users of ibuprofen were 40 percent less likely to develop Parkinson's disease than people who didn't take ibuprofen. Also, people who took higher amounts of ibuprofen were less likely to develop Parkinson's disease than people who took smaller amounts of the drug. The results were the same regardless of age, smoking and caffeine intake.
I get a lot of fiber from fruits, vegetables and oatmeal, which is good:
Fiber not only increases the bulk of the food and moves it through the gastrointestinal tract more rapidly, but also helps in preventing constipation and possible colon and rectal cancer. Intake of fiber through various foods such as nuts, whole-grain flour, fruits, and vegetables is now associated with decreased low-density lipoprotein (LDL)-cholesterol, lower insulin demand, increased stool bulk, softening of fecal contents, and improved laxative properties. Epidemiological studies have correlated high consumption of fiber with lower incidence of certain diseases such as cardiovascular and cancer of colon and rectum. Several conditions such as diabetes, atherosclerosis, breast cancer, diverticulitis, hemorrhoids have been connected to a low intake of fiber.
and it turns out oatmeal, which I eat almost every day, is even better for you than previously thought:
Oats may contribute to the relaxation of arteries and the prevention of atherosclerosis.Consumption of oats reduces blood pressure and chronic inflammation of the arterial wall, part of the process that eventually causes disease. These studies provide additional indications of the potential health benefit of oat consumption in the prevention of coronary heart disease beyond its known effect through lowering blood cholesterol. Findings from a more recent study soon to be published suggest that consuming oats and oat bran may reduce the risk of colon cancer, not only through high fiber content, but also through avenanthramides that slow or discourage proliferation of colon cancer cells.
I take Vitamin D:
Middle aged and elderly people with high levels of vitamin D could reduce their chances of developing heart disease or diabetes by 43%, according to researchers at the University of Warwick.
And the statin substitute red yeast rice, but I'm thinking of asking for a prescription to the real thing, as evidence mounts for all the good things statins do for you. This is just the latest:
Statins, a class of drugs used to lower cholesterol levels, have been successfully fighting heart disease for years. A new study has now found that the same drugs cut the risks of cataracts in men by almost 40%. One recent study, featured as part of a Time magazine cover story, showed that statins can reduce a person's chance of dying from all combined diseases and conditions by 40%, something in the medical community called "all-cause mortality."
I'm eating more blueberries and blackberries lately because of reports here:
Could eating blueberries help get rid of belly fat? And could a blueberry-enriched diet stem the conditions that lead to diabetes? New research gives tantalizing clues to the potential of blueberries in reducing risk factors for cardiovascular disease and metabolic syndrome. The effect is thought to be due to the high level of phytochemicals _ naturally occurring antioxidants _ that blueberries contain.
and here:
It is already known that blueberries are rich in antioxidants and vitamins. New research shows that blueberry fibre are important and can alleviate and protect against intestinal inflammations, such as ulcerative colitis.
You are what you eat:
Mediterranean diet (yes):
The Mediterranean diet may be best known as a heart-healthy eating plan, but some studies suggest that it may also reduce the risk of diabetes, certain cancers, obesity and Alzheimer s disease.
Dark chocolate (yes) or, apparently, even small amounts of any chocolate:
Chocolate consumption once a week as opposed to none per week may lower their risk of stroke and the risk of death after suffering a stroke.
And what you drink:
Beer (not nearly enough, alas - red wine instead):
A new study suggests that beer is a significant source of dietary silicon, a key ingredient for increasing bone mineral density and connective tissue. Moderate beer consumption may help fight osteoporosis, a disease of the skeletal system characterized by low bone mass and deterioration of bone tissue.
Milk (no):
Drinking milk during pregnancy may help reduce your baby's chances of developing multiple sclerosis (MS) as an adult.
Soda (no!)
Consuming two or more soft drinks per week increased the risk of developing pancreatic cancer by nearly twofold compared to individuals who did not consume soft drinks, according to a report in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research. Although relatively rare, pancreatic cancer remains one of the most deadly, and only 5 percent of people who are diagnosed are alive five years later. No association was seen between fruit juice consumption and pancreatic cancer.
Monday, March 8, 2010
Women who drink moderately appear to gain less weight than nondrinkers
*
Red wine best
Normal-weight women who drink a light to moderate amount of alcohol appear to gain less weight and have a lower risk of becoming overweight and obese than non-drinkers, according to a report in the March 8 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
More than half of American adults drink alcoholic beverages, according to background information in the article. Alcohol contains about 7 calories per gram (with approximately 28 grams per ounce) and alcohol drinking may possibly lead to weight gain through an imbalance of energy consumed and energy burned. However, research has not consistently provided evidence that consuming alcohol is a risk factor for obesity.
