Friday, September 30, 2011

Resveratrol stops breast cancer growth


New research in the FASEB Journal shows that resveratrol blocks the growth effects of estrogen by reducing the specific breast cancer receptors


A new research report appearing in the October 2011 issue of The FASEB Journal (https://www.fasebj.org) shows that resveratrol, the "healthy" ingredient in red wine, stops breast cancer cells from growing by blocking the growth effects of estrogen. This discovery, made by a team of American and Italian scientists, suggests for the first time that resveratrol is able to counteract the malignant progression since it inhibits the proliferation of hormone resistant breast cancer cells. This has important implications for the treatment of women with breast cancer whose tumors eventually develop resistance to hormonal therapy.

"Resveratrol is a potential pharmacological tool to be exploited when breast cancer become resistant to the hormonal therapy," said Sebastiano Andò, a researcher involved in the work from the Faculty of Pharmacy at the University of Calabria in Italy.

To make this discovery, Andò and colleagues used several breast cancer cell lines expressing the estrogen receptor to test the effects of resveratrol. Researchers then treated the different cells with resveratrol and compared their growth with cells left untreated. They found an important reduction in cell growth in cells treated by resveratrol, while no changes were seen in untreated cells. Additional experiments revealed that this effect was related to a drastic reduction of estrogen receptor levels caused by resveratrol itself.

"These findings are exciting, but in no way does it mean that should people go out and start using red wine or resveratrol supplements as a treatment for breast cancer," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "What it does mean, however, is that scientists haven't finished distilling the secrets of good health that have been hidden in natural products such as red wine."

Wednesday, September 28, 2011

Even high-but-normal blood pressure elevates stroke risk

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People with prehypertension have a 55 percent higher risk of experiencing a future stroke than people without prehypertension, report researchers at the University of California, San Diego School of Medicine in a new meta-analysis of scientific literature published in the September 28 online issue of the journal Neurology.

Prehypertension is clinical category created by experts in 2003 to describe patients whose blood pressure was elevated, but still considered within normal range. Hypertension or abnormally high blood pressure is a major risk factor for cardiovascular disease and strokes, but much less is known about the health threat posed of prehypertension, which is defined by a systolic pressure reading between 120 and 139 mmHg (the top number) and a diastolic reading between 80 and 89 mm Hg (the bottom number)

"The experts reasoned that, generally speaking, the higher the blood pressure, the greater the risk of death and disease, possibly starting from within the normal blood range," said Bruce Ovbiagele, MD, professor of neurosciences at UC San Diego School of Medicine and senior author of the study.

However, Ovbiagele said, conclusive evidence was lacking, "so we decided to compile all the published studies in the scientific literature to date, and using statistical techniques find out if there is indeed a higher risk of future stroke in people with prehypertension, the extent of that risk, and whether particular characteristics were associated with higher stroke risk."

The researchers identified 12 relevant prospective cohort studies of prehypertension. All of the studies were derived from the general population. Four were from the United States, five from Japan, two from China and one from India. Combined, the studies involved more than 518,000 participants and covered periods ranging from 2.7 years to 32 years, with stroke occurrences documented. The prevalence of prehypertension in the studies ranged from 25 to 46 percent. In the United States, it's estimated roughly one-third of adults have prehypertension.

"Overall, people who had prehypertension (in the studies) were at a 55 percent higher risk of experiencing a future stroke than people without prehypertension," said Ovbiagele. "This result held regardless of sex, race-ethnicity, blood pressure type (systolic or diastolic) or the type of stroke (ischemic or hemorrhagic)."

The health risk was measurably greater for those whose blood pressure levels were at the high end of the "normal" spectrum. "We found that those people who fell within the higher range of prehypertension were at 79 percent higher risk of experiencing a future stroke," Ovbiagele said.

The findings should add clarity to the perceived health risk of prehypertension, said Ovbiagele. "Prehypertension has been controversial since its inception, with occasional accusations that it would not be used to diagnose sick people, but rather it would label healthy people whose blood pressure was towards the upper reaches of normal as unhealthy, without any compelling reason for doing so. Others complained that the new designation would needlessly expose people to blood pressure-reduction drugs, all to the benefit of pharmaceutical companies."

Thomas Hemmen, MD, PhD, director of the UC San Diego Stroke Program and a neurologist at the UC San Diego Sulpizio Cardiovascular Center who was not involved in the study, described it as "ground-breaking."

"Over the years, the blood pressure range identified as increasing stroke and cardiovascular risk has been lowered," Hemmen said. "Now anything that's above 115 is thought to increase risk. But we need more tools for diagnosing prehypertension. We need to learn more so that we can adjust risk and develop therapies. Hopefully, this study will lead to more research."

Both Hemmen and Ovbiagele note little empirical evidence exists to show that taking blood pressure-reducing drugs can prevent future strokes. "There just haven't been any large studies," Hemmen said. On the other hand, both doctors say the new findings should encourage persons with high-but-normal blood pressure to change unhealthy behaviors.

