Thursday, July 30, 2009
Reducing salt intake can lower blood pressure
Studies provide no proof of positive influence on late complications from essential hypertension
Adults who use less salt in their diet can experience a slight reduction in their blood pressure in the medium term. However, whether in the long term this can also reduce the risk of late complications in people with sustained high blood pressure, otherwise known as essential hypertension, and whether in the long term their anti-hypertensive medication can be reduced remains unresolved. This is the conclusion of the Institute for Quality and Efficiency in Health Care (IQWiG) in its final report published in the form of a rapid report on 20 July 2009.
This rapid report is part of a package commissioned by the Federal Joint Committee (G-BA), in which the benefit of various non-drug treatment strategies for high blood pressure are to be assessed. Stress management and more physical activity are also included, as well as giving up smoking and cutting down alcohol consumption. IQWiG has already completed a report on the effect of weight reduction on blood pressure.
Assessment was based on secondary literature
IQWiG's benefit assessments are generally based on systematic searches and analysis of clinical trials, in other words, primary literature. However, this rapid report was prepared on the basis of secondary literature. In principle, this can be done - and is included in IQWiG's General Methods - if current, high quality systematic reviews are already available on a given topic. This was the case with reducing salt intake in hypertension, as IQWiG's preliminary search revealed.
IQWiG searched for systematic reviews (these basically provide an analysis of studies in summary) that compared the following patients with hypertension: an intervention group, which was to follow a low-salt diet over a long period, versus a control group, which either did not have this target or whose salt reduction was not so great as in the intervention group. The minimum duration of the studies had to be 4 weeks. In order not to overlook any current and potentially relevant studies, IQWiG also conducted an update search of recently published primary studies.
IQWiG was able to include in its assessment 7 reviews, in which the results of between 520 and 3391 participants from a total of 62 randomized controlled trials were analysed together.
No conclusions on cardiovascular disease or mortality possible
IQWiG found that no conclusions on late complications could be drawn from the available data. The reason for this is that none of the studies had the primary goal of investigating the effects of a low-salt diet on cardiovascular disease or all-cause mortality. Moreover, most of the studies were only of a few months' duration and had low numbers of participants, which meant that possible differences in late complications might not have been detected with certainty.
Uncertainty whether the reduction in blood pressure is sustainable
However, the investigations consistently show that a reduction in salt intake can assist in lowering blood pressure: over a period of up to one year, there was a mean drop of 3.6 to 8 mmHg in systolic values and a mean drop of approximately 2 to 3 mmHg in diastolic values. This applied primarily to patients who did not take any additional anti-hypertensive drugs.
The sustainability of this effect, however, remains unclear. The authors of at least one review report that the observed advantage disappears when the analysis is restricted to studies of a longer duration (at least 6 months).
None of the reviews solely considered patients who were simultaneously taking anti-hypertensive drugs or separately analysed data for participants on concomitant medication. The additional blood pressure-lowering effect of a low-salt diet in these patients is therefore uncertain.
Basically, it is still not known whether people with essential hypertension can reduce their drug dosage through less salt intake.
Freshly crushed garlic better for heart than processed
A new study reports what scientists term the first scientific evidence that freshly crushed garlic has more potent heart-healthy effects than dried garlic. Scheduled for the Aug. 12 issue of the Journal of Agricultural and Food Chemistry, it also challenges the widespread belief that most of garlic's benefits are due to its rich array of antioxidants. Instead, garlic's heart-healthy effects seem to result mainly from hydrogen sulfide, a chemical signaling substance that forms after garlic is cut or crushed and relaxes blood vessels when eaten.
In the study, Dipak K. Das and colleagues point out that raw, crushed garlic generates hydrogen sulfide through a chemical reaction. Although best known as the stuff that gives rotten eggs their distinctive odor, hydrogen sulfide also acts as a chemical messenger in the body, relaxing blood vessels and allowing more blood to pass through. Processed and cooked garlic, however, loses its ability to generate hydrogen sulfide.
The scientists gave freshly crushed garlic and processed garlic to two groups of lab rats, and then studied how well the animals' hearts recovered from simulated heart attacks. "Both crushed and processed garlic reduced damage from lack of oxygen, but the fresh garlic group had a significantly greater effect on restoring good blood flow in the aorta and increased pressure in the left ventricle of the heart," Das said.
Exercise Benefits Women Even More Than Men
Health benefits of physical activity more pronounced in women
Many experimental studies have found that physical exercise can improve cholesterol levels and subsequently decrease the risks of cardiovascular disease; however, few of these studies have included enough participant diversity to provide ethnic breakdowns. Now, a long-term study of over 8,700 middle-aged men and women provides race- and gender- specific data on the cholesterol effects of physical activity, with the interesting result that women, particularly African-American women, experience greater benefits as a result of exercise than men.
The analysis of this large Atherosclerosis Risk in Communities (ARIC) Study, which appears in the August issue of Journal of Lipid Research, was carried out by Keri Monda and colleagues at North Carolina and Baylor. They found that over a 12 year period, all individuals who increased their exercise by about 180 metabolic units per week (equivalent to an additional hour of mild or 30 minutes of moderate activity per week) displayed decreased levels of triglycerides and increased levels of the "good" HDL cholesterol. However, statistically significant decreases in the "bad" LDL cholesterol were only observed in women, with particularly strong effects in menopausal women and African-American women. And total cholesterol levels were only significantly decreased in African-American women.
The authors speculate that these novel differences may arise from hormonal differences between the sexes, especially considering the extra effects seen post-menopause. The racial differences observed may stem from genetic variations that require further exploration.
The authors do also note that their exercise data was assessed by questionnaire and this was non-scientific, though the particular methodology used has been extremely reliable in other studies. They also note that all evaluated participants were healthy, so these results cannot be generalized to individuals with diabetes or those on cholesterol-lowering medications.
Many experimental studies have found that physical exercise can improve cholesterol levels and subsequently decrease the risks of cardiovascular disease; however, few of these studies have included enough participant diversity to provide ethnic breakdowns. Now, a long-term study of over 8,700 middle-aged men and women provides race- and gender- specific data on the cholesterol effects of physical activity, with the interesting result that women, particularly African-American women, experience greater benefits as a result of exercise than men.
The analysis of this large Atherosclerosis Risk in Communities (ARIC) Study, which appears in the August issue of Journal of Lipid Research, was carried out by Keri Monda and colleagues at North Carolina and Baylor. They found that over a 12 year period, all individuals who increased their exercise by about 180 metabolic units per week (equivalent to an additional hour of mild or 30 minutes of moderate activity per week) displayed decreased levels of triglycerides and increased levels of the "good" HDL cholesterol. However, statistically significant decreases in the "bad" LDL cholesterol were only observed in women, with particularly strong effects in menopausal women and African-American women. And total cholesterol levels were only significantly decreased in African-American women.
The authors speculate that these novel differences may arise from hormonal differences between the sexes, especially considering the extra effects seen post-menopause. The racial differences observed may stem from genetic variations that require further exploration.
The authors do also note that their exercise data was assessed by questionnaire and this was non-scientific, though the particular methodology used has been extremely reliable in other studies. They also note that all evaluated participants were healthy, so these results cannot be generalized to individuals with diabetes or those on cholesterol-lowering medications.
Health Benefits of Zinc Explained
New report in the Journal of Leukocyte Biology suggests that zinc activates a key protein on T cells needed to fight infections
Everyone knows that vitamins "from A to zinc" are important for good health. Now, a new research study in the August 2009 print issue of the Journal of Leukocyte Biology (http://www.jleukbio.org) suggests that zinc may be pointing the way to new therapeutic targets for fighting infections. Specifically, scientists from Florida found that zinc not only supports healthy immune function, but increases activation of the cells (T cells) responsible for destroying viruses and bacteria.
"It has been shown that zinc supplementation significantly reduces the duration and severity of childhood diarrhea, lower respiratory infections, and incidence of malaria in zinc-deficient children," said report co-author, Robert Cousins, Ph.D., who also is the director of the Center for Nutritional Sciences within the Food Science and Human Nutrition Department at the University of Florida. "Age-related declines in immune function have also been related to zinc deficiency in the elderly."
Scientists administered either a zinc supplement or a placebo to healthy volunteers to assess the effects of zinc on T cell activation. After isolating the T cells from the blood, scientists then simulated infection in laboratory conditions. Results showed that T cells taken from the zinc-supplemented group had higher activation than those from the placebo group. Specifically, cell activation stimulated the zinc transporter in T cells called "ZIP8," which transports stored zinc into the cell cytoplasm where it then alters the expression of a T cell protein in a way needed to fight infections.
"As the debate over zinc supplementation in healthy individuals continues," said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology, "studies like this help shed light on how zinc may enhance the ability of our immune systems to fight off foreign invaders. Equally important, this work points toward new possible targets for entirely new drugs to help augment immune function and prevent or stop infections that might be resistant to traditional antibiotics."
Everyone knows that vitamins "from A to zinc" are important for good health. Now, a new research study in the August 2009 print issue of the Journal of Leukocyte Biology (http://www.jleukbio.org) suggests that zinc may be pointing the way to new therapeutic targets for fighting infections. Specifically, scientists from Florida found that zinc not only supports healthy immune function, but increases activation of the cells (T cells) responsible for destroying viruses and bacteria.
"It has been shown that zinc supplementation significantly reduces the duration and severity of childhood diarrhea, lower respiratory infections, and incidence of malaria in zinc-deficient children," said report co-author, Robert Cousins, Ph.D., who also is the director of the Center for Nutritional Sciences within the Food Science and Human Nutrition Department at the University of Florida. "Age-related declines in immune function have also been related to zinc deficiency in the elderly."
Scientists administered either a zinc supplement or a placebo to healthy volunteers to assess the effects of zinc on T cell activation. After isolating the T cells from the blood, scientists then simulated infection in laboratory conditions. Results showed that T cells taken from the zinc-supplemented group had higher activation than those from the placebo group. Specifically, cell activation stimulated the zinc transporter in T cells called "ZIP8," which transports stored zinc into the cell cytoplasm where it then alters the expression of a T cell protein in a way needed to fight infections.
"As the debate over zinc supplementation in healthy individuals continues," said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology, "studies like this help shed light on how zinc may enhance the ability of our immune systems to fight off foreign invaders. Equally important, this work points toward new possible targets for entirely new drugs to help augment immune function and prevent or stop infections that might be resistant to traditional antibiotics."
The secret of red wine's health benefits
New research in the FASEB Journal shows how resveratrol works as an effective therapy for life-threatening inflammation
Scientists from Scotland and Singapore have unraveled a mystery that has perplexed scientists since red wine was first discovered to have health benefits: how does resveratrol control inflammation? New research published in the August 2009 print issue of The FASEB Journal (http://www.fasebj.org), not only explains resveratrol's one-two punch on inflammation, but also show how it—or a derivative—can be used to treat potentially deadly inflammatory disease, such as appendicitis, peritonitis, and systemic sepsis.
"Strong acute inflammatory diseases such as sepsis are very difficult to treat and many die every day due to lack of treatment," said Alirio Melendez, senior lecturer on the faculty of medicine at Glasgow Biomedical Research Centre in Scotland and one of the researchers involved in the work. "Moreover, many survivors of sepsis develop a very low quality of life due to the damage that inflammation causes to several internal organs. The ultimate goal of our study was to identify a potential novel therapy to help in the treatment of strong acute inflammatory diseases."
In this study, researchers administered an inflammatory agent to two groups of mice. One group was pretreated with resveratrol and the other group was not. The mice that were not pretreated with resveratrol experienced a strong inflammatory response, simulating disease in humans, while the group pretreated with resveratrol was protected from the inflammation. The scientists then examined the tissues of the mice to determine exactly how resveratrol was able to protect the mice from inflammation. They found that resveratrol used a one-two punch to stop inflammation in the mice by preventing the body from creating two different molecules known to trigger inflammation, sphingosine kinase and phospholipase D. This finding suggests that resveratrol may be harnessable as a treatment for inflammatory diseases and may also lead to entirely new resveratrol-based drugs that are even more effective.
"The therapeutic potential of red wine has been bottled up for thousands of years," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal, "and now that scientists have uncorked its secrets, they find that studies of how resveratrol works can lead to new treatments for life-threatening inflammation."
Scientists from Scotland and Singapore have unraveled a mystery that has perplexed scientists since red wine was first discovered to have health benefits: how does resveratrol control inflammation? New research published in the August 2009 print issue of The FASEB Journal (http://www.fasebj.org), not only explains resveratrol's one-two punch on inflammation, but also show how it—or a derivative—can be used to treat potentially deadly inflammatory disease, such as appendicitis, peritonitis, and systemic sepsis.
"Strong acute inflammatory diseases such as sepsis are very difficult to treat and many die every day due to lack of treatment," said Alirio Melendez, senior lecturer on the faculty of medicine at Glasgow Biomedical Research Centre in Scotland and one of the researchers involved in the work. "Moreover, many survivors of sepsis develop a very low quality of life due to the damage that inflammation causes to several internal organs. The ultimate goal of our study was to identify a potential novel therapy to help in the treatment of strong acute inflammatory diseases."
In this study, researchers administered an inflammatory agent to two groups of mice. One group was pretreated with resveratrol and the other group was not. The mice that were not pretreated with resveratrol experienced a strong inflammatory response, simulating disease in humans, while the group pretreated with resveratrol was protected from the inflammation. The scientists then examined the tissues of the mice to determine exactly how resveratrol was able to protect the mice from inflammation. They found that resveratrol used a one-two punch to stop inflammation in the mice by preventing the body from creating two different molecules known to trigger inflammation, sphingosine kinase and phospholipase D. This finding suggests that resveratrol may be harnessable as a treatment for inflammatory diseases and may also lead to entirely new resveratrol-based drugs that are even more effective.
"The therapeutic potential of red wine has been bottled up for thousands of years," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal, "and now that scientists have uncorked its secrets, they find that studies of how resveratrol works can lead to new treatments for life-threatening inflammation."
Tuesday, July 28, 2009
Vitamin D and Prostate Cancer
Vitamin D may turn out to be a ray of hope for men with prostate cancer. Laboratory and population-based research suggest that adequate levels of vitamin D reduce the risk of developing prostate cancer and may help suppress the growth and spread of prostate cancer cells in men who already have it. A significant proportion of older men have suboptimal levels of vitamin D, especially during the winter and spring months. But boosting your vitamin D levels isn't difficult.
Vitamin D has two main forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D2 is found in fortified milk and dietary supplements. Vitamin D3 is created within the skin after exposure to sunlight. In the body, vitamins D2 and D3 must be converted in the liver and kidneys into 1,25 dihydroxyvitamin D, the biologically active form. 1,25 dihydroxyvitamin D is required for several important body functions, including the absorption of calcium and phosphorus. It also helps promote bone mineralization, the process by which new bone is created as old bone is broken down.
In addition, vitamin D is believed to help maintain a strong immune system and to regulate cell growth, differentiation (the process whereby new cells develop into distinct types of cells), and apoptosis (the programmed cell death that keeps cell proliferation in check). Out-of-control cell proliferation is the hallmark of cancer.
Studies over the years have pointed to an association between geographic location and the risk of dying of certain diseases. For example, people who live in more southerly latitudes (and who receive year-round sunshine) appear to have a lower risk of dying of cardiovascular disease, diabetes, and some cancers, such as colon and breast, than do those who live in northern latitudes. Researchers suspect that the higher sun exposure, which creates more vitamin D in the skin, may be responsible.
Sun exposure also appears to influence a man's risk of developing prostate cancer. Research suggests that men who were born in sun-drenched areas of the United States are about half as likely to develop prostate cancer later in life as men born in an area with low sun exposure. In the study, higher recreational sun exposure in adulthood also cut men's risk of fatal prostate cancer in half.
The sun exposure research is bolstered by studies showing a link between blood levels of vitamin D and prostate cancer. For example, the long-running Physicians' Health Study found that more than two thirds of the nearly 15,000 study participants had inadequate blood levels of vitamin D in the winter and spring. Among men who developed prostate cancer, those with low levels of vitamin D were more likely to have an aggressive form of the disease. This was especially true among men age 65 or older. When the researchers examined a gene involved in converting vitamins D2 and D3 into the active form, they found that a specific variant of the gene increased susceptibility to developing aggressive prostate cancer when blood levels of vitamin D are low.
How Much Vitamin D? The answer is not clear. According to the Institute of Medicine (IOM), an adequate intake of vitamin D is 200 IU per day for people age 50 or younger. Older individuals need more vitamin D because their skin is less efficient in synthesizing the vitamin, and their kidneys are less able to convert it to the active form. Thus, the IOM's recommended daily intake of vitamin D is 400 IU for those age 51 to 70 and 600 IU for people age 71 or older.
According to the National Institutes of Health Office of Dietary Supplements, people at risk are age 50 or over; live in New England or farther north; are homebound; have darker skin; have medical conditions that inhibit fat absorption, such as liver disease or Crohn's disease; or have had part or all of their stomach or intestines removed.
Sources of Vitamin D. It can be difficult to get all of the vitamin D you need through your diet. Vitamin supplements are another option. Over-the-counter multivitamins typically contain 200 to 400 IU of vitamin D, but you can buy supplements that contain higher amounts. When choosing a supplement, look for one that contains vitamin D3, which is more effective than vitamin D2.
The Bottom Line: Even though it's not yet proven that increasing your vitamin D intake will decrease your risk of prostate cancer, there's clearly an association between the two. If you're young, healthy and fair skinned and live in a sunny, more southerly locale, you should be able to satisfy much of your vitamin D requirement with brief sun exposure (10 to 15 minutes without sunscreen on a clear day) two to three times per week.