Lu Wang, M.D., Ph.D., of Brigham and Women's Hospital, Boston, and colleagues studied 19,220 U.S. women age 39 or older who had a body mass index (BMI) in the range classified as normal (18.5 to 25). On an initial questionnaire, participants reported how many alcoholic beverages they typically drank per day. A total of 7,346 (38.2 percent) reported drinking no alcohol; 6,312 (32.8 percent) drank less than 5 grams; 3,865 (20.1 percent) drank 5 to less than 15 grams; 1,129 (5.9 percent) drank 15 to less than 30 grams; and 568 (3 percent) drank 30 grams per day or more.
Over an average of 13 years of follow-up, women on average gained weight progressively. Women who did not drink alcohol at all gained the most weight, with weight gain decreasing as alcohol intake increased. A total of 7,942 (41.3 percent) women who initially had normal weight become overweight or obese (BMI of 25 or higher), including 732 (3.8 percent) who become obese (BMI of 30 or higher). Compared with women who did not drink at all, those who consumed some but less than 40 grams per day of alcohol were less likely to become overweight or obese. Women who drank 15 to less than 30 grams per day had the lowest risk, which was almost 30 percent lower than that of non-drinkers.
"An inverse association between alcohol intake and risk of becoming overweight or obese was noted for all four types of alcoholic beverages [red wine, white wine, beer and liquor], with the strongest association found for red wine and a weak yet significant association for white wine after multivariate adjustment," the authors write.
The authors caution that, given potential medical and psychosocial problems related to drinking alcohol, its beneficial and adverse effects for each individual must be considered before making any recommendation about its use. "Further investigations are warranted to elucidate the role of alcohol intake and alcohol metabolism in energy balance and to identify behavioral, physiological and genetic factors that may modify the alcohol effects," they conclude.
Red wine best
Normal-weight women who drink a light to moderate amount of alcohol appear to gain less weight and have a lower risk of becoming overweight and obese than non-drinkers, according to a report in the March 8 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
More than half of American adults drink alcoholic beverages, according to background information in the article. Alcohol contains about 7 calories per gram (with approximately 28 grams per ounce) and alcohol drinking may possibly lead to weight gain through an imbalance of energy consumed and energy burned. However, research has not consistently provided evidence that consuming alcohol is a risk factor for obesity.
Lu Wang, M.D., Ph.D., of Brigham and Women's Hospital, Boston, and colleagues studied 19,220 U.S. women age 39 or older who had a body mass index (BMI) in the range classified as normal (18.5 to 25). On an initial questionnaire, participants reported how many alcoholic beverages they typically drank per day. A total of 7,346 (38.2 percent) reported drinking no alcohol; 6,312 (32.8 percent) drank less than 5 grams; 3,865 (20.1 percent) drank 5 to less than 15 grams; 1,129 (5.9 percent) drank 15 to less than 30 grams; and 568 (3 percent) drank 30 grams per day or more.
Over an average of 13 years of follow-up, women on average gained weight progressively. Women who did not drink alcohol at all gained the most weight, with weight gain decreasing as alcohol intake increased. A total of 7,942 (41.3 percent) women who initially had normal weight become overweight or obese (BMI of 25 or higher), including 732 (3.8 percent) who become obese (BMI of 30 or higher). Compared with women who did not drink at all, those who consumed some but less than 40 grams per day of alcohol were less likely to become overweight or obese. Women who drank 15 to less than 30 grams per day had the lowest risk, which was almost 30 percent lower than that of non-drinkers.
"An inverse association between alcohol intake and risk of becoming overweight or obese was noted for all four types of alcoholic beverages [red wine, white wine, beer and liquor], with the strongest association found for red wine and a weak yet significant association for white wine after multivariate adjustment," the authors write.
The authors caution that, given potential medical and psychosocial problems related to drinking alcohol, its beneficial and adverse effects for each individual must be considered before making any recommendation about its use. "Further investigations are warranted to elucidate the role of alcohol intake and alcohol metabolism in energy balance and to identify behavioral, physiological and genetic factors that may modify the alcohol effects," they conclude.