"Young and middle-aged persons should check their blood pressure regularly. If they do fall into the higher range of prehypertension, they should take specific steps to modify their lifestyle, such as reducing salt intake and maintaining a normal weight," said Ovbiagele. "Modifying one's lifestyle is relatively safe and could potentially lower not just the risk of future strokes, but possibly other complications of prolonged elevation of blood pressure, including heart attacks, heart failure and kidney disease."

Saw palmetto no more effective than placebo for urinary symptoms

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NIH-funded study finds dietary supplement does not alleviate BPH

Saw palmetto, a widely used herbal dietary supplement, does not reduce urinary problems associated with prostate enlargement any better than a placebo, according to research funded by the National Institutes of Health. The study was published Sept. 28 in the Journal of the American Medical Association.

Prostate enlargement, also called benign prostatic hyperplasia (BPH), can cause frequent urination, a weak or intermittent urine stream and an inability to empty the bladder completely. More than half of men in their 60s, and up to 90 percent in their 70s and 80s, have symptoms of BPH.

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), the National Center for Complementary and Alternative Medicine (NCCAM) and the Office of Dietary Supplements (ODS) supported the study. All are part of the NIH.

According to Robert A. Star, M.D., director of the NIDDK's Division of Kidney, Urologic and Hematologic Diseases, the current study met an important need for rigorous evaluation of standard and higher doses of saw palmetto. The trial also confirmed results of the earlier NIDDK- and NCCAM-sponsored Saw Palmetto Trial for Enlarged Prostates (STEP), which found that a standard daily dose of 320 milligrams provided no greater symptom relief than placebo.

"Investigators designed the current trial to determine whether daily doses of up to 960 milligrams — three times the standard daily dose — would prove better than a placebo at improving lower urinary tract symptoms in men due to BPH," said Star. "We were disappointed to find that higher doses of saw palmetto did not improve symptoms more than placebo."

Josephine P. Briggs, M.D., director of NCCAM, added that this study further illustrates the importance of conducting research on botanical products that are used extensively by the general public.

"This was a well-designed study that addressed limitations of earlier, smaller trials — it was a multicenter study with a larger sample size and tested different doses of a carefully analyzed saw palmetto product," Briggs said. "The NIH is committed to bringing rigorous science to the study of natural products and to building the evidence base that can guide consumer decisions."

The study was a double-blind randomized placebo-controlled clinical trial conducted at 11 North American clinical sites from June 2008 to October 2010. A cohort of 369 men aged 45 years or older participated, each with a peak urine flow rate of at least four milliliters per second at the beginning of the study — which is less than normal. Also, all had an American Urological Association Symptom Index (AUASI) score of between eight and 24 — a lower score is better. The AUASI score ranges from zero to 35. Escalating doses of saw palmetto or placebo were given, starting at one, then two, and then three pills of 320 milligrams per day, with dose increases at 24 and 48 weeks.

The study measured the differences between the AUASI score at the start of the trial and after 72 weeks of treatment. Secondary measures included improvements in frequency, nocturia (nighttime urination), peak urine flow, prostate-specific antigen (PSA) level, sexual function, incontinence and sleep quality.

Between baseline and 72 weeks, mean AUASI scores decreased from 14.4 to 12.2 points with saw palmetto extract and from 14.7 to 11.7 points with placebo. The group average change in AUASI score from baseline to 72 weeks between the saw palmetto and placebo groups was 0.79 points, favoring placebo. Saw palmetto was not more effective than placebo in reducing urinary symptoms for any of the secondary outcomes.

According to Joseph M. Betz, Ph.D., director of the Analytical Methods and Reference Materials program at ODS and a study co-author, the study used a very well-characterized saw palmetto product. Through batch testing, study investigators took extreme care to ensure that the composition of the supplement was consistent over the whole study.

"Saw palmetto and other herbs are often manufactured in different ways, so no two brands are likely to have the same composition," Betz said.

Tuesday, September 27, 2011

Low Vitamin B12 Levels May Lead to Brain Shrinkage, Cognitive Problems

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Older people with low levels of vitamin B12 in their blood may be more likely to lose brain cells and develop problems with their thinking skills, according to a study published in the September 27, 2011, print issue of Neurology®, the medical journal of the American Academy of Neurology. Foods that come from animals, including fish, meat, especially liver, milk, eggs and poultry, are usually sources of vitamin B12.

The study involved 121 people age 65 and older living on the south side of Chicago. Their blood was drawn to measure levels of vitamin B12 and B12-related metabolites that can indicate a B12 deficiency. The participants also took tests measuring their memory and other cognitive skills. An average of four-and-a-half years later, MRI scans of the participants’ brains were taken to measure total brain volume and look for other signs of brain damage.

Having high levels of four of five markers for vitamin B12 deficiency was associated with having lower scores on the cognitive tests and smaller total brain volume.
“Our findings definitely deserve further examination,” said study author Christine C. Tangney, PhD, of Rush University Medical Center in Chicago. “It’s too early to say whether increasing vitamin B12 levels in older people through diet or supplements could prevent these problems, but it is an interesting question to explore. Findings from a British trial with B vitamin supplementation are also supportive of these outcomes.”