But if you're age 50 or over or are otherwise at increased risk for vitamin D deficiency, sun exposure probably won't be enough to boost your intake. Also eat more vitamin D-rich foods and take a daily supplement so that your total daily intake is about 1,000 IU. Also, after your 15-minute dose of sunshine, don't forget to apply a sunscreen with an SPF of at least 15 to reduce your risk of developing skin cancer.
Vitamin D has two main forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D2 is found in fortified milk and dietary supplements. Vitamin D3 is created within the skin after exposure to sunlight. In the body, vitamins D2 and D3 must be converted in the liver and kidneys into 1,25 dihydroxyvitamin D, the biologically active form. 1,25 dihydroxyvitamin D is required for several important body functions, including the absorption of calcium and phosphorus. It also helps promote bone mineralization, the process by which new bone is created as old bone is broken down.
In addition, vitamin D is believed to help maintain a strong immune system and to regulate cell growth, differentiation (the process whereby new cells develop into distinct types of cells), and apoptosis (the programmed cell death that keeps cell proliferation in check). Out-of-control cell proliferation is the hallmark of cancer.
Studies over the years have pointed to an association between geographic location and the risk of dying of certain diseases. For example, people who live in more southerly latitudes (and who receive year-round sunshine) appear to have a lower risk of dying of cardiovascular disease, diabetes, and some cancers, such as colon and breast, than do those who live in northern latitudes. Researchers suspect that the higher sun exposure, which creates more vitamin D in the skin, may be responsible.
Sun exposure also appears to influence a man's risk of developing prostate cancer. Research suggests that men who were born in sun-drenched areas of the United States are about half as likely to develop prostate cancer later in life as men born in an area with low sun exposure. In the study, higher recreational sun exposure in adulthood also cut men's risk of fatal prostate cancer in half.
The sun exposure research is bolstered by studies showing a link between blood levels of vitamin D and prostate cancer. For example, the long-running Physicians' Health Study found that more than two thirds of the nearly 15,000 study participants had inadequate blood levels of vitamin D in the winter and spring. Among men who developed prostate cancer, those with low levels of vitamin D were more likely to have an aggressive form of the disease. This was especially true among men age 65 or older. When the researchers examined a gene involved in converting vitamins D2 and D3 into the active form, they found that a specific variant of the gene increased susceptibility to developing aggressive prostate cancer when blood levels of vitamin D are low.
How Much Vitamin D? The answer is not clear. According to the Institute of Medicine (IOM), an adequate intake of vitamin D is 200 IU per day for people age 50 or younger. Older individuals need more vitamin D because their skin is less efficient in synthesizing the vitamin, and their kidneys are less able to convert it to the active form. Thus, the IOM's recommended daily intake of vitamin D is 400 IU for those age 51 to 70 and 600 IU for people age 71 or older.
According to the National Institutes of Health Office of Dietary Supplements, people at risk are age 50 or over; live in New England or farther north; are homebound; have darker skin; have medical conditions that inhibit fat absorption, such as liver disease or Crohn's disease; or have had part or all of their stomach or intestines removed.
Sources of Vitamin D. It can be difficult to get all of the vitamin D you need through your diet. Vitamin supplements are another option. Over-the-counter multivitamins typically contain 200 to 400 IU of vitamin D, but you can buy supplements that contain higher amounts. When choosing a supplement, look for one that contains vitamin D3, which is more effective than vitamin D2.
The Bottom Line: Even though it's not yet proven that increasing your vitamin D intake will decrease your risk of prostate cancer, there's clearly an association between the two. If you're young, healthy and fair skinned and live in a sunny, more southerly locale, you should be able to satisfy much of your vitamin D requirement with brief sun exposure (10 to 15 minutes without sunscreen on a clear day) two to three times per week.
But if you're age 50 or over or are otherwise at increased risk for vitamin D deficiency, sun exposure probably won't be enough to boost your intake. Also eat more vitamin D-rich foods and take a daily supplement so that your total daily intake is about 1,000 IU. Also, after your 15-minute dose of sunshine, don't forget to apply a sunscreen with an SPF of at least 15 to reduce your risk of developing skin cancer.
Friday, July 24, 2009
Drink Milk For Longer Life
Drinking milk can lessen the chances of dying from illnesses such as coronary heart disease (CHD) and stroke by up to 15-20%, according to research undertaken by the Universities of Reading, Cardiff and Bristol.
In recent times milk has often been portrayed by the media as an unhealthy food. The study, led by Professor Peter Elwood (Cardiff University) together with Professor Ian Givens from the University of Reading’s Food Chain and Health Research Theme, aimed to establish whether the health benefits of drinking milk outweigh any dangers that lie in its consumption.
Importantly, this is the first time that disease risk associated with drinking milk has been looked at in relation to the number of deaths which the diseases are responsible for.
The review brought together published evidence from 324 studies of milk consumption as predictors of coronary heart disease (CHD), stroke and, diabetes. Data on milk consumption and cancer were based on the recent World Cancer Research Fund report. The outcomes were then compared with current death rates from these diseases.
Professor Givens explained: “While growth and bone health are of great importance to health and function, it is the effects of milk and dairy consumption on chronic disease that are of the greatest relevance to reduced morbidity and survival. Our review made it possible to assess overall whether increased milk consumption provides a survival advantage or not. We believe it does.
“Our findings clearly show that when the numbers of deaths from CHD, stroke and colo-rectal cancer were taken into account, there is strong evidence of an overall reduction in the risk of dying from these chronic diseases due to milk consumption. We certainly found no evidence that drinking milk might increase the risk of developing any condition, with the exception of prostate cancer. Put together, there is convincing overall evidence that milk consumption is associated with an increase in survival in Western communities.”
The reviewers also believe that increased milk consumption is likely to reduce health care costs substantially due to reduced chronic disease and associated morbidity.
In recent times milk has often been portrayed by the media as an unhealthy food. The study, led by Professor Peter Elwood (Cardiff University) together with Professor Ian Givens from the University of Reading’s Food Chain and Health Research Theme, aimed to establish whether the health benefits of drinking milk outweigh any dangers that lie in its consumption.
Importantly, this is the first time that disease risk associated with drinking milk has been looked at in relation to the number of deaths which the diseases are responsible for.
The review brought together published evidence from 324 studies of milk consumption as predictors of coronary heart disease (CHD), stroke and, diabetes. Data on milk consumption and cancer were based on the recent World Cancer Research Fund report. The outcomes were then compared with current death rates from these diseases.
Professor Givens explained: “While growth and bone health are of great importance to health and function, it is the effects of milk and dairy consumption on chronic disease that are of the greatest relevance to reduced morbidity and survival. Our review made it possible to assess overall whether increased milk consumption provides a survival advantage or not. We believe it does.
“Our findings clearly show that when the numbers of deaths from CHD, stroke and colo-rectal cancer were taken into account, there is strong evidence of an overall reduction in the risk of dying from these chronic diseases due to milk consumption. We certainly found no evidence that drinking milk might increase the risk of developing any condition, with the exception of prostate cancer. Put together, there is convincing overall evidence that milk consumption is associated with an increase in survival in Western communities.”
The reviewers also believe that increased milk consumption is likely to reduce health care costs substantially due to reduced chronic disease and associated morbidity.
Tuesday, July 21, 2009
Healthy lifestyle = less high blood pressure problems
Adopting low-risk dietary and lifestyle factors related to lower incidence of high blood pressure
Adherence to modifiable lifestyle and dietary factors including maintaining normal weight, daily vigorous exercise, eating a diet high in fruits, vegetables, low-fat dairy products and low in sodium and taking a folic acid supplement was associated with a significantly lower incidence of self-reported hypertension among women, according to a study in the July 22/29 issue of JAMA.
Hypertension (high blood pressure) contributes to more excess deaths in women than any other preventable factor. "Pharmacological treatment of established hypertension has proven benefits, yet these efforts are costly, require medical intervention, and have adverse effects," the authors write. "Primary prevention of hypertension, therefore, would have major positive public health ramifications." While several modifiable risk factors have been identified, the proportion of patients with new-onset hypertension that could conceivably be prevented by modification of a combination of lifestyle factors has not previously been evaluated.
John P. Forman, M.D., M.Sc., of Brigham and Women's Hospital and Harvard Medical School, Boston, and colleagues examined the association between combinations of low-risk lifestyle factors and the risk of developing hypertension. The study included 83,882 adult women (age 27 to 44 years) in the second Nurses' Health Study who did not have hypertension, cardiovascular disease, diabetes, or cancer in 1991, and who had normal reported blood pressure (defined as systolic blood pressure of ≤120 mm Hg and diastolic blood pressure of ≤80 mm Hg). There was follow-up for new hypertension for 14 years through 2005.
Six modifiable lifestyle and dietary factors for hypertension were identified and included a body mass index (BMI) of less than 25; a daily average of 30 minutes of vigorous exercise; a high score on the Dietary Approaches to Stop Hypertension (DASH) diet based on responses to a food frequency questionnaire; modest alcohol intake; use of nonnarcotic analgesics less than once per week; and intake of 400 μg/d or more of supplemental folic acid. A DASH score was determined based on high intake of fruits, vegetables, nuts and legumes, low-fat dairy products, and whole grains, and low intake of sodium, sweetened beverages, and red and processed meats.
The association between combinations of 3 (normal BMI, daily vigorous exercise, and DASH-style diet), 4 (3 low-risk factors plus modest alcohol intake), 5 (4 low-risk factors plus avoidance of nonnarcotic analgesics), and 6 (folic acid supplementation ≥400 g/d) low-risk factors and the risk of developing hypertension was analyzed.
During the follow-up, a total of 12,319 new cases of hypertension were reported. All 6 modifiable risk factors were independently associated with the risk of developing hypertension during follow-up after also adjusting for age, race, family history of hypertension, smoking status, and use of oral contraceptives. For women who had all 6 low-risk factors (0.3 percent of the population), they had about an 80 percent lower risk of developing high blood pressure.
The hypothetical population attributable risks (PARs; an estimate of the percentage of new hypertension cases occurring in this population that hypothetically could have been prevented if all women had been in the low-risk group) was 78 percent for women who lacked these low-risk factors. The PARs were 72 percent for 5 low-risk factors (0.8 percent of the population); 58 percent for 4 low-risk factors (1.6 percent of the population); and 53 percent for 3 low-risk factors (3.1 percent of the population). Body mass index alone was the most powerful predictor of hypertension, with a BMI of 25 or greater having an adjusted PAR of 40 percent compared with a BMI of less than 25.
The authors add that their "data indicate that adherence to a combination of low-risk lifestyle factors could have the potential to prevent the majority of new-onset hypertension in young women irrespective of family history of hypertension and irrespective of oral contraceptive use. The former conclusion is particularly poignant given that some women may mistakenly believe that their parental history signifies that their own development of hypertension may be unavoidable; rather, these women may conceivably at least delay onset of hypertension by reducing their risk factors."
"In conclusion, adherence to low-risk dietary and lifestyle factors was associated with significant reductions in the incidence of self-reported hypertension and could have the potential to prevent a large proportion of new-onset hypertension occurring among young women. Prevention of hypertension would, in turn, have major public health benefits."
Adherence to modifiable lifestyle and dietary factors including maintaining normal weight, daily vigorous exercise, eating a diet high in fruits, vegetables, low-fat dairy products and low in sodium and taking a folic acid supplement was associated with a significantly lower incidence of self-reported hypertension among women, according to a study in the July 22/29 issue of JAMA.
Hypertension (high blood pressure) contributes to more excess deaths in women than any other preventable factor. "Pharmacological treatment of established hypertension has proven benefits, yet these efforts are costly, require medical intervention, and have adverse effects," the authors write. "Primary prevention of hypertension, therefore, would have major positive public health ramifications." While several modifiable risk factors have been identified, the proportion of patients with new-onset hypertension that could conceivably be prevented by modification of a combination of lifestyle factors has not previously been evaluated.
John P. Forman, M.D., M.Sc., of Brigham and Women's Hospital and Harvard Medical School, Boston, and colleagues examined the association between combinations of low-risk lifestyle factors and the risk of developing hypertension. The study included 83,882 adult women (age 27 to 44 years) in the second Nurses' Health Study who did not have hypertension, cardiovascular disease, diabetes, or cancer in 1991, and who had normal reported blood pressure (defined as systolic blood pressure of ≤120 mm Hg and diastolic blood pressure of ≤80 mm Hg). There was follow-up for new hypertension for 14 years through 2005.
Six modifiable lifestyle and dietary factors for hypertension were identified and included a body mass index (BMI) of less than 25; a daily average of 30 minutes of vigorous exercise; a high score on the Dietary Approaches to Stop Hypertension (DASH) diet based on responses to a food frequency questionnaire; modest alcohol intake; use of nonnarcotic analgesics less than once per week; and intake of 400 μg/d or more of supplemental folic acid. A DASH score was determined based on high intake of fruits, vegetables, nuts and legumes, low-fat dairy products, and whole grains, and low intake of sodium, sweetened beverages, and red and processed meats.
The association between combinations of 3 (normal BMI, daily vigorous exercise, and DASH-style diet), 4 (3 low-risk factors plus modest alcohol intake), 5 (4 low-risk factors plus avoidance of nonnarcotic analgesics), and 6 (folic acid supplementation ≥400 g/d) low-risk factors and the risk of developing hypertension was analyzed.
During the follow-up, a total of 12,319 new cases of hypertension were reported. All 6 modifiable risk factors were independently associated with the risk of developing hypertension during follow-up after also adjusting for age, race, family history of hypertension, smoking status, and use of oral contraceptives. For women who had all 6 low-risk factors (0.3 percent of the population), they had about an 80 percent lower risk of developing high blood pressure.
The hypothetical population attributable risks (PARs; an estimate of the percentage of new hypertension cases occurring in this population that hypothetically could have been prevented if all women had been in the low-risk group) was 78 percent for women who lacked these low-risk factors. The PARs were 72 percent for 5 low-risk factors (0.8 percent of the population); 58 percent for 4 low-risk factors (1.6 percent of the population); and 53 percent for 3 low-risk factors (3.1 percent of the population). Body mass index alone was the most powerful predictor of hypertension, with a BMI of 25 or greater having an adjusted PAR of 40 percent compared with a BMI of less than 25.
The authors add that their "data indicate that adherence to a combination of low-risk lifestyle factors could have the potential to prevent the majority of new-onset hypertension in young women irrespective of family history of hypertension and irrespective of oral contraceptive use. The former conclusion is particularly poignant given that some women may mistakenly believe that their parental history signifies that their own development of hypertension may be unavoidable; rather, these women may conceivably at least delay onset of hypertension by reducing their risk factors."
"In conclusion, adherence to low-risk dietary and lifestyle factors was associated with significant reductions in the incidence of self-reported hypertension and could have the potential to prevent a large proportion of new-onset hypertension occurring among young women. Prevention of hypertension would, in turn, have major public health benefits."
Healthy lifestyle = reduced risk of heart failure
Men who exercised regularly, drank moderately, did not smoke, who were not overweight and had a diet that included cereal and fruits and vegetables had a lower lifetime risk of heart failure, according to a study in the July 22/29 issue of JAMA.
With an annual incidence of 550,000, heart failure remains a major public health issue and is the leading cause of hospitalization among older adults in the United States. Despite improved medical and surgical management, death after onset of heart failure remains high, ranging from 20 percent to 50 percent. The lifetime risk of heart failure at age 40 years is approximately 1 in 5 in the general population; however, it has been unclear whether adherence to healthy lifestyle factors, such as regular exercise and not smoking, could lead to a reduction in lifetime risk of heart failure, according to background information in the article. "A demonstration of beneficial influence of healthy lifestyle habits on the lifetime risk has potential clinical and public health implications."
Luc Djoussé, M.D., Sc.D., M.P.H., of Brigham and Women's Hospital, Harvard Medical School and Boston Veterans Affairs Healthcare System, Boston, and colleagues assessed the association between modifiable lifestyle factors and the remaining lifetime risk of heart failure in a large group of men. The study included data from 20,900 men (average age at the start of the study, 53.6 years) from the Physicians' Health Study I (1982-2008) who were apparently healthy at baseline. Six modifiable lifestyle factors were assessed: body weight, smoking, exercise, alcohol intake, consumption of breakfast cereals and consumption of fruits and vegetables.
During an average follow-up of 22.4 years, 1,200 new cases of heart failure (5.7 percent) and 4,999 confirmed deaths (23.9 percent) occurred in the study. Compared with participants adhering to no healthy lifestyle factors, those adhering to 4 or more factors tended to be older and had a lower prevalence of hypertension and diabetes mellitus. Analysis indicated that overall, the lifetime risk of heart failure was 13.8 percent at age 40 years and remained constant through age 70; at age 80 years, the lifetime risk for heart failure was 10.6 percent. The remaining lifetime risk of heart failure was approximately 2 percent to 4 percent higher in men with hypertension than in those without hypertension.
The researchers found that normal body weight, never smoking, regular exercise, moderate alcohol intake, and consumption of breakfast cereal and fruits and vegetables were individually associated with a lower lifetime risk of heart failure compared to a corresponding undesirable behavior. There was an inverse and graded association between the number of healthy lifestyle factors and lifetime risk of heart failure. "For example, the lifetime risk for heart failure was approximately 1 in 5 (21.2 percent) in men adhering to none of the desirable lifestyle factors, compared to 1 in 10 (10.1 percent) in those adhering to 4 or more healthy lifestyle factors," the authors write.