Vitamin D lowers kidney cancer risk in men
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Occupational sunlight exposure and kidney cancer risk in men
According to a new study, men employed in occupations with potential exposure to high levels of sunlight have a reduced risk of kidney cancer compared with men who were less likely to be exposed to sunlight at work. The study did not find an association between occupational sunlight exposure and kidney cancer risk in women. Published early online in CANCER, a peer-reviewed journal of the American Cancer Society, the study is the largest case-control study of kidney cancer to investigate the association with occupational sunlight exposure. The study, however, did not include information on non-occupational sunlight exposure and does not address directly whether sunlight exposure can help prevent kidney cancer.
Research suggests that vitamin D, which is obtained from sun exposure, some foods, and from supplements, may help prevent some cancers. Vitamin D is metabolized and most active within the kidneys. Because both the incidence of kidney cancer and the prevalence of vitamin D deficiency have increased over the past few decades, Sara Karami, PhD, of the National Cancer Institute in Rockville, MD, and her colleagues designed a study to explore whether occupational sunlight exposure is associated with kidney cancer risk.
The study included 1,097 patients with kidney cancer and 1,476 individuals without cancer from four Central and Eastern European countries. Demographic and lifetime occupational information was collected through in-person interviews and occupational sunlight exposure indices were estimated based on industry and job titles. The investigators observed a 24 percent to 38 percent reduction in kidney cancer risk with increasing occupational sunlight exposure among male participants in the study. No association between occupational sunlight exposure and kidney cancer risk was observed among females in the study.
The findings suggest that sunlight exposure may affect kidney cancer risk, although the authors have no explanation for the apparent differences in risk between men and women. They offer several hypotheses for the observed differences. Biological or behavioral differences between men and women may play a role. For example, hormonal differences may influence the body's response to sunlight exposure, females may have a higher tendency to use sunscreen on a regular basis, and men may be prone to working outdoors while shirtless. It is also possible that the observed gender differences in risk were due to confounding by other unmeasured kidney cancer risk factors, such as recreational sunlight exposure and physical activity levels.
While this study's findings raise the possibility of a link between sunlight exposure and kidney cancer risk, "they clearly need to be replicated in other populations and in studies that use better estimates of long-term ultraviolet exposure and vitamin D intake," said Dr. Karami.
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Article: "Occupational sunlight exposure and risk of renal cell carcinoma." Sara Karami, Paolo Boffetta, Patricia Stewart, Nathaniel Rothman, Katherine L. Hunting, Mustafa Dosemeci, Sonja I. Berndt, Paul Brennan, Wong-Ho Chow, and Lee E. Moore. CANCER; Published Online: March 8, 2010 (DOI: 10.1002/cncr.24939).
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Occupational sunlight exposure and kidney cancer risk in men
According to a new study, men employed in occupations with potential exposure to high levels of sunlight have a reduced risk of kidney cancer compared with men who were less likely to be exposed to sunlight at work. The study did not find an association between occupational sunlight exposure and kidney cancer risk in women. Published early online in CANCER, a peer-reviewed journal of the American Cancer Society, the study is the largest case-control study of kidney cancer to investigate the association with occupational sunlight exposure. The study, however, did not include information on non-occupational sunlight exposure and does not address directly whether sunlight exposure can help prevent kidney cancer.
Research suggests that vitamin D, which is obtained from sun exposure, some foods, and from supplements, may help prevent some cancers. Vitamin D is metabolized and most active within the kidneys. Because both the incidence of kidney cancer and the prevalence of vitamin D deficiency have increased over the past few decades, Sara Karami, PhD, of the National Cancer Institute in Rockville, MD, and her colleagues designed a study to explore whether occupational sunlight exposure is associated with kidney cancer risk.
The study included 1,097 patients with kidney cancer and 1,476 individuals without cancer from four Central and Eastern European countries. Demographic and lifetime occupational information was collected through in-person interviews and occupational sunlight exposure indices were estimated based on industry and job titles. The investigators observed a 24 percent to 38 percent reduction in kidney cancer risk with increasing occupational sunlight exposure among male participants in the study. No association between occupational sunlight exposure and kidney cancer risk was observed among females in the study.
The findings suggest that sunlight exposure may affect kidney cancer risk, although the authors have no explanation for the apparent differences in risk between men and women. They offer several hypotheses for the observed differences. Biological or behavioral differences between men and women may play a role. For example, hormonal differences may influence the body's response to sunlight exposure, females may have a higher tendency to use sunscreen on a regular basis, and men may be prone to working outdoors while shirtless. It is also possible that the observed gender differences in risk were due to confounding by other unmeasured kidney cancer risk factors, such as recreational sunlight exposure and physical activity levels.