On the cognitive tests, the scores ranged from -2.18 to 1.42, with an average of 0.23. For each increase of one micromole per liter of homocysteine—one of the markers of B12—the cognitive scores decreased by 0.03 standardized units or points.
Tangney noted that the level of vitamin B12 itself in the blood was not associated with cognitive problems or loss in brain volume. She said that low vitamin B12 can be difficult to detect in older people when looking only at blood levels of the vitamin

Increased Caffeinated Coffee Consumption Associated With Decreased Risk of Depression in Women

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The risk of depression appears to decrease for women with increasing consumption of caffeinated coffee, according to a report in the September 26 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

Caffeine is the most frequently used central nervous system stimulant in the world, and approximately 80 percent of consumption is in the form of coffee, according to background information in the article. Previous research, including one prospective study among men, has suggested an association between coffee consumption and depression risk. Because depression is a chronic and recurrent condition that affects twice as many women as men, including approximately one of every five U.S. women during their lifetime, “identification of risk factors for depression among women and the development of new preventive strategies are, therefore, a public health priority,” write the authors. They sought to examine whether, in women, consumption of caffeine or certain caffeinated beverages is associated with the risk of depression.

Michel Lucas, Ph.D., R.D., from the Harvard School of Public Health, Boston, and colleagues studied 50,739 U.S. women who participated in the Nurses’ Health Study. Participants, who had a mean (average) age of 63, had no depression at the start of the study in 1996 and were prospectively followed up with through June 2006. Researchers measured caffeine consumption through questionnaires completed from May 1980 through April 2004, including the frequency that caffeinated and noncaffeinated coffee, nonherbal tea, caffeinated soft drinks (sugared or low-calorie colas), caffeine-free soft drinks (sugared or low-calorie caffeine-free colas or other carbonated beverages) and chocolate were usually consumed in the previous 12 months. The authors defined depression as reporting a new diagnosis of clinical depression and beginning regular use of antidepressants in the previous two years.

Analysis of the cumulative mean consumption included a two-year latency period; for example, data on caffeine consumption from 1980 through 1994 were used to predict episodes of clinical depression from 1996 through 1998; consumption from 1980 through 1998 were used for the 1998 through 2000 follow-up period; and so on. During the 10-year follow-up period from 1996 to 2006, researchers identified 2,607 incident (new-onset) cases of depression. When compared with women who consumed one cup of caffeinated coffee or less per week, those who consumed two to three cups per day had a 15 percent decrease in relative risk for depression, and those consuming four cups or more per day had a 20 percent decrease in relative risk. Compared with women in the lowest (less than 100 milligrams [mg] per day) categories of caffeine consumption, those in the highest category (550 mg per day or more) had a 20 percent decrease in relative risk of depression. No association was found between intake of decaffeinated coffee and depression risk.

“In this large prospective cohort of older women free of clinical depression or severe depressive symptoms at baseline, risk of depression decreased in a dose-dependent manner with increasing consumption of caffeinated coffee,” write the authors. They note that this observational study “cannot prove that caffeine or caffeinated coffee reduces the risk of depression but only suggests the possibility of such a protective effect.” The authors call for further investigations to confirm their results and to determine whether usual caffeinated coffee consumption could contribute to prevention or treatment of depre

Research Finds Link Between Statin Use and Progressive Muscle Disease

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Each year, millions of Americans take statins, drugs collectively known to lower their blood cholesterol levels. While the drugs have proven effective in reducing heart attacks and strokes, for some people these benefits come at a cost: widespread muscle pain that persists as long as the drugs are taken. New NIAMS-supported research has found that for a subset of patients, statins appear to trigger a far more serious muscle condition that persists long after the drugs are stopped.

This discovery, published in the journal Arthritis & Rheumatism by a multidisciplinary team of researchers at The Johns Hopkins University, began in 2010 when they noted that some patients at the university’s Myositis Center had unique antibodies that seemed to be associated with necrotizing myopathy, a progressive muscle wasting disease of unknown cause. Further investigation revealed that as many as three-fourths of these patients had previously used statins, leading the researchers to suspect from prior related research, that the condition might be an autoimmune disease associated with statins. In other words, they suspected statins might have somehow triggered these people’s immune systems to produce antibodies against components of their own bodies.

Following this hunch, the researchers set out to find the cause of the suspected autoimmune response. A series of "smart guesses" led them to 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), an enzyme in the body involved in the production of cholesterol, says Lisa Christopher-Stine, M.D., co-director of the Johns Hopkins Myositis Center and one of the NIAMS-funded researchers involved in the discovery. In the patients with necrotizing myopathy, the researchers found that autoantibodies (so-called because they react to the body’s own molecules) attack the body’s natural HMGCR. While statins work by inhibiting the body’s natural HMGCR, the body churns out more of the enzyme in an effort to compensate for the reduction caused by the statin. In a small percentage of people, they suspect, this extra HMGCR is the target of the immune system’s attack.

Making the problem worse was an earlier finding in 2005 by Livia Casciola-Rosen, Ph.D., and colleagues at Johns Hopkins that implicates regenerating muscle cells rather than mature muscle cells as the source of ongoing HMGCR supply in people with statin-induced myopathy. This suggests that, once the immune system starts to attack HMGCR and muscle damage begins, the regeneration to replace damaged muscle only fuels the problem — even when statins are stopped — says Dr. Christopher-Stine.