When restricted to body weight, smoking, and exercise, the association between lifestyle factors and lifetime risk of heart failure persisted in the overall population as well as in men with and without hypertension.
"Our estimate of lifetime risk of heart failure could help public health officials allocate resources for the prevention and management of this condition. Our findings of a low lifetime risk in men who adhere to modifiable lifestyle factors emphasize the need for incorporation of these behaviors in prevention strategies against heart failure at both the individual and the population level," the authors write.
With an annual incidence of 550,000, heart failure remains a major public health issue and is the leading cause of hospitalization among older adults in the United States. Despite improved medical and surgical management, death after onset of heart failure remains high, ranging from 20 percent to 50 percent. The lifetime risk of heart failure at age 40 years is approximately 1 in 5 in the general population; however, it has been unclear whether adherence to healthy lifestyle factors, such as regular exercise and not smoking, could lead to a reduction in lifetime risk of heart failure, according to background information in the article. "A demonstration of beneficial influence of healthy lifestyle habits on the lifetime risk has potential clinical and public health implications."
Luc Djoussé, M.D., Sc.D., M.P.H., of Brigham and Women's Hospital, Harvard Medical School and Boston Veterans Affairs Healthcare System, Boston, and colleagues assessed the association between modifiable lifestyle factors and the remaining lifetime risk of heart failure in a large group of men. The study included data from 20,900 men (average age at the start of the study, 53.6 years) from the Physicians' Health Study I (1982-2008) who were apparently healthy at baseline. Six modifiable lifestyle factors were assessed: body weight, smoking, exercise, alcohol intake, consumption of breakfast cereals and consumption of fruits and vegetables.
During an average follow-up of 22.4 years, 1,200 new cases of heart failure (5.7 percent) and 4,999 confirmed deaths (23.9 percent) occurred in the study. Compared with participants adhering to no healthy lifestyle factors, those adhering to 4 or more factors tended to be older and had a lower prevalence of hypertension and diabetes mellitus. Analysis indicated that overall, the lifetime risk of heart failure was 13.8 percent at age 40 years and remained constant through age 70; at age 80 years, the lifetime risk for heart failure was 10.6 percent. The remaining lifetime risk of heart failure was approximately 2 percent to 4 percent higher in men with hypertension than in those without hypertension.
The researchers found that normal body weight, never smoking, regular exercise, moderate alcohol intake, and consumption of breakfast cereal and fruits and vegetables were individually associated with a lower lifetime risk of heart failure compared to a corresponding undesirable behavior. There was an inverse and graded association between the number of healthy lifestyle factors and lifetime risk of heart failure. "For example, the lifetime risk for heart failure was approximately 1 in 5 (21.2 percent) in men adhering to none of the desirable lifestyle factors, compared to 1 in 10 (10.1 percent) in those adhering to 4 or more healthy lifestyle factors," the authors write.
When restricted to body weight, smoking, and exercise, the association between lifestyle factors and lifetime risk of heart failure persisted in the overall population as well as in men with and without hypertension.
"Our estimate of lifetime risk of heart failure could help public health officials allocate resources for the prevention and management of this condition. Our findings of a low lifetime risk in men who adhere to modifiable lifestyle factors emphasize the need for incorporation of these behaviors in prevention strategies against heart failure at both the individual and the population level," the authors write.
White Tea vs. Green Tea
When discussing white tea vs green tea, it is important to realize that they both come from the same plant, the tea plant Camellia sinensis. The main difference between the two types of tea is that the white tea leaves are harvested at a younger age than the green tea leaves. They both undergo very little processing. White tea is not fermented at all, while green tea is partly fermented. By contrast, black tea is fully fermented. Because they are so gently treated, white tea and green tea retain their content of beneficial antioxidants.
Antioxidants
However, studies have shown that the young, white tea leaves retain antioxidants in higher concentrations than green tea does. Studies have shown that white tea has a concentration of antioxidants that is three times higher than in green tea. Essentially, white tea contains the same concentrations of antioxidants as the young and fresh tea leaf buds that are still attached to the bush. This makes white tea the tea with the highest antioxidant content, which for many is the main reason for drinking white tea. For comparison, one cup of white tea contains approximately twelve (12) times as much antioxidants as fresh orange juice.
Caffeine
White tea contains less caffeine than green tea, about 15 mg per serving compared to the 20 mg for green tea. If caffeine tends to make you jittery, white tea may be the better choice.
Studies of white tea:
1. "Past studies have shown that green tea stimulates the immune system to fight disease," says Milton Schiffenbauer, Ph.D., a microbiologist and professor in the Department of Biology at Pace University's Dyson College of Arts & Sciences and primary author of the research. "Our research shows White Tea Extract can actually destroy in vitro the organisms that cause disease. Study after study with tea extract proves that it has many healing properties. This is not an old wives tale, it's a fact."
White tea was more effective than green tea at inactivating bacterial viruses. Results obtained with the bacterial virus, a model system; suggest that WTE may have an anti-viral effect on human pathogenic viruses. The addition of White Tea Extract to various toothpastes enhanced the anti-microbial effect of these oral agents.
Studies have also indicated that WTE has an anti-fungal effect on Penicillium chrysogenum and Saccharomyces cerevisiae. In the presence of WTE, Penicillium spores and Saccharomyces cerevisiae yeast cells were totally inactivated. It is suggested that WTE may have an anti-fungal effect on pathogenic fungi.
Several findings in the new study are of particular interest:
* The anti-viral and anti-bacterial effect of white tea (Stash and Templar brands) is greater than that of green tea.
* The anti-viral and anti-bacterial effect of several toothpastes including Aim, Aquafresh, Colgate, Crest and Orajel was enhanced by the addition of white tea extract.
* White tea extract exhibited an anti-fungal effect on both Penicillium chrysogenum and Saccharomyces cerevisiae.
• White tea extract may have application in the inactivation of pathogenic human microbes, i.e., bacteria, viruses, and fungi.
2. Possible anti-obesity effects of white tea have been demonstrated in a series of experiments on human fat cells (adipocytes). Researchers have now shown that an extract of the herbal brew effectively inhibits the generation of new adipocytes and stimulates fat mobilization from mature fat cells.
Marc Winnefeld led a team of researchers from Beiersdorf AG, Germany, who studied the biological effects of an extract of white tea – the least processed version of the tea plant Camellia sinensis. He said, "In the industrialized countries, the rising incidence of obesity-associated disorders including cardiovascular diseases and diabetes constitutes a growing problem. We've shown that white tea may be an ideal natural source of slimming substances".
After treating lab-cultured human pre-adipocytes with the tea extract, the authors found that fat incorporation during the genesis of new adipocytes was reduced. According to Winnefeld, "The extract solution induced a decrease in the expression of genes associated with the growth of new fat cells, while also prompting existing adipocytes to break down the fat they contain".
White tea is made from the buds and first leaves of the plant used to make green tea and the black tea most commonly drunk in Western countries. It is less processed than the other teas and contains more of the ingredients thought to be active on human cells, such as methylxanthines (like caffeine) and epigallocatechin-3-gallate (EGCG) – which the authors believe to be responsible for many of the anti-adipogenic effects demonstrated in their study.
Antioxidants
However, studies have shown that the young, white tea leaves retain antioxidants in higher concentrations than green tea does. Studies have shown that white tea has a concentration of antioxidants that is three times higher than in green tea. Essentially, white tea contains the same concentrations of antioxidants as the young and fresh tea leaf buds that are still attached to the bush. This makes white tea the tea with the highest antioxidant content, which for many is the main reason for drinking white tea. For comparison, one cup of white tea contains approximately twelve (12) times as much antioxidants as fresh orange juice.
Caffeine
White tea contains less caffeine than green tea, about 15 mg per serving compared to the 20 mg for green tea. If caffeine tends to make you jittery, white tea may be the better choice.
Studies of white tea:
1. "Past studies have shown that green tea stimulates the immune system to fight disease," says Milton Schiffenbauer, Ph.D., a microbiologist and professor in the Department of Biology at Pace University's Dyson College of Arts & Sciences and primary author of the research. "Our research shows White Tea Extract can actually destroy in vitro the organisms that cause disease. Study after study with tea extract proves that it has many healing properties. This is not an old wives tale, it's a fact."
White tea was more effective than green tea at inactivating bacterial viruses. Results obtained with the bacterial virus, a model system; suggest that WTE may have an anti-viral effect on human pathogenic viruses. The addition of White Tea Extract to various toothpastes enhanced the anti-microbial effect of these oral agents.
Studies have also indicated that WTE has an anti-fungal effect on Penicillium chrysogenum and Saccharomyces cerevisiae. In the presence of WTE, Penicillium spores and Saccharomyces cerevisiae yeast cells were totally inactivated. It is suggested that WTE may have an anti-fungal effect on pathogenic fungi.
Several findings in the new study are of particular interest:
* The anti-viral and anti-bacterial effect of white tea (Stash and Templar brands) is greater than that of green tea.
* The anti-viral and anti-bacterial effect of several toothpastes including Aim, Aquafresh, Colgate, Crest and Orajel was enhanced by the addition of white tea extract.
* White tea extract exhibited an anti-fungal effect on both Penicillium chrysogenum and Saccharomyces cerevisiae.
• White tea extract may have application in the inactivation of pathogenic human microbes, i.e., bacteria, viruses, and fungi.
2. Possible anti-obesity effects of white tea have been demonstrated in a series of experiments on human fat cells (adipocytes). Researchers have now shown that an extract of the herbal brew effectively inhibits the generation of new adipocytes and stimulates fat mobilization from mature fat cells.
Marc Winnefeld led a team of researchers from Beiersdorf AG, Germany, who studied the biological effects of an extract of white tea – the least processed version of the tea plant Camellia sinensis. He said, "In the industrialized countries, the rising incidence of obesity-associated disorders including cardiovascular diseases and diabetes constitutes a growing problem. We've shown that white tea may be an ideal natural source of slimming substances".
After treating lab-cultured human pre-adipocytes with the tea extract, the authors found that fat incorporation during the genesis of new adipocytes was reduced. According to Winnefeld, "The extract solution induced a decrease in the expression of genes associated with the growth of new fat cells, while also prompting existing adipocytes to break down the fat they contain".
White tea is made from the buds and first leaves of the plant used to make green tea and the black tea most commonly drunk in Western countries. It is less processed than the other teas and contains more of the ingredients thought to be active on human cells, such as methylxanthines (like caffeine) and epigallocatechin-3-gallate (EGCG) – which the authors believe to be responsible for many of the anti-adipogenic effects demonstrated in their study.
Thursday, July 16, 2009
Previous Exercise Helps Stroke Patients Recover Faster
Mayo Clinic Researchers Find Previous Exercise Helps Stroke Patients Recover Faster
A person who has exercised regularly prior to the onset of a stroke appears to recover more quickly, say researchers from Mayo Clinic in Florida, who led a national study.
In the July 2009 issue of the Journal of Neurology, Neurosurgery & Psychiatry, the researchers reported that stroke patients who had previously exercised regularly before a stroke occurred were significantly more likely to have milder impairments and, thus, were better able to care for themselves, compared to patients who rarely exercised.
"It appears that exercise is very beneficial to people at risk of developing a stroke," says Mayo Clinic neurologist James Meschia, M.D., the study's lead investigator. "Many studies have shown that exercise can reduce the risk of developing a stroke in the first place, and this study suggests that if an active person does have a stroke, outcomes can be improved."
Dr. Meschia cautions, however, that a larger study is needed to validate these findings, because this study depended on recall from 673 people who had a stroke. A new study could also help clarify whether moderate or vigorous exercise is necessary to improve outcomes, he says.
"It makes complete sense that a person who exercised before a stroke would recover quicker," Dr. Meschia says. "A brain that generally has good blood and oxygen flow from aerobic exercise will be in a better position to compensate for neurological deficits caused by a stroke."
The findings are potentially important, he adds, because stroke is a common cause of illness, disability, and death among those over age 65 worldwide. In the United States, stroke results in more than 780,000 deaths each year, making it the third leading cause of mortality, and it causes more serious long-term disability than any other disease, according to the National Institutes of Health.
This study is one of the first to examine if the benefits of exercise extend beyond stroke prevention. Researchers looked at data collected by scientists at four centers — Mayo Clinic's campuses in Jacksonville and in Rochester, Minn.; the University of Florida and the University of Virginia — who participated in the Ischemic Stroke Genetics Study. The study was designed to look at inherited risk factors for stroke.
Patients enrolled in the study were treated for acute ischemic stroke — the most common kind of stroke, which results in the death of brain cells due to blockage of blood flow to a part of the brain.
Researchers reviewed a questionnaire patients had completed that asked about exercise before the stroke, and they also looked at measurements of stroke outcome taken after the stroke and then three months later.
Of the 673 patients enrolled, 50.5 percent reported that prior to their stroke, they exercised less than once a week, 28.5 percent exercised one to three times a week, and 21 percent reported aerobic physical activity four times a week or more.
After accounting for different patient variables, such as age, gender, race, body weight and medical history, the researchers found that exercise did not affect the size or severity of a stroke, but did modulate outcomes. Specifically, patients scored better in tests that assessed their ability to perform daily activities involved in living on their own, and determine whether a patient had regained normal functioning.
"We infer that patients who are active may recover more quickly immediately after a stroke, with trends that point to better outcomes at three-month follow-up," says Dr. Meschia.
Researchers could not determine from the data the "dose effect" of the exercise — how much is needed per week for better functioning.
A person who has exercised regularly prior to the onset of a stroke appears to recover more quickly, say researchers from Mayo Clinic in Florida, who led a national study.
In the July 2009 issue of the Journal of Neurology, Neurosurgery & Psychiatry, the researchers reported that stroke patients who had previously exercised regularly before a stroke occurred were significantly more likely to have milder impairments and, thus, were better able to care for themselves, compared to patients who rarely exercised.
"It appears that exercise is very beneficial to people at risk of developing a stroke," says Mayo Clinic neurologist James Meschia, M.D., the study's lead investigator. "Many studies have shown that exercise can reduce the risk of developing a stroke in the first place, and this study suggests that if an active person does have a stroke, outcomes can be improved."
Dr. Meschia cautions, however, that a larger study is needed to validate these findings, because this study depended on recall from 673 people who had a stroke. A new study could also help clarify whether moderate or vigorous exercise is necessary to improve outcomes, he says.
"It makes complete sense that a person who exercised before a stroke would recover quicker," Dr. Meschia says. "A brain that generally has good blood and oxygen flow from aerobic exercise will be in a better position to compensate for neurological deficits caused by a stroke."
The findings are potentially important, he adds, because stroke is a common cause of illness, disability, and death among those over age 65 worldwide. In the United States, stroke results in more than 780,000 deaths each year, making it the third leading cause of mortality, and it causes more serious long-term disability than any other disease, according to the National Institutes of Health.
This study is one of the first to examine if the benefits of exercise extend beyond stroke prevention. Researchers looked at data collected by scientists at four centers — Mayo Clinic's campuses in Jacksonville and in Rochester, Minn.; the University of Florida and the University of Virginia — who participated in the Ischemic Stroke Genetics Study. The study was designed to look at inherited risk factors for stroke.
Patients enrolled in the study were treated for acute ischemic stroke — the most common kind of stroke, which results in the death of brain cells due to blockage of blood flow to a part of the brain.
Researchers reviewed a questionnaire patients had completed that asked about exercise before the stroke, and they also looked at measurements of stroke outcome taken after the stroke and then three months later.
Of the 673 patients enrolled, 50.5 percent reported that prior to their stroke, they exercised less than once a week, 28.5 percent exercised one to three times a week, and 21 percent reported aerobic physical activity four times a week or more.
After accounting for different patient variables, such as age, gender, race, body weight and medical history, the researchers found that exercise did not affect the size or severity of a stroke, but did modulate outcomes. Specifically, patients scored better in tests that assessed their ability to perform daily activities involved in living on their own, and determine whether a patient had regained normal functioning.
"We infer that patients who are active may recover more quickly immediately after a stroke, with trends that point to better outcomes at three-month follow-up," says Dr. Meschia.
Researchers could not determine from the data the "dose effect" of the exercise — how much is needed per week for better functioning.
Wednesday, July 15, 2009
Vitamin D, curcumin may help fight Alzheimer's
Early research findings may lead to new treatments for the disease
UCLA scientists and colleagues from UC Riverside and the Human BioMolecular Research Institute have found that a form of vitamin D, together with a chemical found in turmeric spice called curcumin, may help stimulate the immune system to clear the brain of amyloid beta, which forms the plaques considered the hallmark of Alzheimer's disease.
The early research findings, which appear in the July issue of the Journal of Alzheimer's Disease, may lead to new approaches in preventing and treating Alzheimer's by utilizing the property of vitamin D3 — a form of vitamin D — both alone and together with natural or synthetic curcumin to boost the immune system in protecting the brain against amyloid beta.
Vitamin D3 is an essential nutrient for bone and immune system health; its main source is sunshine, and it is synthesized through the skin. Deficiencies may occur during winter months or in those who spend a lot of time indoors, such as Alzheimer's patients.
"We hope that vitamin D3 and curcumin, both naturally occurring nutrients, may offer new preventive and treatment possibilities for Alzheimer's disease," said Dr. Milan Fiala, study author and a researcher at the David Geffen School of Medicine at UCLA and the Veterans Affairs Greater Los Angeles Healthcare System.
Using blood samples from nine Alzheimer's patients, one patient with mild cognitive impairment and three healthy control subjects, scientists isolated monocyte cells, which transform into macrophages that act as the immune system's clean-up crew, traveling through the brain and body and gobbling up waste products, including amyloid beta. Researchers incubated the macrophages with amyloid beta, vitamin D3 and natural or synthetic curcumin.