While this study's findings raise the possibility of a link between sunlight exposure and kidney cancer risk, "they clearly need to be replicated in other populations and in studies that use better estimates of long-term ultraviolet exposure and vitamin D intake," said Dr. Karami.
###
Article: "Occupational sunlight exposure and risk of renal cell carcinoma." Sara Karami, Paolo Boffetta, Patricia Stewart, Nathaniel Rothman, Katherine L. Hunting, Mustafa Dosemeci, Sonja I. Berndt, Paul Brennan, Wong-Ho Chow, and Lee E. Moore. CANCER; Published Online: March 8, 2010 (DOI: 10.1002/cncr.24939).
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Vitamin D Crucial To Activating Immune Defenses
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Scientists at the University of Copenhagen have discovered that Vitamin D is crucial to activating our immune defenses and that without sufficient intake of the vitamin, the killer cells of the immune system – T cells - will not be able to react to and fight off serious infections in the body.
For T cells to detect and kill foreign pathogens such as clumps of bacteria or viruses, the cells must first be 'triggered' into action and 'transform' from inactive and harmless immune cells into killer cells that are primed to seek out and destroy all traces of a foreign pathogen.
The researchers found that the T cells rely on vitamin D in order to activate and they would remain dormant, 'naïve' to the possibility of threat if vitamin D is lacking in the blood.
Chemical Reaction that Enables Activation
In order for the specialized immune cells (T cells) to protect the body from dangerous viruses or bacteria, the T cells must first be exposed to traces of the foreign pathogen. This occurs when they are presented by other immune cells in the body (known as macrophages) with suspicious 'cell fragments' or 'traces' of the pathogen. The T cells then bind to the fragment and divide and multiply into hundreds of identical cells that are all focused on the same pathogen type. The sequence of chemical changes that the T cells undergo enables them to both be 'sensitized to' and able to deliver a targeted immune response.
Professor Carsten Geisler from the Department of International Health, Immunology and Microbiology explains that "when a T cell is exposed to a foreign pathogen, it extends a signaling device or 'antenna' known as a vitamin D receptor, with which it searches for vitamin D. This means that the T cell must have vitamin D or activation of the cell will cease. If the T cells cannot find enough vitamin D in the blood, they won't even begin to mobilize. "
T cells that are successfully activated transform into one of two types of immune cell. They either become killer cells that will attack and destroy all cells carrying traces of a foreign pathogen or they become helper cells that assist the immune system in acquiring "memory". The helper cells send messages to the immune system, passing on knowledge about the pathogen so that the immune system can recognize and remember it at their next encounter. T cells form part of the adaptive immune system, which means that they function by teaching the immune system to recognize and adapt to constantly changing threats.
Activating and Deactivating the Immune System
For the research team, identifying the role of vitamin D in the activation of T cells has been a major breakthrough. "Scientists have known for a long time that vitamin D is important for calcium absorption and the vitamin has also been implicated in diseases such as cancer and multiple sclerosis, but what we didn't realize is how crucial vitamin D is for actually activating the immune system – which we know now. "
The discovery, the scientists believe, provides much needed information about the immune system and will help them regulate the immune response. This is important not only in fighting disease but also in dealing with anti-immune reactions of the body and the rejection of transplanted organs. Active T cells multiply at an explosive rate and can create an inflammatory environment with serious consequences for the body. After organ transplants, e.g. T cells can attack the donor organ as a "foreign invader". In autoimmune disease, hypersensitive T cells mistake fragments of the body's own cells for foreign pathogens, leading to the body launching an attack upon itself.
The research team was also able to track the biochemical sequence of the transformation of an inactive T cell to an active cell, and thus would be able to intervene at several points to modulate the immune response. Inactive or 'naïve' T cells crucially contain neither the vitamin D receptor nor a specific molecule (PLC-gamma1) that would enable the cell to deliver an antigen specific response.
The findings, continues Professor Geisler "could help us to combat infectious diseases and global epidemics. They will be of particular use when developing new vaccines, which work precisely on the basis of both training our immune systems to react and suppressing the body's natural defenses in situations where this is important – as is the case with organ transplants and autoimmune disease."