Unlike more common muscle pain from statins, this condition requires the use of corticosteroids and other drugs to suppress the immune system, with the goal of stopping progressive muscle damage, says Dr. Christopher-Stine. But even in these cases, she warns that stopping the statin — and forgoing its benefits to the cardiovascular system — may not be necessary. Treating with a statin and immunosuppressive drugs simultaneously may be preferable in some cases.

Eventually, the researchers believe their work could lead to tests that would enable doctors to identify which statin users have muscle pain that will improve on its own, and which ones require treatment to slow or stop progressive muscle disease. In the meantime, they urge doctors and patients not to avoid statins, which are among the most useful and commonly prescribed drugs. For patients who take statins and experience muscle pain, they recommend that doctors look for signs that could indicate a more severe problem such as difficulty swallowing, reduced grip strength, blood tests showing persistently elevated muscle enzymes and/or muscle pain that persists longer than 12 weeks despite statin cessation.

The mission of the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), a part of the U.S. Department of Health and Human Services' National Institutes of Health, is to support research into the causes, treatment and prevention of arthritis and musculoskeletal and skin diseases; the training of basic and clinical scientists to carry out this research; and the dissemination of information on research progress in these diseases. For more information about NIAMS, call the information clearinghouse at (301) 495-4484 or (877) 22-NIAMS (free call) or visit the NIAMS website at http://www.niams.nih.gov.

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Casciola-Rosen L, Nagaraju K, Plotz P, Wang K, Levine S, Gabrielson E, Corse A, Rosen A. Enhanced autoantigen expression in regenerating muscle cells in idiopathic inflammatory myopathy. J Exp Med. 2005 Feb 21; 201(4):591-601.

Christopher-Stine L, Casciola-Rosen LA, Hong G, Chung T, Corse AM, Mammen AL. A novel autoantibody recognizing 200-kd and 100-kd proteins is associated with an immune-mediated necrotizing myopathy. Arthritis Rheum. 2010 Sep; 62(9):2757-66.

Mammen AL, Chung T, Christopher-Stine L, Rosen P, Rosen A, Doering KR, Casciola-Rosen LA. Autoantibodies against 3-hydroxy-3-methylglutaryl-coenzyme A reductase in patients with statin-associated autoimmune myopathy. Arthritis Rheum. 2011 Mar; 63(3):713-21.

Monounsaturated Fatty Acids = Less Cognitive Decline

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A diet high in monounsaturated fatty acids may be associated with less cognitive decline in older healthy women, according to a study published in the Journal of the American Geriatrics Society. Previous research has linked cognitive decline with cardiovascular disease, and certain types of dietary fatty acids (saturated and trans) are a known risk factor for cardiovascular disease. However, in this study, no association was found between cognitive decline and saturated or trans fatty acids. Monounsaturated fats are found in olive and canola oils, and saturated fats are found in coconut and palm oils as well as in butter, cheese, milk, and fatty meats. Trans fats are found in some margarines, commercial baked goods, and other foods made with or fried in partially hydrogenated oil.

Researchers analyzed the dietary intake of 482 women aged 60 and older from a food frequency questionnaire, and assessed their cognitive function—memory, vision, executive function, language, and attention—upon enrollment and again after 3 years. The study is part of a larger observational study that examined associations between dietary and lifestyle factors and cognitive function in older women without dementia.

The researchers found that a higher intake of dietary monounsaturated fatty acids was associated with less cognitive decline over a 3-year period. Further, after testing for associations between monounsaturated fatty acids and individual components of cognitive function, the researchers found that greater intake of monounsaturated fatty acids was associated with less decline in visual-spatial ability and memory after adjusting for other factors (i.e., age, education, reading ability). In addition, higher intakes of saturated fatty acids, trans-fatty acids, and dietary cholesterol were not associated with cognitive decline after adjusting for other factors.

The researchers noted that monounsaturated fatty acids have anti-inflammatory effects and suggested that these effects may provide one explanation for their protection against cognitive decline (as chronic inflammation appears to be one contributor to Alzheimer’s disease). Limitations of this observational analysis include the small sample size and the use of a study population consisting primarily of healthy, educated Caucasian women, which the researchers noted may limit the generalizability of findings to other populations.

See also: Fish oil's positive impact on cognition and brain structure

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High Blood Pressure Is Linked to Increased Risk of Developing or Dying from Cancer

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Raised blood pressure is linked to a higher risk of developing cancer or dying from the disease according to the findings of the largest study to date to investigate the association between the two conditions.

Dr Mieke Van Hemelrijck will tell the 2011 European Multidisciplinary Cancer Congress in Stockholm that there had been contradictory results from previous, smaller studies investigating the link between cancer and blood pressure. However, her study, which included 289,454 men and 288,345 women, showed that higher than normal blood pressure was statistically significantly associated with a 10-20% higher risk of developing cancer in men, and a higher risk of dying from the disease in both men and women.