The synthetic curcuminoid compounds were developed in the laboratory of John Cashman at the Human BioMolecular Research Institute, (http://www.hbri.org/), a nonprofit institute dedicated to research on diseases of the human brain.Researchers found that naturally occurring curcumin was not readily absorbed, that it tended to break down quickly before it could be utilized and that its potency level was low, making it less effective than the new synthetic curcuminoids.
"We think some of the novel synthetic compounds will get around the shortcomings of curcumin and improve the therapeutic efficacy," Cashman said.
The team discovered that curcuminoids enhanced the surface binding of amyloid beta to macrophages and that vitamin D strongly stimulated the uptake and absorption of amyloid beta in macrophages in a majority of patients.
Previous research by the team demonstrated that the immune genes MGAT III and TLR-3 are associated with the immune system's ability to better ingest amyloid beta. In this earlier work, Fiala noted, it was shown that there are two types of Alzheimer's patients: Type 1 patients, who respond positively to curcuminoids, and Type II patients, who do not.
"Since vitamin D and curcumin work differently with the immune system, we may find that a combination of the two or each used alone may be more effective — depending on the individual patient," he said.
Fiala noted that this is early laboratory research and that no dosage of vitamin D or curcumin can be recommended at this point. Larger vitamin D and curcumin studies with more patients are planned.
UCLA scientists and colleagues from UC Riverside and the Human BioMolecular Research Institute have found that a form of vitamin D, together with a chemical found in turmeric spice called curcumin, may help stimulate the immune system to clear the brain of amyloid beta, which forms the plaques considered the hallmark of Alzheimer's disease.
The early research findings, which appear in the July issue of the Journal of Alzheimer's Disease, may lead to new approaches in preventing and treating Alzheimer's by utilizing the property of vitamin D3 — a form of vitamin D — both alone and together with natural or synthetic curcumin to boost the immune system in protecting the brain against amyloid beta.
Vitamin D3 is an essential nutrient for bone and immune system health; its main source is sunshine, and it is synthesized through the skin. Deficiencies may occur during winter months or in those who spend a lot of time indoors, such as Alzheimer's patients.
"We hope that vitamin D3 and curcumin, both naturally occurring nutrients, may offer new preventive and treatment possibilities for Alzheimer's disease," said Dr. Milan Fiala, study author and a researcher at the David Geffen School of Medicine at UCLA and the Veterans Affairs Greater Los Angeles Healthcare System.
Using blood samples from nine Alzheimer's patients, one patient with mild cognitive impairment and three healthy control subjects, scientists isolated monocyte cells, which transform into macrophages that act as the immune system's clean-up crew, traveling through the brain and body and gobbling up waste products, including amyloid beta. Researchers incubated the macrophages with amyloid beta, vitamin D3 and natural or synthetic curcumin.
The synthetic curcuminoid compounds were developed in the laboratory of John Cashman at the Human BioMolecular Research Institute, (http://www.hbri.org/), a nonprofit institute dedicated to research on diseases of the human brain.Researchers found that naturally occurring curcumin was not readily absorbed, that it tended to break down quickly before it could be utilized and that its potency level was low, making it less effective than the new synthetic curcuminoids.
"We think some of the novel synthetic compounds will get around the shortcomings of curcumin and improve the therapeutic efficacy," Cashman said.
The team discovered that curcuminoids enhanced the surface binding of amyloid beta to macrophages and that vitamin D strongly stimulated the uptake and absorption of amyloid beta in macrophages in a majority of patients.
Previous research by the team demonstrated that the immune genes MGAT III and TLR-3 are associated with the immune system's ability to better ingest amyloid beta. In this earlier work, Fiala noted, it was shown that there are two types of Alzheimer's patients: Type 1 patients, who respond positively to curcuminoids, and Type II patients, who do not.
"Since vitamin D and curcumin work differently with the immune system, we may find that a combination of the two or each used alone may be more effective — depending on the individual patient," he said.
Fiala noted that this is early laboratory research and that no dosage of vitamin D or curcumin can be recommended at this point. Larger vitamin D and curcumin studies with more patients are planned.
Tuesday, July 14, 2009
Best Way To Get Vitamin D
The American Academy of Dermatology (Academy) recently issued an updated position statement on vitamin D after an updated review of the increasing body of scientific literature on this vitamin and its importance for optimal health.
The Academy continues to recommend that the public obtain vitamin D from nutritional sources and dietary supplements, and not from unprotected exposure to ultraviolet (UV) radiation from the sun or indoor tanning devices, as UV radiation is a known risk factor for the development of skin cancer.
The Academy’s position statement on vitamin D now also states that individuals who regularly and properly practice sun protection, such as the daily use of sunscreen on exposed skin or the wearing of sun protective clothing, may be at risk for vitamin D insufficiency. A higher dose of vitamin D may be necessary for these individuals and others with known risk factors for vitamin D insufficiency, such as those with dark skin, the elderly, photosensitive individuals, people with limited sun exposure, obese individuals or those with fat malabsorption. Therefore, the Academy encourages those with concerns about their levels of vitamin D to discuss options for obtaining sufficient dietary or supplementary sources of vitamin D with their physician.
“The vitamin D position statement supports the Academy’s long-held conviction on safe ways to get this important vitamin – through a healthy diet which incorporates foods naturally rich in vitamin D, vitamin D-fortified foods and beverages, and vitamin D supplements,” stated dermatologist David M. Pariser, MD, FAAD, president of the American Academy of Dermatology. “The updated recommendation for individuals who practice daily sun protection acknowledges that while protecting the skin from the damaging rays of the sun is important, so is maintaining adequate vitamin D levels. Concern about vitamin D should not lead people to forego sun protection, but rather prompt a conversation with their physician about how to ensure adequate and safe vitamin D intake while guarding against skin cancer .”
The Academy’s new position statement notes that the National Academy of Sciences Institute of Medicine guidelines for vitamin D are the standard reference for advising patients on proper minimum intake levels. The currently recommended adequate intake levels established by the Institute of Medicine may be revised upward due to evolving research on the increasing clinical benefit of vitamin D. The statement also notes that the U.S. Department of Agriculture (USDA) Dietary Guidelines discuss a daily total dose of 1,000 IU (International Units) of vitamin D for supplementation of those at-risk for vitamin D insufficiency.
The Academy’s new position statement also asserts that there is no scientifically proven, safe threshold of sun or indoor tanning device exposure that allows for maximum vitamin D synthesis in the skin without increasing the risk of skin cancer. Also, while numerous studies suggest an association between low levels of vitamin D and an increased risk of certain types of cancers and diseases, the Academy emphasizes that the causal relationship of vitamin D to these disease outcomes has yet to be demonstrated with clinical trials.
“It is well documented in the medical literature that unprotected exposure to UV radiation from natural sunlight or indoor tanning devices causes skin damage. There is no current research available that provides a safe limit for sun exposure to maximize vitamin D production that does not put the individuals health at risk for developing skin cancer,” stated Dr. Pariser. “In addition, contrary to some reported information about vitamin D and the prevention of certain cancers and diseases--other than for bone health, we simply need more clinical data to determine what role, if any, vitamin D plays in these conditions.”
The Academy continues to recommend that individuals protect themselves from UV exposure when outdoors, such as seeking shade whenever possible, wearing sunscreen and covering up with a wide-brimmed hat, long sleeves, pants and sunglasses. Also, the Academy urges the public to avoid tanning beds.
For more information about skin cancer, please visit the SkinCancerNet section on www.skincarephysicians.com, a Web site developed by dermatologists that provides the public with up-to-date information.
To help the general public better understand the relationship between vitamin D and the sun, the National Council on Skin Cancer Prevention has issued a position statement on vitamin D, sun protection and skin cancer prevention. The Council recommends that vitamin D be obtained from a combination of dietary sources and supplements and not through intentional exposure to ultraviolet (UV) radiation.
“For those who are concerned about vitamin D insufficiency, diet and vitamin D supplementation are the most appropriate methods to obtain adequate vitamin D – it is not appropriate to seek exposure to ultraviolet radiation,” says dermatologist Henry Lim, MD, FAAD, Council co-chair and chairman of dermatology at Henry Ford Hospital, Detroit, MI.
UV radiation, a known carcinogen, can cause a range of health problems, including skin cancer, cataracts, premature aging, and immune suppression. With more than one million skin cancers diagnosed annually, skin cancer is the most common form of cancer in the United States. Each year, there are more new cases of skin cancer than the combined number of new cases of breast, prostate, lung and colon cancer.
While UVB radiation is one source of vitamin D, the benefits of exposure to UVB radiation cannot be separated from its harmful effects. For this reason, the safest way to obtain adequate vitamin D is through a combination of diet and vitamin D supplements.
According to the latest version of the U.S. Departments of Agriculture and Health and Human Services’ Dietary Guidelines for Americans 2005, adults with limited sun exposure (e.g., the housebound population) should ingest extra vitamin D from vitamin D-fortified foods and/or supplements. For this group of individuals, an intake of 1000 international units (IUs) of vitamin D per day for adults is recommended. For children under 18 years of age, including infants, the American Academy of Pediatrics recommends 400 IU of vitamin D per day.
Because sufficient vitamin D can be acquired through diet and vitamin supplements, the Council recommends that adults and children practice comprehensive sun-protection behaviors and avoid intentional exposure to natural sunlight and artificial UV radiation (tanning beds) as a means to obtain vitamin D.
Practicing a comprehensive sun-protection regimen to avoid the risk of skin cancer is essential. The National Council’s prevention guidelines include: seeking the shade between 10 am and 4 pm, generously applying sunscreen with a sun protection factor (SPF) of 15 or higher, and wearing sun-protective clothing, including wide brimmed hats and UV-protective sunglasses. For the full guidelines and the position statement, visit www.skincancerprevention.org . For a list of vitamin D sources in a typical diet, visit the National Institutes of Health Office of Dietary Supplements website: http://ods.od.nih.gov/factsheets/vitamind.asp.
The Academy continues to recommend that the public obtain vitamin D from nutritional sources and dietary supplements, and not from unprotected exposure to ultraviolet (UV) radiation from the sun or indoor tanning devices, as UV radiation is a known risk factor for the development of skin cancer.
The Academy’s position statement on vitamin D now also states that individuals who regularly and properly practice sun protection, such as the daily use of sunscreen on exposed skin or the wearing of sun protective clothing, may be at risk for vitamin D insufficiency. A higher dose of vitamin D may be necessary for these individuals and others with known risk factors for vitamin D insufficiency, such as those with dark skin, the elderly, photosensitive individuals, people with limited sun exposure, obese individuals or those with fat malabsorption. Therefore, the Academy encourages those with concerns about their levels of vitamin D to discuss options for obtaining sufficient dietary or supplementary sources of vitamin D with their physician.
“The vitamin D position statement supports the Academy’s long-held conviction on safe ways to get this important vitamin – through a healthy diet which incorporates foods naturally rich in vitamin D, vitamin D-fortified foods and beverages, and vitamin D supplements,” stated dermatologist David M. Pariser, MD, FAAD, president of the American Academy of Dermatology. “The updated recommendation for individuals who practice daily sun protection acknowledges that while protecting the skin from the damaging rays of the sun is important, so is maintaining adequate vitamin D levels. Concern about vitamin D should not lead people to forego sun protection, but rather prompt a conversation with their physician about how to ensure adequate and safe vitamin D intake while guarding against skin cancer .”
The Academy’s new position statement notes that the National Academy of Sciences Institute of Medicine guidelines for vitamin D are the standard reference for advising patients on proper minimum intake levels. The currently recommended adequate intake levels established by the Institute of Medicine may be revised upward due to evolving research on the increasing clinical benefit of vitamin D. The statement also notes that the U.S. Department of Agriculture (USDA) Dietary Guidelines discuss a daily total dose of 1,000 IU (International Units) of vitamin D for supplementation of those at-risk for vitamin D insufficiency.
The Academy’s new position statement also asserts that there is no scientifically proven, safe threshold of sun or indoor tanning device exposure that allows for maximum vitamin D synthesis in the skin without increasing the risk of skin cancer. Also, while numerous studies suggest an association between low levels of vitamin D and an increased risk of certain types of cancers and diseases, the Academy emphasizes that the causal relationship of vitamin D to these disease outcomes has yet to be demonstrated with clinical trials.
“It is well documented in the medical literature that unprotected exposure to UV radiation from natural sunlight or indoor tanning devices causes skin damage. There is no current research available that provides a safe limit for sun exposure to maximize vitamin D production that does not put the individuals health at risk for developing skin cancer,” stated Dr. Pariser. “In addition, contrary to some reported information about vitamin D and the prevention of certain cancers and diseases--other than for bone health, we simply need more clinical data to determine what role, if any, vitamin D plays in these conditions.”
The Academy continues to recommend that individuals protect themselves from UV exposure when outdoors, such as seeking shade whenever possible, wearing sunscreen and covering up with a wide-brimmed hat, long sleeves, pants and sunglasses. Also, the Academy urges the public to avoid tanning beds.
For more information about skin cancer, please visit the SkinCancerNet section on www.skincarephysicians.com, a Web site developed by dermatologists that provides the public with up-to-date information.
To help the general public better understand the relationship between vitamin D and the sun, the National Council on Skin Cancer Prevention has issued a position statement on vitamin D, sun protection and skin cancer prevention. The Council recommends that vitamin D be obtained from a combination of dietary sources and supplements and not through intentional exposure to ultraviolet (UV) radiation.
“For those who are concerned about vitamin D insufficiency, diet and vitamin D supplementation are the most appropriate methods to obtain adequate vitamin D – it is not appropriate to seek exposure to ultraviolet radiation,” says dermatologist Henry Lim, MD, FAAD, Council co-chair and chairman of dermatology at Henry Ford Hospital, Detroit, MI.
UV radiation, a known carcinogen, can cause a range of health problems, including skin cancer, cataracts, premature aging, and immune suppression. With more than one million skin cancers diagnosed annually, skin cancer is the most common form of cancer in the United States. Each year, there are more new cases of skin cancer than the combined number of new cases of breast, prostate, lung and colon cancer.
While UVB radiation is one source of vitamin D, the benefits of exposure to UVB radiation cannot be separated from its harmful effects. For this reason, the safest way to obtain adequate vitamin D is through a combination of diet and vitamin D supplements.
According to the latest version of the U.S. Departments of Agriculture and Health and Human Services’ Dietary Guidelines for Americans 2005, adults with limited sun exposure (e.g., the housebound population) should ingest extra vitamin D from vitamin D-fortified foods and/or supplements. For this group of individuals, an intake of 1000 international units (IUs) of vitamin D per day for adults is recommended. For children under 18 years of age, including infants, the American Academy of Pediatrics recommends 400 IU of vitamin D per day.
Because sufficient vitamin D can be acquired through diet and vitamin supplements, the Council recommends that adults and children practice comprehensive sun-protection behaviors and avoid intentional exposure to natural sunlight and artificial UV radiation (tanning beds) as a means to obtain vitamin D.
Practicing a comprehensive sun-protection regimen to avoid the risk of skin cancer is essential. The National Council’s prevention guidelines include: seeking the shade between 10 am and 4 pm, generously applying sunscreen with a sun protection factor (SPF) of 15 or higher, and wearing sun-protective clothing, including wide brimmed hats and UV-protective sunglasses. For the full guidelines and the position statement, visit www.skincancerprevention.org . For a list of vitamin D sources in a typical diet, visit the National Institutes of Health Office of Dietary Supplements website: http://ods.od.nih.gov/factsheets/vitamind.asp.
Green tea fights several kinds of cancer
A large new review of studies that examined the affect of green tea on cancer prevention has yielded promising results.
Researchers looked at 51 medium- to high-quality studies that included more than 1.6 million participants. The studies focused on the relationship between green tea consumption and a variety of cancers, including breast, lung, digestive tract, urological prostate, gynecological and oral cancers.
The comprehensive review analyzed studies conducted from 1985 through 2008. Many of the reviewed studies took place in Asia, where tea drinking is widespread and part of the daily routine for many.
Three types of tea — black, green and oolong — come from the plant Camellia sinensis, and all contain polyphenols. Catechins, a subgroup of the polyphenols, are powerful antioxidants. Some say the polyphenols in green tea are unique, preventing cell growth and thus having the potential to prevent cancer.
The review found that green tea had limited benefits for liver cancer, but found conflicting evidence for other gastrointestinal cancers, such as cancer of the esophagus, colon or pancreas. One study found a decreased risk of prostate cancer for men who consumed higher quantities of green tea or its extracts.
The review did not find any benefit for preventing death from gastric cancer, and found that green tea might even increase the risk of urinary bladder cancer. Despite conflicting findings, there was “limited moderate to strong evidence” of a benefit for lung, pancreatic and colorectal cancer. None of the studies that simply observed a group of people over time found a benefit for breast cancer prevention. However, both of the case control studies — which compare people without a condition to people with it — found a positive association between green tea consumption and a decreased risk of breast cancer.
Nagi Kumar, Ph.D., director of Nutrition Research at Moffitt Cancer Center in Tampa, Fla., is optimistic about the potential for green tea in cancer prevention. “The substances found in green tea are certainly promising,” Kumar said. “The field now has progressed to where we [can]…test the effectiveness and safety of green tea polyphenols using a drug form similar to the constituents in tea to see if we can prevent cancer progression. Time will tell.”