Most Vitamin D is produced as a natural byproduct of the skin's exposure to sunlight. It can also be found in fish liver oil, eggs and fatty fish such as salmon, herring and mackerel or taken as a dietary supplement. No definitive studies have been carried out for the optimal daily dosage of vitamin D but as a large proportion of the population have very low concentrations of vitamin D in the blood, a number of experts recommend between 25-50mg micrograms a day.
###
The findings will be published in the latest edition of Nature Immunology, (Vitamin D controls T cell antigen receptor signaling and activation of human T cells ) 10.1038/ni.1851, on 07 March
*
Scientists at the University of Copenhagen have discovered that Vitamin D is crucial to activating our immune defenses and that without sufficient intake of the vitamin, the killer cells of the immune system – T cells - will not be able to react to and fight off serious infections in the body.
For T cells to detect and kill foreign pathogens such as clumps of bacteria or viruses, the cells must first be 'triggered' into action and 'transform' from inactive and harmless immune cells into killer cells that are primed to seek out and destroy all traces of a foreign pathogen.
The researchers found that the T cells rely on vitamin D in order to activate and they would remain dormant, 'naïve' to the possibility of threat if vitamin D is lacking in the blood.
Chemical Reaction that Enables Activation
In order for the specialized immune cells (T cells) to protect the body from dangerous viruses or bacteria, the T cells must first be exposed to traces of the foreign pathogen. This occurs when they are presented by other immune cells in the body (known as macrophages) with suspicious 'cell fragments' or 'traces' of the pathogen. The T cells then bind to the fragment and divide and multiply into hundreds of identical cells that are all focused on the same pathogen type. The sequence of chemical changes that the T cells undergo enables them to both be 'sensitized to' and able to deliver a targeted immune response.
Professor Carsten Geisler from the Department of International Health, Immunology and Microbiology explains that "when a T cell is exposed to a foreign pathogen, it extends a signaling device or 'antenna' known as a vitamin D receptor, with which it searches for vitamin D. This means that the T cell must have vitamin D or activation of the cell will cease. If the T cells cannot find enough vitamin D in the blood, they won't even begin to mobilize. "
T cells that are successfully activated transform into one of two types of immune cell. They either become killer cells that will attack and destroy all cells carrying traces of a foreign pathogen or they become helper cells that assist the immune system in acquiring "memory". The helper cells send messages to the immune system, passing on knowledge about the pathogen so that the immune system can recognize and remember it at their next encounter. T cells form part of the adaptive immune system, which means that they function by teaching the immune system to recognize and adapt to constantly changing threats.
Activating and Deactivating the Immune System
For the research team, identifying the role of vitamin D in the activation of T cells has been a major breakthrough. "Scientists have known for a long time that vitamin D is important for calcium absorption and the vitamin has also been implicated in diseases such as cancer and multiple sclerosis, but what we didn't realize is how crucial vitamin D is for actually activating the immune system – which we know now. "
The discovery, the scientists believe, provides much needed information about the immune system and will help them regulate the immune response. This is important not only in fighting disease but also in dealing with anti-immune reactions of the body and the rejection of transplanted organs. Active T cells multiply at an explosive rate and can create an inflammatory environment with serious consequences for the body. After organ transplants, e.g. T cells can attack the donor organ as a "foreign invader". In autoimmune disease, hypersensitive T cells mistake fragments of the body's own cells for foreign pathogens, leading to the body launching an attack upon itself.
The research team was also able to track the biochemical sequence of the transformation of an inactive T cell to an active cell, and thus would be able to intervene at several points to modulate the immune response. Inactive or 'naïve' T cells crucially contain neither the vitamin D receptor nor a specific molecule (PLC-gamma1) that would enable the cell to deliver an antigen specific response.
The findings, continues Professor Geisler "could help us to combat infectious diseases and global epidemics. They will be of particular use when developing new vaccines, which work precisely on the basis of both training our immune systems to react and suppressing the body's natural defenses in situations where this is important – as is the case with organ transplants and autoimmune disease."
Most Vitamin D is produced as a natural byproduct of the skin's exposure to sunlight. It can also be found in fish liver oil, eggs and fatty fish such as salmon, herring and mackerel or taken as a dietary supplement. No definitive studies have been carried out for the optimal daily dosage of vitamin D but as a large proportion of the population have very low concentrations of vitamin D in the blood, a number of experts recommend between 25-50mg micrograms a day.
###
The findings will be published in the latest edition of Nature Immunology, (Vitamin D controls T cell antigen receptor signaling and activation of human T cells ) 10.1038/ni.1851, on 07 March
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