Dr Van Hemelrijck, a research associate in the Cancer Epidemiology Group at King's College London (London, UK), and her colleagues analysed data on blood pressure and cancer incidence and death in a prospective study that included seven groups of participants in Norway, Austria and Sweden.

They used figures on mid-blood pressure for their calculations. Mid-blood pressure is defined as systolic blood pressure plus diastolic blood pressure, divided by two. The average mid-blood pressure in this study was 107 mmHg for men and 102 mmHG for women. The results were divided into five groups (or quintiles), so that people with the lowest mid-blood pressure were in the first, and those with the highest mid-blood pressure were in the fifth quintile.

After an average of 12 years of follow-up and excluding the first year, 22,184 men and 14,744 women had been diagnosed with cancer, and 8,724 men and 4,525 women died from the disease. The overall risk of developing any cancer increased by 29% between men in the lowest quintile and those in the highest. The researchers also found that, as blood pressure rose, the risk of oral, colorectal, lung, bladder, and kidney cancers, melanoma and non-melanoma skin cancers rose in men. In women, increased blood pressure was not statistically significantly associated with the overall risk of developing any cancer, but was associated with an increased risk of cancers of the liver, pancreas, cervix and endometrium and melanoma.

In both men and women, there was an increased risk of dying from cancer; men in the fifth quintile had a 49% increased risk of dying compared to those in the first quintile, and women in the fifth quintile had a 24% increased risk compared to those in the first.

Dr Van Hemelrijck explained: "This means that we found that men with mid-blood pressure in the highest fifth had an absolute risk of developing cancer of 16% compared to an absolute risk of 13% for those with mid-blood pressure in the lowest fifth. Men in the highest fifth had an absolute risk of dying from cancer of eight percent, compared to an absolute risk of five percent for those in the lowest; and for women, those in the highest fifth had an absolute risk of dying of five percent compared to an absolute risk of four percent in the lowest fifth.

"Our study shows that blood pressure is a risk factor for incident cancer in men and fatal cancer in men and women. Although the relative and absolute risk estimates were rather modest, these results are important from a public health perspective since a large proportion of the population in many western countries suffers from hypertension."

The researchers adjusted their results to take account of age, sex, body mass index, smoking and random errors in the exposure classification of blood pressure (errors that occur due to inaccuracy in blood pressure measurements or due to an individual patient's variations in blood pressure, which can be corrected by using data from several examinations).

Dr Van Hemelrijck warned that, as the study was observational, it could not show that blood pressure was the cause of the increased cancer risk. "We cannot claim that there is a causal link between high blood pressure and cancer risk, nor can we say that the cause of cancer is a factor related with high blood pressure," she said. "However a healthy lifestyle, including sufficient physical activity and a normal weight, has been shown to reduce the risk of several chronic diseases. For instance, high blood pressure is a known risk factor for cardiovascular disease, and our study now indicates that high blood pressure may also be a risk factor for cancer."

The researchers are unsure why men with high blood pressure appeared to have a higher cancer risk than women. "Our study, which to our knowledge is the largest and the first to take into account random error, showed that the association between hypertension and incident or fatal cancer is stronger for men than for women. In contrast, the second largest study previously found a higher cancer risk for women than for men. The differences in findings might be explained due to our larger sample size, slightly older population, adjustment for random error, or lack of information on anti-hypertensive treatment," she said.

The Metabolic syndrome and Cancer project (Me-Can) was set up in 2006 to investigate the relationship between various metabolic conditions and the risk of cancer using data from health examinations carried out on patients between 1972-2005. Two of its initiators, Dr Tanja Stocks and Professor Pär Stattin at Umeå University, Sweden, analysed these data on blood pressure and cancer together with Dr Van Hemelrijck.

ECCO spokesperson, Professor Jan Willem Coebergh, from the Eindhoven Cancer Registry (The Netherlands), said: "This extensive, population-based study of the role of concomitant hypertension shows that it has a modest effect on the risk of certain cancers, especially of the kidney and colorectum, but it is probably a smaller effect than that caused by diabetes and various vascular conditions."

ESMO spokesperson, Dr Franco Berrino, from the Istituto Nazionale Tumori in Milan, Italy, said: "There is increasing evidence that metabolic syndrome is associated with a higher risk of developing cancer as well as other chronic diseases. As an unhealthy lifestyle is a major determinant of hypertension, these results from the highly productive MeCan project add to the evidence that lifestyles affect both the risk and prognosis of cancer."

Monday, September 26, 2011

Exposure to goats could increase the risk of lung cancer

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Exposure to goats could increase the risk of a certain type of lung cancer, according to French researchers.

The study has linked a professional exposure to goats with a distinct subset of lung cancer, known as pneumonic-type lung adenocarcinoma (P-ADC).

This form of lung cancer has a weak association with tobacco smoking when compared with other types of the disease. In attempting to identify other triggers that may cause the disease, scientists have previously noticed similarities between P-ADC and a viral infection which causes growths in the lungs of sheep. Given these similarities, the researchers have investigated whether a viral agent found in sheep and goats could be easily transferred to people who work with the animals, leading to a partiality for P-ADC.