Kumar said the Cochrane review was “more an inventory of studies completed rather than a systematic scientific review,” adding that “the discussion lacks a scientific approach in the interpretation of the discordant findings.”
Kumar also noted that several groups are conducting randomized clinical trials, including one comprising six institutions: the Moffitt Cancer Center and the James A Haley VA Medical Center, University of Chicago, Jefferson in Philadelphia, University of Florida and Louisiana State University.
Both scientists agreed that more research is a good idea. Boehm said she highly recommends the conduction of a large, well-designed, study with adequate green tea consumption levels.
“The review provides where we have been in this field of research and where we are going and how much more we have on hand,” Kumar said. “Although not as thorough as I would like it, it is a good quality review.”
Therefore, while the questions about green tea consumption and cancer prevention remain unanswered, one thing remains clear: It is fine to consume green tea if you enjoy it and it might prove beneficial in the over time.
“If not exceeding the daily recommended allowance those who enjoy a cup of green tea should continue its consumption,” Boehm said. “Drinking green tea appears to be safe at regular, habitual and moderate use at its recommended dosage of up to 1200 ml/day.” That comes to a little over five cups a day.
Researchers looked at 51 medium- to high-quality studies that included more than 1.6 million participants. The studies focused on the relationship between green tea consumption and a variety of cancers, including breast, lung, digestive tract, urological prostate, gynecological and oral cancers.
The comprehensive review analyzed studies conducted from 1985 through 2008. Many of the reviewed studies took place in Asia, where tea drinking is widespread and part of the daily routine for many.
Three types of tea — black, green and oolong — come from the plant Camellia sinensis, and all contain polyphenols. Catechins, a subgroup of the polyphenols, are powerful antioxidants. Some say the polyphenols in green tea are unique, preventing cell growth and thus having the potential to prevent cancer.
The review found that green tea had limited benefits for liver cancer, but found conflicting evidence for other gastrointestinal cancers, such as cancer of the esophagus, colon or pancreas. One study found a decreased risk of prostate cancer for men who consumed higher quantities of green tea or its extracts.
The review did not find any benefit for preventing death from gastric cancer, and found that green tea might even increase the risk of urinary bladder cancer. Despite conflicting findings, there was “limited moderate to strong evidence” of a benefit for lung, pancreatic and colorectal cancer. None of the studies that simply observed a group of people over time found a benefit for breast cancer prevention. However, both of the case control studies — which compare people without a condition to people with it — found a positive association between green tea consumption and a decreased risk of breast cancer.
Nagi Kumar, Ph.D., director of Nutrition Research at Moffitt Cancer Center in Tampa, Fla., is optimistic about the potential for green tea in cancer prevention. “The substances found in green tea are certainly promising,” Kumar said. “The field now has progressed to where we [can]…test the effectiveness and safety of green tea polyphenols using a drug form similar to the constituents in tea to see if we can prevent cancer progression. Time will tell.”
Kumar said the Cochrane review was “more an inventory of studies completed rather than a systematic scientific review,” adding that “the discussion lacks a scientific approach in the interpretation of the discordant findings.”
Kumar also noted that several groups are conducting randomized clinical trials, including one comprising six institutions: the Moffitt Cancer Center and the James A Haley VA Medical Center, University of Chicago, Jefferson in Philadelphia, University of Florida and Louisiana State University.
Both scientists agreed that more research is a good idea. Boehm said she highly recommends the conduction of a large, well-designed, study with adequate green tea consumption levels.
“The review provides where we have been in this field of research and where we are going and how much more we have on hand,” Kumar said. “Although not as thorough as I would like it, it is a good quality review.”
Therefore, while the questions about green tea consumption and cancer prevention remain unanswered, one thing remains clear: It is fine to consume green tea if you enjoy it and it might prove beneficial in the over time.
“If not exceeding the daily recommended allowance those who enjoy a cup of green tea should continue its consumption,” Boehm said. “Drinking green tea appears to be safe at regular, habitual and moderate use at its recommended dosage of up to 1200 ml/day.” That comes to a little over five cups a day.
Diet, Exercise Improve Late Cognitive Skills
Dietary Approaches to Stop Hypertension (DASH) Eating Pattern May Reduce Age-Related Cognitive Decline
The Dietary Approaches to Stop Hypertension (DASH) diet is often recommended by physicians to people with high blood pressure or pre-hypertension. The DASH diet eating plan has been proven to lower blood pressure in studies sponsored by the National Institutes of Health. High blood pressure is considered a risk factor for Alzheimer's and dementia.
Heidi Wengreen, RD, PhD, Assistant Professor of Nutrition at Utah State University, and colleagues examined associations between how closely people adhered to the DASH diet and risk of cognitive decline and dementia among older participants in the Cache County Study on Memory, Health and Aging.
In 1995, 3,831 study participants 65 years of age or older completed a survey that included a food frequency questionnaire and cognitive assessment. Cognitive function was checked again during four assessments over 11 years using the Modified Mini-Mental State examination (3MS), which is graded on a 100 point scale. A DASH diet adherence score was created based on consumption levels of nine food-group/nutrient components -- fruit, vegetables, nut/legumes, whole grains, low-fat dairy, sodium, sweets, non-fish meat, and fish. Participants were ranked by DASH score into five groups, or quintiles.
The researchers found that higher DASH scores were associated with higher scores for cognitive functioning at the beginning of the study and over time. Those in the highest quintile scored 1.42 points higher at baseline and 1.81 points higher after 11 years on the 3MS than did those in the lowest quintile of the DASH score (p-values < 0.001).
They also found that four of the nine food-group/nutrient components used to create the DASH score were independently associated with 3MS scores -- vegetables, whole grains, low-fat dairy, nut/legumes. The scientists created a diet adherence score based on just these four components which they then tested for association with changes in cognitive abilities on the 3MS. Those in the highest quintile scored 1.72 points higher at baseline and 3.73 points higher after 11 years than did those in the lowest quintile of the four-component score (p-values < 0.001).
"Our results suggest that including whole grains, vegetables, low-fat dairy foods, and nuts in one's diet may offer benefits for cognition in late life," Wengreen said. "However, we need more research before we can confidently say how much of these foods to include in your diet to experience some benefit."
Maintaining or Increasing Activity Levels May Slow Cognitive Decline in Elderly
Studies have found that older adults who are physically active may experience slower rates of cognitive decline. Less is known about the impact of changes in physical activity levels on rate of cognitive decline.
Deborah E. Barnes, PhD, MPH, Assistant Professor of Psychiatry at the University of California, San Francisco, and a geriatrics researcher at the San Francisco VA Medical Center, and colleagues studied changes in levels of both physical activity and cognitive function over seven years in 3,075 white and black elders aged 70-79 years in the Health, Aging and Body Composition Study. Physical activity was assessed based on self-reported number of minutes walked per week at the beginning of the study and after two, four, and seven years of follow-up. Participants were classified at each time point as sedentary (0 minutes per week), low (less than 150 minutes per week) or high (150 minutes per week or more). Changes over time were classified as consistently sedentary, maintaining (low or high), decreasing, or increasing/fluctuating. Cognitive function was assessed using the 3MS.
The researchers found that 21% of study participants were consistently sedentary, 12% maintained their activity levels, 26% had declining levels, and 41% had increasing or fluctuating levels. After adjustment for age, sex, race, education, study site, diabetes, hypertension, smoking, alcohol consumption and baseline 3MS score, they found that the mean rate of decline in 3MS scores was 0.62 points/year in those who were consistently sedentary, 0.54 points/year (p=0.30) in those with declining activity levels, 0.44 points/year (p=0.01) in those with increasing/fluctuating activity levels, and 0.40 points/year (p=0.04) in those who maintained their activity levels.
"We found that older adults who were sedentary throughout the study had the lowest levels of cognitive function at the beginning and experienced the fastest rate of cognitive decline," Barnes said. "Cognitive decline also was faster in those whose physical activity levels consistently declined during the study period."
According to the researchers, sedentary elders who began new aerobic exercise programs experienced improvements in cognitive function, especially the ability to process complex information quickly. "Sedentary individuals should be encouraged to engage in physical activity at least occasionally," Barnes said. "People who are currently active should be encouraged to maintain or increase their activity levels."
Moderate Long-Term Physical Activity May Improve Late Life Cognition; Long-Term Strenuous Activity May Increase Risk of Cognitive Impairment
Long-term strenuous physical activity has been shown to decrease lifetime exposure to ovarian hormones in women and has been found to play a protective role against breast cancer. However reduction in ovarian hormone exposure has been associated with increased risk of cognitive impairment. At the same time, long-term physical activity is associated with improved cognition but the intensity required to preserve cognition is not known.
Mary C. Tierney, PhD, CPsych, Professor of Family and Community Medicine at the University of Toronto, and Senior Scientist and Director, Geriatric Research Unit, Brain Sciences Program at Sunnybrook Health Sciences Centre, and colleagues sought to examine the associations between both long-term strenuous and moderate activity levels and cognition in recently postmenopausal women.
Study participants were 90 women aged 50-63 years, one to 10 years post natural menopause, with no history of breast cancer, HRT use, psychiatric disorder, dementia or other neurological condition. Participants gave details on the amount of their strenuous and moderate physical recreational activities from high school to menopause. Eight memory and brain function tests were administered to all participants.
After adjusting for age, education, reproductive years, cigarette smoking, alcohol consumption, parity, and periods of amenorrhea, the researchers found that long-term strenuous activity was consistently associated with poorer performance on all eight of the tests; with statistically significant results on tests of semantic memory, working memory, delayed verbal recall, and sustained attention (p < 0.05). Moderate physical activity was consistently associated with better performance on all eight of the tests, with statistically significant results on cognitive flexibility, working memory, and sustained attention (p < 0.05).
"Our results suggest that long-term strenuous activity may increase the risk of cognitive impairment in recently postmenopausal women," Tierney said. "On the other hand, moderate long-term physical activity may improve later life cognition. These preliminary findings have important implications for women's health and support the need for large-scale studies including both women and men."
The Dietary Approaches to Stop Hypertension (DASH) diet is often recommended by physicians to people with high blood pressure or pre-hypertension. The DASH diet eating plan has been proven to lower blood pressure in studies sponsored by the National Institutes of Health. High blood pressure is considered a risk factor for Alzheimer's and dementia.
Heidi Wengreen, RD, PhD, Assistant Professor of Nutrition at Utah State University, and colleagues examined associations between how closely people adhered to the DASH diet and risk of cognitive decline and dementia among older participants in the Cache County Study on Memory, Health and Aging.
In 1995, 3,831 study participants 65 years of age or older completed a survey that included a food frequency questionnaire and cognitive assessment. Cognitive function was checked again during four assessments over 11 years using the Modified Mini-Mental State examination (3MS), which is graded on a 100 point scale. A DASH diet adherence score was created based on consumption levels of nine food-group/nutrient components -- fruit, vegetables, nut/legumes, whole grains, low-fat dairy, sodium, sweets, non-fish meat, and fish. Participants were ranked by DASH score into five groups, or quintiles.
The researchers found that higher DASH scores were associated with higher scores for cognitive functioning at the beginning of the study and over time. Those in the highest quintile scored 1.42 points higher at baseline and 1.81 points higher after 11 years on the 3MS than did those in the lowest quintile of the DASH score (p-values < 0.001).
They also found that four of the nine food-group/nutrient components used to create the DASH score were independently associated with 3MS scores -- vegetables, whole grains, low-fat dairy, nut/legumes. The scientists created a diet adherence score based on just these four components which they then tested for association with changes in cognitive abilities on the 3MS. Those in the highest quintile scored 1.72 points higher at baseline and 3.73 points higher after 11 years than did those in the lowest quintile of the four-component score (p-values < 0.001).
"Our results suggest that including whole grains, vegetables, low-fat dairy foods, and nuts in one's diet may offer benefits for cognition in late life," Wengreen said. "However, we need more research before we can confidently say how much of these foods to include in your diet to experience some benefit."
Maintaining or Increasing Activity Levels May Slow Cognitive Decline in Elderly
Studies have found that older adults who are physically active may experience slower rates of cognitive decline. Less is known about the impact of changes in physical activity levels on rate of cognitive decline.
Deborah E. Barnes, PhD, MPH, Assistant Professor of Psychiatry at the University of California, San Francisco, and a geriatrics researcher at the San Francisco VA Medical Center, and colleagues studied changes in levels of both physical activity and cognitive function over seven years in 3,075 white and black elders aged 70-79 years in the Health, Aging and Body Composition Study. Physical activity was assessed based on self-reported number of minutes walked per week at the beginning of the study and after two, four, and seven years of follow-up. Participants were classified at each time point as sedentary (0 minutes per week), low (less than 150 minutes per week) or high (150 minutes per week or more). Changes over time were classified as consistently sedentary, maintaining (low or high), decreasing, or increasing/fluctuating. Cognitive function was assessed using the 3MS.
The researchers found that 21% of study participants were consistently sedentary, 12% maintained their activity levels, 26% had declining levels, and 41% had increasing or fluctuating levels. After adjustment for age, sex, race, education, study site, diabetes, hypertension, smoking, alcohol consumption and baseline 3MS score, they found that the mean rate of decline in 3MS scores was 0.62 points/year in those who were consistently sedentary, 0.54 points/year (p=0.30) in those with declining activity levels, 0.44 points/year (p=0.01) in those with increasing/fluctuating activity levels, and 0.40 points/year (p=0.04) in those who maintained their activity levels.
"We found that older adults who were sedentary throughout the study had the lowest levels of cognitive function at the beginning and experienced the fastest rate of cognitive decline," Barnes said. "Cognitive decline also was faster in those whose physical activity levels consistently declined during the study period."
According to the researchers, sedentary elders who began new aerobic exercise programs experienced improvements in cognitive function, especially the ability to process complex information quickly. "Sedentary individuals should be encouraged to engage in physical activity at least occasionally," Barnes said. "People who are currently active should be encouraged to maintain or increase their activity levels."
Moderate Long-Term Physical Activity May Improve Late Life Cognition; Long-Term Strenuous Activity May Increase Risk of Cognitive Impairment
Long-term strenuous physical activity has been shown to decrease lifetime exposure to ovarian hormones in women and has been found to play a protective role against breast cancer. However reduction in ovarian hormone exposure has been associated with increased risk of cognitive impairment. At the same time, long-term physical activity is associated with improved cognition but the intensity required to preserve cognition is not known.
Mary C. Tierney, PhD, CPsych, Professor of Family and Community Medicine at the University of Toronto, and Senior Scientist and Director, Geriatric Research Unit, Brain Sciences Program at Sunnybrook Health Sciences Centre, and colleagues sought to examine the associations between both long-term strenuous and moderate activity levels and cognition in recently postmenopausal women.
Study participants were 90 women aged 50-63 years, one to 10 years post natural menopause, with no history of breast cancer, HRT use, psychiatric disorder, dementia or other neurological condition. Participants gave details on the amount of their strenuous and moderate physical recreational activities from high school to menopause. Eight memory and brain function tests were administered to all participants.
After adjusting for age, education, reproductive years, cigarette smoking, alcohol consumption, parity, and periods of amenorrhea, the researchers found that long-term strenuous activity was consistently associated with poorer performance on all eight of the tests; with statistically significant results on tests of semantic memory, working memory, delayed verbal recall, and sustained attention (p < 0.05). Moderate physical activity was consistently associated with better performance on all eight of the tests, with statistically significant results on cognitive flexibility, working memory, and sustained attention (p < 0.05).
"Our results suggest that long-term strenuous activity may increase the risk of cognitive impairment in recently postmenopausal women," Tierney said. "On the other hand, moderate long-term physical activity may improve later life cognition. These preliminary findings have important implications for women's health and support the need for large-scale studies including both women and men."
Monday, July 13, 2009
Naringenin, a citrus-derived flavonoid, prevents obesity
A flavonoid derived from citrus fruit has shown tremendous promise for preventing weight gain and other signs of metabolic syndrome which can lead to Type 2 Diabetes and increased risk of cardiovascular disease. The study, led by Murray Huff of the Robarts Research Institute at The University of Western Ontario looked at a flavonoid (plant-based bioactive molecule) called naringenin. The findings are published online in the journal Diabetes.
In the study one group of mice was fed a high-fat (western) diet to induce the symptoms of metabolic syndrome. A second group was fed the exact same diet and treated with naringenin. Naringenin corrected the elevations in triglyceride and cholesterol, prevented the development of insulin resistance and completely normalized glucose metabolism. The researchers found it worked by genetically reprogramming the liver to burn up excess fat, rather than store it.
"Furthermore, the marked obesity that develops in these mice was completely prevented by naringenin," says Huff, Director of the Vascular Biology Research Group at Robarts and Professor of Medicine and Biochemistry at the Schulich School of Medicine & Dentistry. "What was unique about the study was that the effects were independent of caloric intake, meaning the mice ate exactly the same amount of food and the same amount of fat. There was no suppression of appetite or decreased food intake, which are often the basis of strategies to reduce weight gain and its metabolic consequences."
While grapefruit has long been linked to weight loss diets, the concentrations of the citrus-derived flavonoid being studied are at higher levels than you could get from dietary components. "We are examining the pharmacological properties of naringenin," explains Huff. "The next step is to find out if naringenin prevents heart disease in animal models and to explore the feasibility of clinical trials to determine its safety and efficacy in humans."
This study investigated naringenin's preventative properties, but Huff is also investigating whether it can treat obesity and other existing metabolic problems. "These studies show naringenin, through its insulin-like properties, corrects many of the metabolic disturbances linked to insulin resistance and represents a promising therapeutic approach for metabolic syndrome."