The current epidemiologic study involved 44 patients with P-ADC and 132 controls without the disease. All participants were given a questionnaire assessing a number of risk factors including their smoking status, their personal history of cancer and their exposure to goats.

The results showed that people who had experienced a professional exposure to goats during their lifetime were five times more likely to get P-ADC compared with other types of lung cancer.

The findings also showed that P-ADC was significantly associated with females, and people who had never smoked or had any personal history of cancer.

Dr Nicolas Girard, from the Louis Pradel Hospital, Hospices Civils de Lyon, said: "Scientists have noticed similarities between P-ADC and a contagious viral infection in sheep before. This led us to explore the possibility that professional exposure to cattle could make humans more susceptible to P-ADC. These findings demonstrate that exposure to goats could be a risk factor for this type of lung cancer, however further studies are needed to assess other potential risk factors for the disease."

Alcohol can reduce asthma risk

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Amsterdam, The Netherlands: Drinking alcohol in moderate quantities can reduce the risk of asthma, according to Danish researchers.

The study, which will be presented today (25 September 2011) at the European Respiratory Society's Annual Congress in Amsterdam, found that drinking 1-6 units of alcohol a week could reduce the risk of developing the condition.

The research examined 19,349 twins between the ages of 12 and 41 yrs of age. All participants completed a questionnaire at the start and end of the study to compare alcohol intake with the risk of developing asthma over 8 yrs.

The results showed that the lowest risk of asthma was seen in the group which had a moderate intake of alcohol, as less than 4% of those who drank 1-6 units per week developed asthma.

The highest risk of asthma was observed in people who drunk rarely or never, as they were 1.4-times more likely to develop the condition. Heavy drinkers also had an increased risk of asthma development and were 1.2-times more likely to develop asthma.

The results also suggested that a preference for beer drinking was associated with an increased risk of asthma when compared with no preference.

Previous studies have found a link between excessive intake of alcohol and asthma attacks; however, this is the first study of its kind to show a link between alcohol intake and the onset of asthma for adults over a long period of time.

Sofie Lieberoth, from the Bispebjerg Hospital in Denmark, said: "Whilst excessive alcohol intake can cause health problems, the findings of our study suggest that a moderate intake of 1-6 units can reduce the risk of developing asthma. By examining all the factors linked with the development of asthma, we can understand more about what causes the condition and how to prevent it."

Fruits and vegetables reduce risks of specific types of colorectal cancers

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The effects of fruit and vegetable consumption on colorectal cancer (CRC) appear to differ by site of origin, according to a new study published in the October issue of the Journal of the American Dietetic Association. Researchers found that within the proximal and distal colon, brassica vegetables (Brussels sprouts, cabbage, cauliflower and broccoli) were associated with decreased risk of these cancers. A lower risk of distal colon cancer was associated with eating more apples, however an increased risk for rectal cancer was found with increasing consumption of fruit juice.

"Fruits and vegetables have been examined extensively in nutritional research in relation to CRC, however, their protective effect has been subject to debate, possibly because of different effects on different subsites of the large bowel," commented lead investigator Professor Lin Fritschi, PhD, head of the Epidemiology Group at the Western Australian Institute for Medical Research, Perth, Western Australia. "It may be that some of the confusion about the relationship between diet and cancer risk is due to the fact that previous studies did not take site of the CRC into account. The replication of these findings in large prospective studies may help determine whether a higher intake of vegetables is a means for reducing the risk of distal CRC."

Researchers from the Western Australian Institute for Medical Research, University of Western Australia and Deakin University investigated the link between fruit and vegetables and three cancers in different parts of the bowel: proximal colon cancer, distal colon cancer, and rectal cancer. The case-control study included 918 participants with a confirmed CRC diagnosis and 1021 control participants with no history of CRC. The subjects completed extensive medical and nutritional questionnaires and were assigned a socioeconomic status based on their home address.

Consumption of brassica vegetables (e.g., broccoli, cabbage) was associated with reduced incidence of proximal colon cancer. For distal colon cancer, both total fruit and vegetable intake and total vegetable intake appeared to decrease risk. Distal colon cancer risk was significantly decreased in association with intake of dark yellow vegetables and apples, although there was an increased risk for rectal cancer with consumption of fruit juice. Risk of proximal colon cancer and rectal cancer was not associated with intakes of total fruit and vegetable, total vegetable or total fruit.

Previous studies on CRC have often failed to distinguish between the different sites of origin of cancers in the large bowel, even though it is now well established that tumors in the proximal colon develop along different pathways to those of the distal colon and rectum and that risk of cancer varies by subsite within the colorectum. The mechanisms for different effects of dietary components on different sites of the large bowel have not yet been determined.

The authors conclude that "from a public health point of view it is easier to translate food-based analyses into dietary recommendations, rather than using the intake of single nutrient."

Friday, September 23, 2011

Moving Despite Back Pain Better Than Resting


Patients Who Followed Recommendations to Move Despite Back Pain Fared Better Than Those That Rested in Small Study


A researcher at the Sahlgrenska Academy, University of Gothenburg suggests that people with back pain who are advised to stay active should move despite the pain, not rest. Patients with acute low back pain who were advised to stay active despite the pain fared better than those who were told to adjust their activity in line with their pain.