In the study one group of mice was fed a high-fat (western) diet to induce the symptoms of metabolic syndrome. A second group was fed the exact same diet and treated with naringenin. Naringenin corrected the elevations in triglyceride and cholesterol, prevented the development of insulin resistance and completely normalized glucose metabolism. The researchers found it worked by genetically reprogramming the liver to burn up excess fat, rather than store it.
"Furthermore, the marked obesity that develops in these mice was completely prevented by naringenin," says Huff, Director of the Vascular Biology Research Group at Robarts and Professor of Medicine and Biochemistry at the Schulich School of Medicine & Dentistry. "What was unique about the study was that the effects were independent of caloric intake, meaning the mice ate exactly the same amount of food and the same amount of fat. There was no suppression of appetite or decreased food intake, which are often the basis of strategies to reduce weight gain and its metabolic consequences."
While grapefruit has long been linked to weight loss diets, the concentrations of the citrus-derived flavonoid being studied are at higher levels than you could get from dietary components. "We are examining the pharmacological properties of naringenin," explains Huff. "The next step is to find out if naringenin prevents heart disease in animal models and to explore the feasibility of clinical trials to determine its safety and efficacy in humans."
This study investigated naringenin's preventative properties, but Huff is also investigating whether it can treat obesity and other existing metabolic problems. "These studies show naringenin, through its insulin-like properties, corrects many of the metabolic disturbances linked to insulin resistance and represents a promising therapeutic approach for metabolic syndrome."
Moderate alcohol intake has cognitive benefits
A glass of wine here, a nightcap there – new research out of Wake Forest University School of Medicine suggests that moderate alcohol intake offers long-term cognitive protection and reduces the risk of dementia in older adults.
The study is being presented at the Alzheimer's Association 2009 International Conference on Alzheimer's Disease (ICAD), in Vienna on July 13.
While previous studies have shown that moderate alcohol intake, particularly wine, is linked with lower risk of heart attacks and dementia, most of the studies have been done in middle-aged people, and it has remained unclear if the benefits of alcohol also apply to older adults in general or to older adults who might already have some mild memory problems. This is the largest, longest U.S. study to look at the effects of regular alcohol intake on dementia in seniors, both with and without memory problems.
"As of yet, we still have no cure for Alzheimer's disease and other dementias, so it is important to look for things that might help people prevent the disease," said Kaycee Sink, M.D., M.A.S (Masters of Advanced Studies in clinical research), a geriatrician and senior author of the paper. Moderate alcohol intake has been linked to lower risk of heart attacks, stroke, dementia, and death in middle-aged adults, but there is still controversy about alcohol intake in older adults."
For the study, researchers began by examining and interviewing 3,069 individuals, 75 years or older and most without any memory or thinking problems, about their drinking habits. Participants were asked about beer, wine, and liquor. The investigators then categorized the individuals as abstainers (non-drinkers), light drinkers (one to seven drinks per week), moderate drinkers (eight to 14 drinks per week), or heavy drinkers (more than 14 drinks per week). All types of alcohol were included.
The study subjects were then examined and interviewed every six months for six years to determine changes in their memory or thinking abilities and to monitor who developed dementia.
Researchers found that individuals who had no cognitive impairment at the start of the study and drank eight to 14 alcoholic beverages per week, or one to two per day, experienced an average 37 percent reduction in risk of developing dementia compared to individuals who did not drink at all and were classified as abstainers. The type of alcohol consumed did not matter.
For older adults who started the study with mild cognitive impairment, however, consumption of alcohol, at any amount, was associated with faster rates of cognitive decline. In addition, those who were classified in the heavy drinker category, consuming more than 14 drinks per week, were almost twice as likely to develop dementia during the study compared to non-drinkers with mild cognitive impairment.
"We were excited to see that even in older adults, moderate alcohol intake decreases the risk of dementia," Sink said. "It is important to note, however, that our study found a significantly higher risk of dementia for heavy drinkers who started the study with mild cognitive impairment."
The results are consistent with previous studies of middle-aged adults that suggest mild to moderate alcohol intake may reduce the risk of dementia, except in the case of individuals who already have mild to moderate cognitive impairment. The researchers' findings support current recommendations not to exceed one drink per day for women and two for men.
It is unclear from this study whether an abstainer who begins drinking moderately in his/her 70s will experience the same benefit or if the benefit is associated with a long pattern of moderate alcohol intake that continues on into old age.
"Our results suggest that older adults who are normal cognitively and drink moderately do not need to change their drinking behavior," Sink said. "If you have mild cognitive impairment however, it might benefit you to restrict your drinking and certainly not exceed one drink a day for women and two drinks a day for men.
"The participants in this study self-reported their alcohol intake at the start, but it is unusual for people to start drinking in their 70s, so we assume that the habits they reported at the start of the study reflect stable drinking habits," Sink added. "Without scientific data showing that it is beneficial, I wouldn't recommend that non-drinkers start drinking in their 70s.
"We are starting to make progress in understanding how to prevent and treat Alzheimer's and other dementias," she said. "It is a very exciting time to be involved in geriatrics research."
The study is being presented at the Alzheimer's Association 2009 International Conference on Alzheimer's Disease (ICAD), in Vienna on July 13.
While previous studies have shown that moderate alcohol intake, particularly wine, is linked with lower risk of heart attacks and dementia, most of the studies have been done in middle-aged people, and it has remained unclear if the benefits of alcohol also apply to older adults in general or to older adults who might already have some mild memory problems. This is the largest, longest U.S. study to look at the effects of regular alcohol intake on dementia in seniors, both with and without memory problems.
"As of yet, we still have no cure for Alzheimer's disease and other dementias, so it is important to look for things that might help people prevent the disease," said Kaycee Sink, M.D., M.A.S (Masters of Advanced Studies in clinical research), a geriatrician and senior author of the paper. Moderate alcohol intake has been linked to lower risk of heart attacks, stroke, dementia, and death in middle-aged adults, but there is still controversy about alcohol intake in older adults."
For the study, researchers began by examining and interviewing 3,069 individuals, 75 years or older and most without any memory or thinking problems, about their drinking habits. Participants were asked about beer, wine, and liquor. The investigators then categorized the individuals as abstainers (non-drinkers), light drinkers (one to seven drinks per week), moderate drinkers (eight to 14 drinks per week), or heavy drinkers (more than 14 drinks per week). All types of alcohol were included.
The study subjects were then examined and interviewed every six months for six years to determine changes in their memory or thinking abilities and to monitor who developed dementia.
Researchers found that individuals who had no cognitive impairment at the start of the study and drank eight to 14 alcoholic beverages per week, or one to two per day, experienced an average 37 percent reduction in risk of developing dementia compared to individuals who did not drink at all and were classified as abstainers. The type of alcohol consumed did not matter.
For older adults who started the study with mild cognitive impairment, however, consumption of alcohol, at any amount, was associated with faster rates of cognitive decline. In addition, those who were classified in the heavy drinker category, consuming more than 14 drinks per week, were almost twice as likely to develop dementia during the study compared to non-drinkers with mild cognitive impairment.
"We were excited to see that even in older adults, moderate alcohol intake decreases the risk of dementia," Sink said. "It is important to note, however, that our study found a significantly higher risk of dementia for heavy drinkers who started the study with mild cognitive impairment."
The results are consistent with previous studies of middle-aged adults that suggest mild to moderate alcohol intake may reduce the risk of dementia, except in the case of individuals who already have mild to moderate cognitive impairment. The researchers' findings support current recommendations not to exceed one drink per day for women and two for men.
It is unclear from this study whether an abstainer who begins drinking moderately in his/her 70s will experience the same benefit or if the benefit is associated with a long pattern of moderate alcohol intake that continues on into old age.
"Our results suggest that older adults who are normal cognitively and drink moderately do not need to change their drinking behavior," Sink said. "If you have mild cognitive impairment however, it might benefit you to restrict your drinking and certainly not exceed one drink a day for women and two drinks a day for men.
"The participants in this study self-reported their alcohol intake at the start, but it is unusual for people to start drinking in their 70s, so we assume that the habits they reported at the start of the study reflect stable drinking habits," Sink added. "Without scientific data showing that it is beneficial, I wouldn't recommend that non-drinkers start drinking in their 70s.
"We are starting to make progress in understanding how to prevent and treat Alzheimer's and other dementias," she said. "It is a very exciting time to be involved in geriatrics research."
Curcumin could reduce the cancer risk for women
Asian Spice Could Reduce Breast Cancer Risk in Postmenopausal Women Exposed to Hormone Replacement Therapy, MU Study Finds
Previous studies have found that postmenopausal women who have taken a combined estrogen and progestin hormone replacement therapy have increased their risk of developing progestin-accelerated breast tumors. Now, University of Missouri researchers have found that curcumin, a popular Indian spice derived from the turmeric root, could reduce the cancer risk for women after exposure to hormone replacement therapy.
"Approximately 6 million women in the United States use hormone replacement therapy to treat the symptoms of menopause," said Salman Hyder, the Zalk Endowed Professorship in Tumor Angiogenesis and professor of biomedical sciences in the College of Veterinary Medicine and the Dalton Cardiovascular Research Center. "This exposure to progestin will predispose a large number of post-menopausal women to future development of breast cancer. The results of our study show that women could potentially take curcumin to protect themselves from developing progestin-accelerated tumors."
In the study, researchers found that curcumin delayed the first appearance, decreased incidence and reduced multiplicity of progestin-accelerated tumors in an animal model. Curcumin also prevented the appearance of gross morphological abnormalities in the mammary glands. In previous studies, MU researchers showed that progestin accelerated the development of certain tumors by increasing production of a molecule called VEGF that helps supply blood to the tumor. By blocking the production of VEGF, researchers could potentially reduce the proliferation of breast cancer cells. Curcumin inhibits progestin-induced VEGF secretion from breast cancer cells, Hyder said.
"Curcumin and other potential anti-angiogenic compounds should be tested further as dietary chemopreventive agents in women already exposed to hormone replacement therapy containing estrogen and progestin in an effort to decrease or delay the risk of breast cancer associated with combined hormone replacement therapy," Hyder said.
The study, "Curcumin delays development of MPA-accelerated DMBA-induced mammary tumors," has been accepted for publication in Menopause, a journal of the North American Menopause Society. It was coauthored by Hyder; Candace Carroll, graduate student of biomedical sciences; Cynthia Besch-Williford, associate professor of veterinary pathobiology in the MU College of Veterinary Medicine; and Mark Ellersieck, professor and researcher in the MU Experiment Station Statistics.
Previous studies have found that postmenopausal women who have taken a combined estrogen and progestin hormone replacement therapy have increased their risk of developing progestin-accelerated breast tumors. Now, University of Missouri researchers have found that curcumin, a popular Indian spice derived from the turmeric root, could reduce the cancer risk for women after exposure to hormone replacement therapy.
"Approximately 6 million women in the United States use hormone replacement therapy to treat the symptoms of menopause," said Salman Hyder, the Zalk Endowed Professorship in Tumor Angiogenesis and professor of biomedical sciences in the College of Veterinary Medicine and the Dalton Cardiovascular Research Center. "This exposure to progestin will predispose a large number of post-menopausal women to future development of breast cancer. The results of our study show that women could potentially take curcumin to protect themselves from developing progestin-accelerated tumors."
In the study, researchers found that curcumin delayed the first appearance, decreased incidence and reduced multiplicity of progestin-accelerated tumors in an animal model. Curcumin also prevented the appearance of gross morphological abnormalities in the mammary glands. In previous studies, MU researchers showed that progestin accelerated the development of certain tumors by increasing production of a molecule called VEGF that helps supply blood to the tumor. By blocking the production of VEGF, researchers could potentially reduce the proliferation of breast cancer cells. Curcumin inhibits progestin-induced VEGF secretion from breast cancer cells, Hyder said.
"Curcumin and other potential anti-angiogenic compounds should be tested further as dietary chemopreventive agents in women already exposed to hormone replacement therapy containing estrogen and progestin in an effort to decrease or delay the risk of breast cancer associated with combined hormone replacement therapy," Hyder said.
The study, "Curcumin delays development of MPA-accelerated DMBA-induced mammary tumors," has been accepted for publication in Menopause, a journal of the North American Menopause Society. It was coauthored by Hyder; Candace Carroll, graduate student of biomedical sciences; Cynthia Besch-Williford, associate professor of veterinary pathobiology in the MU College of Veterinary Medicine; and Mark Ellersieck, professor and researcher in the MU Experiment Station Statistics.
Wednesday, July 8, 2009
The Benefits of Red Wine - Review
Benefits of all alcohol:
Studies on the use of alcohol have shown protective effects against coronary heart disease (CHD). These studies show that one or two alcoholic drinks per day increases high-density lipoprotein (HDL) cholesterol. Also, moderate alcohol consumption decreases low-density lipoprotein (LDL) cholesterol and triglycerides. Finally, alcohol consumption decreases platelet aggregation.
Benefits of Red Wine
There has been some discussion recently, including an article in the New York Times, pointing out that there is a difference in lifestyle among people who drink wine, beer, and other alcoholic beverages, including social class and diet, that may also explain why wine seems to offer more protection than others against coronary heart disease. (1)
Regardless, wine, especially red wine, really does seem to have benefits that the other sources of alcohol do not have, including:
REDUCES INFLAMMATION
Red wine may have anti-inflammatory effects. It reduces C-reactive protein, a marker of inflammation that seems to be related to atherosclerosis. (2)
ANTIOXIDANT PROPERTIES
Red wine has higher concentrations of antioxidant molecules, called polyphenols, than other alcoholic drinks. The antioxidant properties of these polyphenols may contribute to protection against coronary heart disease by reducing oxidation of LDL cholesterol. (3) The polyphenols in red wine include anthocyanins, proanthocyanidins, and resveratrol, and flavonoids, including catechins, kaempferol, and quercetin. (4,5) However, the polyphenol content of wine is dependent upon grape variety, climate, and the methods used to make the wine. White wines, unlike red wines, have very low polyphenol concentrations.
IMMUNE SUPPORT
Red wine may also reduce mutagenic DNA damage and improve endothelial function when included in a high fat diet. (6) Wine can stimulate gastric acid secretion and gastrin release. This may explain why moderate to high wine intake seems to prevent Helicobacter pylori infection. (7) Finally, the anthocyanins in red wine may help prevent various cancers. (8)
OTHER BENEFITS
Red wine may help to prevent noise-induced hearing loss (9), reduce the risk of developing age-related macular degeneration (10), may help to prevent cataracts (11), and may help to prevent rheumatoid arthritis (12).
REFERENCES
1. Rimm EB, Stampfer MJ. Wine, beer, and spirits: are they really horses of a different color? Circulation 2002;105:2806-7.
2. Estruch R, Sacanella E, Badia E, et al. Different effects of red wine and gin consumption on inflammatory biomarkers of atherosclerosis: a prospective randomized crossover trial. Effects of wine on inflammatory markers. Atherosclerosis 2004;175:117-23.
3. Klatsky AL, Armstrong MA, Friedman GD. Red wine, white wine, liquor, beer, and risk for coronary artery disease hospitalization. Am J Cardiol 1997;80:416-20.
4. Caccetta RA, Croft KD, Beilin LJ, Puddey IB. Ingestion of red wine significantly increases plasma phenolic acid concentrations but does not acutely affect ex vivo lipoprotein oxidizability. Am J Clin Nutr 2000;71:67-74.
5. Soleas GJ, Diamandis EP, Goldberg DM. Wine as a biological fluid: history, production, and role in disease prevention. J Clin Lab Anal 1997;11:287-313.
6. Leighton F, Cuevas A, Guasch V, et al. Plasma polyphenols and antioxidants, oxidative DNA damage and endothelial function in a diet and wine intervention study in humans. Drugs Exp Clin Res 1999;25:133-41.
7. Brenner H, Rothenbacher D, Bode G, Adler G. Relation of smoking and alcohol and coffee consumption to active Helicobacter pylori infection: cross sectional study. BMJ 1997;315:1489-92.
8. Hou, D. X. Potential mechanisms of cancer chemoprevention by anthocyanins. Curr Mol Med. 3(2):149-159, 2003.
9. Seidman, M., et al. Effects of resveratrol on acoustic trauma. Otolaryngol Head Neck Surg. 129(5):463-470, 2003.
10. Obisesan, T.O., et al. Moderate wine consumption is associated with decreased odds of developing age-related macular degeneration in NHANES-1. J Am Geriatr Soc. 46:1-7, 1998.
11. Jonasson, F., et al. Abstract B198: Moderate red wine drinking reduces risk for cataract. Annual Meeting of the Association for Research in Vision and Ophthalmology. Fort Lauderdale, USA. May 4, 2005.
12. Kallberg, H., et al. Alcohol consumption is associated with decreased risk of rheumatoid arthritis; Results from two Scandinavian case-control studies. Ann Rheum Dis. 2008.
Studies on the use of alcohol have shown protective effects against coronary heart disease (CHD). These studies show that one or two alcoholic drinks per day increases high-density lipoprotein (HDL) cholesterol. Also, moderate alcohol consumption decreases low-density lipoprotein (LDL) cholesterol and triglycerides. Finally, alcohol consumption decreases platelet aggregation.