The thesis looked at 109 patients with acute severe lowback pain. They were randomly advised in one of two ways: "stay active even though it hurts" or "adjust your activity to the pain." They were also asked to keep a diary for seven days and to note how many steps they took each day, to what extent they could carry out their day-to-day activities and how they felt physically. They also completed a form to show whether they felt depressed or not.

In spite of having more pain, the group that was advised to be as active as possible recovered more quickly and did not feel depressed at the end of the follow-up.

"The other category, who had been advised from the very start to adjust their activity to their pain, were less mobile and felt slightly depressed compared to the patients who were active," says Olaya-Contreras, a researcher at the Sahlgrenska Academy's Department of Orthopaedics.

She believes that this could be because some people who are depressed and in pain experience the pain more acutely. Another explanation could be that the more acute the pain is perceived to be, the less a person wants or is able to move. This, according to Olaya-Contreras, is in line with previous research.

"I think that if you're suffering with acute low back pain you should try to remain as active as possible and go about your daily business as well as you can. If you don't keep moving, it's easy to get locked into a downward spiral, as inactivity combined with pain can, in a worst case scenario, turn into long-term disability and an inability to work that, in turn, can lead to depressed mood and more pain."

Olaya-Contreras therefore feels that the health service should introduce a routine investigation to determine the underlying psycho-social causes of patients' back problems. This could measure the degree of perceived depression as well as anxiety and fear of movement.

"The results of the investigation and associated discussion could lead to patients taking a more active role and taking responsibility for their treatment," says Olaya-Contreras. "I also believe that it can help patients to focus more on the positive resources they themselves have to handle the pain and master various physical movements even though it hurts."

Back Problems

Low back pain affects up to 80% of people of working age at some time in their lives, though most will get better. Low back pain can be recurring, and some people will continue to suffer with some degree of pain. In 85-90% of cases the pain cannot be attributed to a specific illness or injury.

Depression Associated With Increased Risk of Stroke and Stroke-Related Death

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An analysis of nearly 30 studies including more than 300,000 patients finds that depression is associated with a significantly increased risk of developing stroke and dying from stroke, according to an article in the September 21 issue of JAMA.

"Stroke is a leading cause of death and permanent disability, with significant economic losses due to functional impairments. Depression is highly prevalent in the general population, and it is estimated that 5.8 percent of men and 9.5 percent of women will experience a depressive episode in a 12-month period. The lifetime incidence of depression has been estimated at more than 16 percent in the general population," according to background information in the article. Whether depression increases the risk of stroke has been unclear.

An Pan, Ph.D., of the Harvard School of Public Health, Boston, and colleagues conducted a systematic review and a meta-analysis of prospective cohort studies to describe the association between depression and risk of total and subtypes of stroke. The researchers conducted a search of the medical literature and identified 28 prospective cohort studies that met criteria for inclusion in the analysis. The studies, which included 317,540 participants, reported 8,478 stroke cases during a follow-up period ranging from 2 to 29 years.

The researchers found that when the data from the studies were pooled, analysis indicated that depression was associated with a 45 percent increased risk for total stroke; a 55 percent increased risk for fatal stroke; and a 25 percent increased risk for ischemic stroke. Depression was not associated with an increased of hemorrhagic stroke.

The corresponding absolute risk difference associated with depression based on the most recent stroke statistics for the United States was estimated to be, per 100,000 individuals per year, 106 cases for total stroke, 53 cases for ischemic stroke, and 22 cases for fatal stroke.

The researchers speculate that depression may contribute to stroke through a variety of mechanisms, including having known neuroendocrine (relating to the nervous and endocrine systems) and immunological/inflammation effects; poor health behaviors (i.e., smoking, physical inactivity, poor diet, lack of medication compliance) and obesity; having other major comorbidities, such as diabetes and hypertension, both of which are major risk factors for stroke; and antidepressant medication use, which may contribute to the observed association.

"In conclusion, this meta-analysis provides strong evidence that depression is a significant risk factor for stroke. Given the high prevalence and incidence of depression and stroke in the general population, the observed association between depression and stroke has clinical and public health importance. More studies are needed to explore the underlying mechanisms and elucidate the causal pathways that link depression and stroke."

Thursday, September 22, 2011

Soy protein reduced progression of clogged arteries in women within 5 years of menopause

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This large scale, first-of-a-kind study will be published in the November issue of Stroke

A new study published in the November 2011 issue of Stroke reveals some promising data on the positive effects of soy protein reducing the progression of clogged arteries in women who were within five years of menopause. This study was the largest and longest randomized controlled human study conducted to-date that directly investigated the efficacy of isolated soy protein consumption on the progression of atherosclerosis (lipid deposition in the artery walls).

"These results are consistent with what we have learned through research conducted over the past decade," said Howard N. Hodis, MD, USC Keck School of Medicine and lead author of the study. "The literature demonstrates that there is a 'window of opportunity' of a potential beneficial effect on coronary heart disease for products that bind to the estrogen receptor including hormone-replacement therapy, soybean isoflavones or selective estrogen receptor modulators (SERMs) when initiated in women within 5-6 years of menopause."