Benefits of Red Wine
There has been some discussion recently, including an article in the New York Times, pointing out that there is a difference in lifestyle among people who drink wine, beer, and other alcoholic beverages, including social class and diet, that may also explain why wine seems to offer more protection than others against coronary heart disease. (1)
Regardless, wine, especially red wine, really does seem to have benefits that the other sources of alcohol do not have, including:
REDUCES INFLAMMATION
Red wine may have anti-inflammatory effects. It reduces C-reactive protein, a marker of inflammation that seems to be related to atherosclerosis. (2)
ANTIOXIDANT PROPERTIES
Red wine has higher concentrations of antioxidant molecules, called polyphenols, than other alcoholic drinks. The antioxidant properties of these polyphenols may contribute to protection against coronary heart disease by reducing oxidation of LDL cholesterol. (3) The polyphenols in red wine include anthocyanins, proanthocyanidins, and resveratrol, and flavonoids, including catechins, kaempferol, and quercetin. (4,5) However, the polyphenol content of wine is dependent upon grape variety, climate, and the methods used to make the wine. White wines, unlike red wines, have very low polyphenol concentrations.
IMMUNE SUPPORT
Red wine may also reduce mutagenic DNA damage and improve endothelial function when included in a high fat diet. (6) Wine can stimulate gastric acid secretion and gastrin release. This may explain why moderate to high wine intake seems to prevent Helicobacter pylori infection. (7) Finally, the anthocyanins in red wine may help prevent various cancers. (8)
OTHER BENEFITS
Red wine may help to prevent noise-induced hearing loss (9), reduce the risk of developing age-related macular degeneration (10), may help to prevent cataracts (11), and may help to prevent rheumatoid arthritis (12).
REFERENCES
1. Rimm EB, Stampfer MJ. Wine, beer, and spirits: are they really horses of a different color? Circulation 2002;105:2806-7.
2. Estruch R, Sacanella E, Badia E, et al. Different effects of red wine and gin consumption on inflammatory biomarkers of atherosclerosis: a prospective randomized crossover trial. Effects of wine on inflammatory markers. Atherosclerosis 2004;175:117-23.
3. Klatsky AL, Armstrong MA, Friedman GD. Red wine, white wine, liquor, beer, and risk for coronary artery disease hospitalization. Am J Cardiol 1997;80:416-20.
4. Caccetta RA, Croft KD, Beilin LJ, Puddey IB. Ingestion of red wine significantly increases plasma phenolic acid concentrations but does not acutely affect ex vivo lipoprotein oxidizability. Am J Clin Nutr 2000;71:67-74.
5. Soleas GJ, Diamandis EP, Goldberg DM. Wine as a biological fluid: history, production, and role in disease prevention. J Clin Lab Anal 1997;11:287-313.
6. Leighton F, Cuevas A, Guasch V, et al. Plasma polyphenols and antioxidants, oxidative DNA damage and endothelial function in a diet and wine intervention study in humans. Drugs Exp Clin Res 1999;25:133-41.
7. Brenner H, Rothenbacher D, Bode G, Adler G. Relation of smoking and alcohol and coffee consumption to active Helicobacter pylori infection: cross sectional study. BMJ 1997;315:1489-92.
8. Hou, D. X. Potential mechanisms of cancer chemoprevention by anthocyanins. Curr Mol Med. 3(2):149-159, 2003.
9. Seidman, M., et al. Effects of resveratrol on acoustic trauma. Otolaryngol Head Neck Surg. 129(5):463-470, 2003.
10. Obisesan, T.O., et al. Moderate wine consumption is associated with decreased odds of developing age-related macular degeneration in NHANES-1. J Am Geriatr Soc. 46:1-7, 1998.
11. Jonasson, F., et al. Abstract B198: Moderate red wine drinking reduces risk for cataract. Annual Meeting of the Association for Research in Vision and Ophthalmology. Fort Lauderdale, USA. May 4, 2005.
12. Kallberg, H., et al. Alcohol consumption is associated with decreased risk of rheumatoid arthritis; Results from two Scandinavian case-control studies. Ann Rheum Dis. 2008.
High Protein Diets Threaten Bones and Muscles
"Alkali Load" May Help Conserve Bone and Muscle
Agricultural Research Service (ARS)-funded scientists have recently reported that compounds in plant foods, which are alkali-producing, may help preserve bone and muscle mass. Now, a new ARS-funded study suggests that reducing the acid load that accompanies the typical high protein diet may also be important.
Diets high in protein and low in fruits and vegetables result in mild "acidosis" with aging. That's because protein metabolism releases acids into the bloodstream in amounts that override the alkalinizing effect of potassium and bicarbonate in plant foods.
The researchers studied results from a group of 19 healthy individuals, older than 50, who were on a controlled diet. To simulate consumption of the equivalent of eating about 14 servings of fruits and vegetables daily, nine of the participants were randomly assigned to receive 3,510 milligrams daily of potassium bicarbonate in capsules. The other 10 participants were assigned to receive matching "placebo" capsules.
Once the volunteers gradually reached the maximal level of daily potassium bicarbonate or placebo capsules, all 19 participants were successively given a 10-day low (or high) protein diet followed by a 10-day high (or low) protein diet, with a five-day “wash out” period in between.
The researchers wanted to look at both an alkali-producing diet (the potassium bicarbonate group) and an acid-producing diet (the placebo group). Blood, urine and calcium absorption analyses were performed after each diet period, and markers of muscle and bone metabolism were measured.
With increased dietary protein intake, the potassium bicarbonate, or alkalinized, group--when compared to the placebo group--had reduced urinary nitrogen excretion, which is an indicator of reduced muscle wasting. The alkalinized group also had higher levels of IGF-1, a marker of both muscle and bone conservation, and of calcium absorption--a marker of bone conservation--on both protein diets, compared to the placebo group.
The study suggests that the net effect of adequate dietary protein on muscle may be enhanced by reducing its accompanying acid load, according to the authors. Though not tested in the study, increasing intake of fruits and vegetables would be another way to increase the alkali potential of the diet, according to Dawson-Hughes.
Another study produced similar results:
Fruits and vegetables are metabolized to bicarbonate and thus are alkali-producing. But the typical American diet is rich in protein and cereal grains that are metabolized to acid, and thus are acid-producing. With aging, such diets lead to a mild but slowly increasing metabolic "acidosis."
The researchers conducted a placebo-controlled study involving healthy male and female volunteers aged 50 or older. Key measurements were taken at the beginning and end of the intervention, which lasted three months.
A group of 78 volunteers had been provided either of two bicarbonates—potassium or sodium—along with their usual diet and exercise regimes. Key bone mineral nutrients were controlled to reduce variation in study outcomes. The bicarbonate groups consumed an amount of bicarbonate equivalent to about 9 servings of fruits and vegetables daily. This allowed the researchers to look at possible acid-neutralizing effects from an adequate, not high, alkali load.
The results showed that the 78 volunteers in the bicarbonate groups had significant reductions in biomarkers that are associated with bone loss and fracture than the 84 in the no-bicarbonate, or control, group.
The authors concluded that increasing the alkali content of the diet, for example by consuming more fruits and vegetables, merits further study as a safe and low-cost approach to improving skeletal health in older men and women.
Agricultural Research Service (ARS)-funded scientists have recently reported that compounds in plant foods, which are alkali-producing, may help preserve bone and muscle mass. Now, a new ARS-funded study suggests that reducing the acid load that accompanies the typical high protein diet may also be important.
Diets high in protein and low in fruits and vegetables result in mild "acidosis" with aging. That's because protein metabolism releases acids into the bloodstream in amounts that override the alkalinizing effect of potassium and bicarbonate in plant foods.
The researchers studied results from a group of 19 healthy individuals, older than 50, who were on a controlled diet. To simulate consumption of the equivalent of eating about 14 servings of fruits and vegetables daily, nine of the participants were randomly assigned to receive 3,510 milligrams daily of potassium bicarbonate in capsules. The other 10 participants were assigned to receive matching "placebo" capsules.
Once the volunteers gradually reached the maximal level of daily potassium bicarbonate or placebo capsules, all 19 participants were successively given a 10-day low (or high) protein diet followed by a 10-day high (or low) protein diet, with a five-day “wash out” period in between.
The researchers wanted to look at both an alkali-producing diet (the potassium bicarbonate group) and an acid-producing diet (the placebo group). Blood, urine and calcium absorption analyses were performed after each diet period, and markers of muscle and bone metabolism were measured.
With increased dietary protein intake, the potassium bicarbonate, or alkalinized, group--when compared to the placebo group--had reduced urinary nitrogen excretion, which is an indicator of reduced muscle wasting. The alkalinized group also had higher levels of IGF-1, a marker of both muscle and bone conservation, and of calcium absorption--a marker of bone conservation--on both protein diets, compared to the placebo group.
The study suggests that the net effect of adequate dietary protein on muscle may be enhanced by reducing its accompanying acid load, according to the authors. Though not tested in the study, increasing intake of fruits and vegetables would be another way to increase the alkali potential of the diet, according to Dawson-Hughes.
Another study produced similar results:
Fruits and vegetables are metabolized to bicarbonate and thus are alkali-producing. But the typical American diet is rich in protein and cereal grains that are metabolized to acid, and thus are acid-producing. With aging, such diets lead to a mild but slowly increasing metabolic "acidosis."
The researchers conducted a placebo-controlled study involving healthy male and female volunteers aged 50 or older. Key measurements were taken at the beginning and end of the intervention, which lasted three months.
A group of 78 volunteers had been provided either of two bicarbonates—potassium or sodium—along with their usual diet and exercise regimes. Key bone mineral nutrients were controlled to reduce variation in study outcomes. The bicarbonate groups consumed an amount of bicarbonate equivalent to about 9 servings of fruits and vegetables daily. This allowed the researchers to look at possible acid-neutralizing effects from an adequate, not high, alkali load.
The results showed that the 78 volunteers in the bicarbonate groups had significant reductions in biomarkers that are associated with bone loss and fracture than the 84 in the no-bicarbonate, or control, group.
The authors concluded that increasing the alkali content of the diet, for example by consuming more fruits and vegetables, merits further study as a safe and low-cost approach to improving skeletal health in older men and women.
Walnuts Improve Performance
Dietary Intervention Shows Neuroprotection
Adding a moderate, but not high, amount of walnuts to an otherwise healthy diet may help older individuals improve performance on tasks that require motor and behavioral skills, according to an animal model study by Agricultural Research Service (ARS)-funded scientists. Walnuts contain polyphenols and other antioxidants and essential fatty acids.
The aging brain undergoes many changes that can result in altered or impaired neuronal functioning. Such disruption can be attributed in part to alterations in "synaptic plasticity," or the ability of the connections between neurons to change in strength and function, and also by increased oxidative damage to neural tissue. In aged rodents, these impairments are seen as poor performance on age-sensitive tests of balance, coordination, and "spatial" working memory.
For the study, weight-matched, aged rats were randomly assigned to one of four diet groups. For eight weeks, the rats were fed special chow mixes that contained either 2 percent, 6 percent or 9 percent walnuts-or no walnuts-before undergoing motor and memory tests. For comparison, the 6 percent walnut study diet is equivalent to a human eating 1 ounce, or about 7 to 9 walnuts, a day. That counts as both a 2-ounce equivalent from the "meat and beans group" and 2 teaspoons toward a daily allowance of dietary oil, as described at MyPyramid.gov.
The study found that in aged rats, the diets containing 2 percent or 6 percent walnuts were able to improve age-related motor and cognitive shortfalls, while the 9 percent walnut diet impaired reference memory. Walnuts, eaten in moderation, appear to be among other foods containing polyphenols and bioactive substances that exhibit multiple effects on neural tissue, according to the researchers.
Adding a moderate, but not high, amount of walnuts to an otherwise healthy diet may help older individuals improve performance on tasks that require motor and behavioral skills, according to an animal model study by Agricultural Research Service (ARS)-funded scientists. Walnuts contain polyphenols and other antioxidants and essential fatty acids.
The aging brain undergoes many changes that can result in altered or impaired neuronal functioning. Such disruption can be attributed in part to alterations in "synaptic plasticity," or the ability of the connections between neurons to change in strength and function, and also by increased oxidative damage to neural tissue. In aged rodents, these impairments are seen as poor performance on age-sensitive tests of balance, coordination, and "spatial" working memory.
For the study, weight-matched, aged rats were randomly assigned to one of four diet groups. For eight weeks, the rats were fed special chow mixes that contained either 2 percent, 6 percent or 9 percent walnuts-or no walnuts-before undergoing motor and memory tests. For comparison, the 6 percent walnut study diet is equivalent to a human eating 1 ounce, or about 7 to 9 walnuts, a day. That counts as both a 2-ounce equivalent from the "meat and beans group" and 2 teaspoons toward a daily allowance of dietary oil, as described at MyPyramid.gov.
The study found that in aged rats, the diets containing 2 percent or 6 percent walnuts were able to improve age-related motor and cognitive shortfalls, while the 9 percent walnut diet impaired reference memory. Walnuts, eaten in moderation, appear to be among other foods containing polyphenols and bioactive substances that exhibit multiple effects on neural tissue, according to the researchers.
Dietary curcumin could stall the spread of fat-tissue
Benefits of Compound in Turmeric Spice Studied
There may be a new way to spice up your weight loss routine, according to results from a new animal model study by Agricultural Research Service (ARS)-funded scientists and colleagues.
The researchers theorized that dietary curcumin could stall the spread of fat-tissue by inhibiting new blood vessel growth, called angiogenesis, which is necessary to build fat tissue. Curcumin is a bioactive component in curry and turmeric that has been consumed daily in Asian countries for centuries without reported toxic effects.
The study was led by nutritionist Mohsen Meydani at the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts University in Boston, Mass. Meydani is director of the HNRCA's Vascular Biology Laboratory.
Eighteen mice were assigned to three groups of six mice each. For 12 weeks, the mice were fed special diets. A “control” group’s mix contained 4 percent fat, a “high fat” group’s mix contained 22 percent fat, and another group was fed the same “high fat” diet supplemented with curcumin. A mouse typically eats about 3,000 to 3,500 milligrams (the weight of about six or seven paper clips) daily, so the curcumin-supplemented mice would have consumed about 1.5 to 1.75 milligrams of curcumin daily—a relatively small amount.
The researchers recorded the body weight and food consumption of the mice twice each week. At the end of the 12-week period, their total body weight and fat distribution were measured.
The study found that supplementing the animals’ high-fat diet with curcumin reduced body-weight gain and total body fat, even though food-intake was not affected, when compared to the nonsupplemented high-fat-diet group.
The curcumin-treated group also had less blood vessel growth in fat tissue. Blood glucose, triglyceride, fatty acid, cholesterol and liver fat levels also were lower.
At this time, it is not known whether the amount of curcumin normally present in food dishes prepared with turmeric is sufficient to inhibit complex fat-tissue secretions that are involved in recruiting new blood vessel growth. The researchers’ next step is to determine the effectiveness of dietary intake of curcumin in reducing weight in humans.
There may be a new way to spice up your weight loss routine, according to results from a new animal model study by Agricultural Research Service (ARS)-funded scientists and colleagues.
The researchers theorized that dietary curcumin could stall the spread of fat-tissue by inhibiting new blood vessel growth, called angiogenesis, which is necessary to build fat tissue. Curcumin is a bioactive component in curry and turmeric that has been consumed daily in Asian countries for centuries without reported toxic effects.
The study was led by nutritionist Mohsen Meydani at the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts University in Boston, Mass. Meydani is director of the HNRCA's Vascular Biology Laboratory.
Eighteen mice were assigned to three groups of six mice each. For 12 weeks, the mice were fed special diets. A “control” group’s mix contained 4 percent fat, a “high fat” group’s mix contained 22 percent fat, and another group was fed the same “high fat” diet supplemented with curcumin. A mouse typically eats about 3,000 to 3,500 milligrams (the weight of about six or seven paper clips) daily, so the curcumin-supplemented mice would have consumed about 1.5 to 1.75 milligrams of curcumin daily—a relatively small amount.
The researchers recorded the body weight and food consumption of the mice twice each week. At the end of the 12-week period, their total body weight and fat distribution were measured.
The study found that supplementing the animals’ high-fat diet with curcumin reduced body-weight gain and total body fat, even though food-intake was not affected, when compared to the nonsupplemented high-fat-diet group.
The curcumin-treated group also had less blood vessel growth in fat tissue. Blood glucose, triglyceride, fatty acid, cholesterol and liver fat levels also were lower.
At this time, it is not known whether the amount of curcumin normally present in food dishes prepared with turmeric is sufficient to inhibit complex fat-tissue secretions that are involved in recruiting new blood vessel growth. The researchers’ next step is to determine the effectiveness of dietary intake of curcumin in reducing weight in humans.
Monday, July 6, 2009
Eating vegetables lowers blood pressure
Component of vegetable protein may be linked to lower blood pressure
Consuming an amino acid commonly found in vegetable protein may be associated with lower blood pressure, researchers report in Circulation: Journal of the American Heart Association.
Researchers found that a 4.72 percent higher dietary intake of the amino acid glutamic acid as a percent of total dietary protein correlated with lower group average systolic blood pressure, lower by 1.5 to 3.0 millimeters of mercury (mm Hg). Group average diastolic blood pressure was lower by 1.0 to 1.6 mm Hg.
Systolic blood pressure is the force when the heart beats; diastolic pressure is the pressure when the heart rests between beats.
This average lower blood pressure seems small from an individual perspective. But, on a population scale, it represents a potentially important reduction, said Jeremiah Stamler, M.D., lead author of the study.
"It is estimated that reducing a population's average systolic blood pressure by 2 mm Hg could cut stroke death rates by 6 percent and reduce mortality from coronary heart disease by 4 percent," said Stamler, professor emeritus of the Department of Preventive Medicine in the Feinberg School of Medicine at Northwestern University in Chicago, Ill.
Based on American Heart Association 2009 statistics, 6 percent of stroke deaths would be more than 8,600 people and four percent of coronary heart deaths represents about 17,800 lives saved per year.
"High blood pressure is a major cardiovascular disease risk factor, and blood pressure tends to rise with age starting early in life so that the majority of the U.S. population age 35 and older is affected by pre-hypertension or hypertension," he said. "We have a massive public health problem, and trying to address it by the strategy that has prevailed for years — diagnosis and drug treatment — is inadequate. While clinically useful, it fails as a long-term approach for ending this massive problem."
The only long-term approach is to prevent pre-hypertension and hypertension by improved lifestyle behaviors, Stamler said. This includes maintaining a healthy body weight, having a fruit and vegetable-rich eating pattern and participating in regular physical activity. His previous study, INTERSALT, was instrumental in helping show that high-salt diets contribute to high blood pressure.
In the current study, researchers examined dietary amino acids, the building blocks of protein. Glutamic acid is the most common amino acid and accounts for almost a quarter (23 percent) of the protein in vegetable protein and almost one fifth (18 percent) of animal protein, Stamler said.
Researchers analyzed data from the International Study on Macro/Micronutrients and Blood Pressure (INTERMAP), on 4,680 people in 17 rural and urban populations in China, Japan, the United Kingdom and the United States. INTERMAP is a basic population study aiming to clarify the role of multiple nutrients in the etiology of unfavorable blood pressure patterns prevailing for most middle-aged and older individuals. Stamler and colleagues analyzed data from eight blood pressure tests, four diet recall surveys and two 24-hour urine collections for each participant.
"Although our research group and others earlier reported an association between higher consumption of vegetable protein and lower blood pressure, as far as we know this is the first paper on the relation of glutamic acid intake to blood pressure," said Ian J. Brown, Ph.D., co-author of the study and a research associate in the Department of Epidemiology and Public Health at Imperial College London.
Common sources of vegetable protein include beans, whole grains — including whole grain rice, pasta, breads and cereals — and soy products such as tofu. Durum wheat, which is used to make pasta, is also a good source of vegetable protein.
Stamler noted that there are no data on the possible effects of glutamic acid supplements and emphasized the importance of "improved habitual food intake for the prevention and control of hypertension, not popping pills."
Stamler said the INTERMAP Study may help explain on a molecular level why the Dieatary Approaches to Stop Hypertension (DASH) diet lowers blood pressure. The DASH eating pattern, developed by the U.S. National Institutes of Health, is rich in fruits, vegetables and low-fat and nonfat dairy products as well as whole grains, lean poultry, nuts and beans. The pattern is recommended by the American Heart Association and the National Heart, Lung, and Blood Institute, the key sponsor of the INTERMAP study.
"The DASH eating pattern resembles the Mediterranean eating style for the 21st century, including reduced salt intake," Stamler noted. "Multiple modifications supply multiple nutrients helpful for the prevention and control of high blood pressure, including glutamic acid.
Although the current study examined just one element in the dietary mix, amino acids, Stamler said there's no one "magic bullet."
Consuming an amino acid commonly found in vegetable protein may be associated with lower blood pressure, researchers report in Circulation: Journal of the American Heart Association.
Researchers found that a 4.72 percent higher dietary intake of the amino acid glutamic acid as a percent of total dietary protein correlated with lower group average systolic blood pressure, lower by 1.5 to 3.0 millimeters of mercury (mm Hg). Group average diastolic blood pressure was lower by 1.0 to 1.6 mm Hg.
Systolic blood pressure is the force when the heart beats; diastolic pressure is the pressure when the heart rests between beats.
This average lower blood pressure seems small from an individual perspective. But, on a population scale, it represents a potentially important reduction, said Jeremiah Stamler, M.D., lead author of the study.
"It is estimated that reducing a population's average systolic blood pressure by 2 mm Hg could cut stroke death rates by 6 percent and reduce mortality from coronary heart disease by 4 percent," said Stamler, professor emeritus of the Department of Preventive Medicine in the Feinberg School of Medicine at Northwestern University in Chicago, Ill.
Based on American Heart Association 2009 statistics, 6 percent of stroke deaths would be more than 8,600 people and four percent of coronary heart deaths represents about 17,800 lives saved per year.
"High blood pressure is a major cardiovascular disease risk factor, and blood pressure tends to rise with age starting early in life so that the majority of the U.S. population age 35 and older is affected by pre-hypertension or hypertension," he said. "We have a massive public health problem, and trying to address it by the strategy that has prevailed for years — diagnosis and drug treatment — is inadequate. While clinically useful, it fails as a long-term approach for ending this massive problem."
The only long-term approach is to prevent pre-hypertension and hypertension by improved lifestyle behaviors, Stamler said. This includes maintaining a healthy body weight, having a fruit and vegetable-rich eating pattern and participating in regular physical activity. His previous study, INTERSALT, was instrumental in helping show that high-salt diets contribute to high blood pressure.
In the current study, researchers examined dietary amino acids, the building blocks of protein. Glutamic acid is the most common amino acid and accounts for almost a quarter (23 percent) of the protein in vegetable protein and almost one fifth (18 percent) of animal protein, Stamler said.
Researchers analyzed data from the International Study on Macro/Micronutrients and Blood Pressure (INTERMAP), on 4,680 people in 17 rural and urban populations in China, Japan, the United Kingdom and the United States. INTERMAP is a basic population study aiming to clarify the role of multiple nutrients in the etiology of unfavorable blood pressure patterns prevailing for most middle-aged and older individuals. Stamler and colleagues analyzed data from eight blood pressure tests, four diet recall surveys and two 24-hour urine collections for each participant.
"Although our research group and others earlier reported an association between higher consumption of vegetable protein and lower blood pressure, as far as we know this is the first paper on the relation of glutamic acid intake to blood pressure," said Ian J. Brown, Ph.D., co-author of the study and a research associate in the Department of Epidemiology and Public Health at Imperial College London.
Common sources of vegetable protein include beans, whole grains — including whole grain rice, pasta, breads and cereals — and soy products such as tofu. Durum wheat, which is used to make pasta, is also a good source of vegetable protein.
Stamler noted that there are no data on the possible effects of glutamic acid supplements and emphasized the importance of "improved habitual food intake for the prevention and control of hypertension, not popping pills."
Stamler said the INTERMAP Study may help explain on a molecular level why the Dieatary Approaches to Stop Hypertension (DASH) diet lowers blood pressure. The DASH eating pattern, developed by the U.S. National Institutes of Health, is rich in fruits, vegetables and low-fat and nonfat dairy products as well as whole grains, lean poultry, nuts and beans. The pattern is recommended by the American Heart Association and the National Heart, Lung, and Blood Institute, the key sponsor of the INTERMAP study.
"The DASH eating pattern resembles the Mediterranean eating style for the 21st century, including reduced salt intake," Stamler noted. "Multiple modifications supply multiple nutrients helpful for the prevention and control of high blood pressure, including glutamic acid.
Although the current study examined just one element in the dietary mix, amino acids, Stamler said there's no one "magic bullet."
Wednesday, July 1, 2009
Well-planned vegetarian diets are healthful
DA releases updated position paper on vegetarian diets
The American Dietetic Association has released an updated position paper on vegetarian diets that concludes such diets, if well-planned, are healthful and nutritious for adults, infants, children and adolescents and can help prevent and treat chronic diseases including heart disease, cancer, obesity and diabetes.
ADA's position, published in the July issue of the Journal of the American Dietetic Association, represents the Association's official stance on vegetarian diets:
"It is the position of the American Dietetic Association that appropriately planned vegetarian diets, including total vegetarian or vegan diets, are healthful, nutritionally adequate and may provide health benefits in the prevention and treatment of certain diseases. Well-planned vegetarian diets are appropriate for individuals during all stages of the life-cycle including pregnancy, lactation, infancy, childhood and adolescence and for athletes."
ADA's position and accompanying paper were written by Winston Craig, PhD, MPH, RD, professor and chair of the department of nutrition and wellness at Andrews University; and Reed Mangels, PhD, RD, nutrition advisor at the Vegetarian Resource Group, Baltimore, Md.
The revised position paper incorporates new topics and additional information on key nutrients for vegetarians, vegetarian diets in the life cycle and the use of vegetarian diets in prevention and treatment of chronic diseases. "Vegetarian diets are appropriate for all stages of the life cycle," according to ADA's position. "There are many reasons for the rising interest in vegetarian diets. The number of vegetarians in the United States is expected to increase over the next decade."
Vegetarian diets are often associated with health advantages including lower blood cholesterol levels, lower risk of heart disease, lower blood pressure levels and lower risk of hypertension and type 2 diabetes, according to ADA's position. "Vegetarians tend to have a lower body mass index and lower overall cancer rates. Vegetarian diets tend to be lower in saturated fat and cholesterol and have higher levels of dietary fiber, magnesium and potassium, vitamins C and E, folate, carotenoids, flavonoids and other phytochemicals. These nutritional differences may explain some of the health advantages of those following a varied, balanced vegetarian diet."
The position paper draws on results from ADA's evidence analysis process and information from the ADA Evidence Analysis Library to show vegetarian diets can be nutritionally adequate in pregnancy and result in positive maternal and infant health outcomes. Additionally, an evidence-based review showed a vegetarian diet is associated with a lower risk of death from ischemic heart disease.
A section in ADA's paper on vegetarian diets and cancer has been significantly expanded to provide details on cancer-protective factors in vegetarian diets. An expanded section on osteoporosis includes roles of fruits, vegetables, soy products, protein, calcium, vitamins D and K and potassium in bone health. "Registered dietitians can provide information about key nutrients, modify vegetarian diets to meet the needs of those with dietary restrictions due to disease or allergies and supply guidelines to meet needs of clients in different areas of the life cycle," the authors said.
The American Dietetic Association has released an updated position paper on vegetarian diets that concludes such diets, if well-planned, are healthful and nutritious for adults, infants, children and adolescents and can help prevent and treat chronic diseases including heart disease, cancer, obesity and diabetes.
ADA's position, published in the July issue of the Journal of the American Dietetic Association, represents the Association's official stance on vegetarian diets:
"It is the position of the American Dietetic Association that appropriately planned vegetarian diets, including total vegetarian or vegan diets, are healthful, nutritionally adequate and may provide health benefits in the prevention and treatment of certain diseases. Well-planned vegetarian diets are appropriate for individuals during all stages of the life-cycle including pregnancy, lactation, infancy, childhood and adolescence and for athletes."
ADA's position and accompanying paper were written by Winston Craig, PhD, MPH, RD, professor and chair of the department of nutrition and wellness at Andrews University; and Reed Mangels, PhD, RD, nutrition advisor at the Vegetarian Resource Group, Baltimore, Md.
The revised position paper incorporates new topics and additional information on key nutrients for vegetarians, vegetarian diets in the life cycle and the use of vegetarian diets in prevention and treatment of chronic diseases. "Vegetarian diets are appropriate for all stages of the life cycle," according to ADA's position. "There are many reasons for the rising interest in vegetarian diets. The number of vegetarians in the United States is expected to increase over the next decade."
Vegetarian diets are often associated with health advantages including lower blood cholesterol levels, lower risk of heart disease, lower blood pressure levels and lower risk of hypertension and type 2 diabetes, according to ADA's position. "Vegetarians tend to have a lower body mass index and lower overall cancer rates. Vegetarian diets tend to be lower in saturated fat and cholesterol and have higher levels of dietary fiber, magnesium and potassium, vitamins C and E, folate, carotenoids, flavonoids and other phytochemicals. These nutritional differences may explain some of the health advantages of those following a varied, balanced vegetarian diet."
The position paper draws on results from ADA's evidence analysis process and information from the ADA Evidence Analysis Library to show vegetarian diets can be nutritionally adequate in pregnancy and result in positive maternal and infant health outcomes. Additionally, an evidence-based review showed a vegetarian diet is associated with a lower risk of death from ischemic heart disease.
A section in ADA's paper on vegetarian diets and cancer has been significantly expanded to provide details on cancer-protective factors in vegetarian diets. An expanded section on osteoporosis includes roles of fruits, vegetables, soy products, protein, calcium, vitamins D and K and potassium in bone health. "Registered dietitians can provide information about key nutrients, modify vegetarian diets to meet the needs of those with dietary restrictions due to disease or allergies and supply guidelines to meet needs of clients in different areas of the life cycle," the authors said.
Diets high in protein& cholesterol = liver cancer risk
Study Examines Dietary Influences Of Liver Disease
Diets high in protein and cholesterol are associated with a higher risk of hospitalization or death due to cirrhosis or liver cancer, while diets high in carbohydrates are associated with a lower risk. These findings are in the July issue of Hepatology, a journal published by John Wiley & Sons on behalf of the American Association for the Study of Liver Diseases (AASLD). The article is also available online at Wiley Interscience (www.interscience.wiley.com).
There are many reasons to suspect that dietary factors influence the development of hepatic steatosis and its progression to more severe liver disease. First, poor diet may lead to obesity, insulin resistance and diabetes, which are the most important known risk factors for hepatic steatosis. Also, dietary lipids may directly affect fat in the liver. Furthermore, a high cholesterol diet has been shown to induce serious steatosis in animal studies.
Researchers, led by George Ioannou of Veterans Affairs Puget Sound Health Care System in Seattle, investigated whether dietary nutrient composition was associated with the subsequent development of cirrhosis or liver cancer in a representative sample of the U.S. population. They utilized data from 9,221 participants in the National Health Examination Survey who had completed a 24-hour dietary recall questionnaire. Participants were excluded if they suffered from cirrhosis or liver cancer at the start of the study, or received a diagnosis within five years.
During the follow-up period, an average of 13.3 years, 123 participants received a new diagnosis of cirrhosis (118 people) or liver cancer (5 people) according to hospitalization records and death certificates. These individuals were more likely to be older, more obese with more central fat distribution. They had lower educational attainment and higher alcohol consumption, and were more likely to be male, diabetic and non-white.
Dietary nutrient composition was a strong predictor of hospitalization or death due to cirrhosis or liver cancer in the U.S. population. “In particular, we identified that protein and cholesterol consumption were associated with elevated risk, whereas consumption of carbohydrates was associated with reduced risk of hospitalization or death related to cirrhosis or liver cancer,” the authors report.
The association with cholesterol intake is potentially the most important finding of this study, the authors suggest. While cholesterol is well-known for its role in non-hepatic diseases like atherosclerosis, it has never before been linked to human liver disease. The findings suggest that drugs blocking intestinal cholesterol absorption might reduce the progression of fatty liver disease but this needs to be investigated in prospective studies.
“Subgroup analyses showed that the significant associations of protein, carbohydrate and cholesterol intake with cirrhosis or liver cancer that we described in the entire study population, were limited to overweight or obese persons,” the authors report. “No such associations were observed in normal-weight persons.” This suggests that the relevant dietary factors are more likely to have hepatic effects through obesity-related fatty liver disease.
“Our study raises the possibility that dietary factors may be important, modifiable, and hitherto unrecognized determinants of liver disease progression,” the authors conclude.
Diets high in protein and cholesterol are associated with a higher risk of hospitalization or death due to cirrhosis or liver cancer, while diets high in carbohydrates are associated with a lower risk. These findings are in the July issue of Hepatology, a journal published by John Wiley & Sons on behalf of the American Association for the Study of Liver Diseases (AASLD). The article is also available online at Wiley Interscience (www.interscience.wiley.com).
There are many reasons to suspect that dietary factors influence the development of hepatic steatosis and its progression to more severe liver disease. First, poor diet may lead to obesity, insulin resistance and diabetes, which are the most important known risk factors for hepatic steatosis. Also, dietary lipids may directly affect fat in the liver. Furthermore, a high cholesterol diet has been shown to induce serious steatosis in animal studies.
Researchers, led by George Ioannou of Veterans Affairs Puget Sound Health Care System in Seattle, investigated whether dietary nutrient composition was associated with the subsequent development of cirrhosis or liver cancer in a representative sample of the U.S. population. They utilized data from 9,221 participants in the National Health Examination Survey who had completed a 24-hour dietary recall questionnaire. Participants were excluded if they suffered from cirrhosis or liver cancer at the start of the study, or received a diagnosis within five years.
During the follow-up period, an average of 13.3 years, 123 participants received a new diagnosis of cirrhosis (118 people) or liver cancer (5 people) according to hospitalization records and death certificates. These individuals were more likely to be older, more obese with more central fat distribution. They had lower educational attainment and higher alcohol consumption, and were more likely to be male, diabetic and non-white.
Dietary nutrient composition was a strong predictor of hospitalization or death due to cirrhosis or liver cancer in the U.S. population. “In particular, we identified that protein and cholesterol consumption were associated with elevated risk, whereas consumption of carbohydrates was associated with reduced risk of hospitalization or death related to cirrhosis or liver cancer,” the authors report.
The association with cholesterol intake is potentially the most important finding of this study, the authors suggest. While cholesterol is well-known for its role in non-hepatic diseases like atherosclerosis, it has never before been linked to human liver disease. The findings suggest that drugs blocking intestinal cholesterol absorption might reduce the progression of fatty liver disease but this needs to be investigated in prospective studies.
“Subgroup analyses showed that the significant associations of protein, carbohydrate and cholesterol intake with cirrhosis or liver cancer that we described in the entire study population, were limited to overweight or obese persons,” the authors report. “No such associations were observed in normal-weight persons.” This suggests that the relevant dietary factors are more likely to have hepatic effects through obesity-related fatty liver disease.
“Our study raises the possibility that dietary factors may be important, modifiable, and hitherto unrecognized determinants of liver disease progression,” the authors conclude.
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