The progression rate of carotid artery intima-media thickness (CIMT) trended to be 16 percent lower on average in the isoflavone-containing soy protein group compared with the placebo group. However, in women who had experienced menopause within the past five years, isolated soy protein consumption was associated with a significant 68 percent reduction in CIMT progression compared to those consuming the placebo.

Excellent compliance was observed for this study as determined by package and bar count (86.5 percent for placebo and 91.0 percent for isolated soy protein). Compliance was confirmed by plasma and urine isoflavone measurements.

"The high compliance suggests that the clinical study products provided by Solae were very palatable and were not associated with any significant adverse effects as confirmed by the data," said Elaine Krul, PhD, nutrition discovery lead, Solae.

Subjects in this study were 'healthy' with no previous signs of cardiovascular disease which may explain the lack of significant reduction in plasma lipids that is seen in persons with higher plasma lipid levels.

"This study also showed a significant increase in HDL ("the good") cholesterol in participants consuming isolated soy protein," said Krul. "The results of this study reinforce that soy protein can provide health benefits for the healthy aging market segment."

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The study was conducted between 2004 and 2009. It was a double-blind, placebo-controlled parallel-design study of 350 postmenopausal women aged 45-92 years without diagnosed diabetes or heart disease that were recruited in Greater Los Angeles.

Monday, September 19, 2011

A Bout of Exercise May be the Cure for Brain Fatigue

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Researchers have long known that regular exercise increases the number of organelles called mitochondria in muscle cells. Since mitochondria are responsible for generating energy, this numerical boost is thought to underlie many of the positive physical effects of exercise, such as increased strength or endurance. Exercise also has a number of positive mental effects, such as relieving depression and improving memory. However, the mechanism behind these mental effects has been unclear. In a new study in mice, researchers at the University of South Carolina have discovered that regular exercise also increases mitochondrial numbers in brain cells, a potential cause for exercise’s beneficial mental effects.

Their article is entitled "Exercise Training Increases Mitochondrial Biogenesis in the Brain." It appears in the Articles in PresS section of the American Journal of Physiology – Regulatory, Integrative, and Comparative Physiology, published by the American Physiological Society.

Methodology

The researchers assigned mice to either an exercise group, which ran on an inclined treadmill six days a week for an hour, or to a sedentary group, which was exposed to the same sounds and handling as the exercise group but remained in their cages during the exercise period. After eight weeks, researchers examined brain and muscle tissue from some of the mice in each group to test for signs of increases in mitochondria. Additionally, some of the mice from each group performed a "run to fatigue" test to assess their endurance after the eight-week period.

Results

Confirming previous studies, the results showed that mice in the exercise group had increased mitochondria in their muscle tissue compared to mice in the sedentary group. However, the researchers also found that the exercising mice also showed several positive markers of mitochondria increase in the brain, including a rise in the expression of genes for proxisome proliferator-activated receptor-g coactivator 1-alpha, silent information regulator T1, and citrate synthase, all regulators for mitochondrial biogenesis; and mitochondrial DNA. These results correlate well with the animals’ increased fitness. Overall, mice in the exercise group increased their run to fatigue times from about 74 minutes to about 126 minutes. No change was seen for the sedentary mice.

Importance of the Findings

These findings suggest that exercise training increases the number of mitochondria in the brain much like it increases mitochondria in muscles. The study authors note that this increase in brain mitochondria may play a role in boosting exercise endurance by making the brain more resistant to fatigue, which can affect physical performance. They also suggest that this boost in brain mitochondria could have clinical implications for mental disorders, making exercise a potential treatment for psychiatric disorders, genetic disorders, and neurodegenerative diseases.

"These findings could lead to the enhancement of athletic performance through reduced mental and physical fatigue, as well as to the expanded use of exercise as a therapeutic option to attenuate the negative effects of aging, and the treatment and/or prevention of neurological diseases," the authors say.

Jon's Health Tips - Latest Health Research

1. I always thought the best part (healthwise) of the apples I eat (and I should eat more) was the skin:

Apples and pears may keep strokes away.

That's the conclusion of a Dutch study published in Stroke: Journal of the American Heart Association in which researchers found that eating a lot of fruits and vegetables with white flesh may protect against stroke.

While previous studies have linked high consumption of fruits and vegetables with lower stroke risk, the researchers' prospective work is the first to examine associations of fruits and vegetable color groups with stroke.

The color of the edible portion of fruits and vegetables reflects the presence of beneficial phytochemicals such as carotenoids and flavonoids.

Fruits and vegetables were classified in four color groups:

* Green, including dark leafy vegetables, cabbages and lettuces
* Orange/Yellow, which were mostly citrus fruits
* Red/Purple, which were mostly red vegetables
* White, of which 55 percent were apples and pears

During 10 years of follow-up, 233 strokes were documented. Green, orange/yellow and red/purple fruits and vegetables weren't related to stroke. However, the risk of stroke incidence was 52 percent lower for people with a high intake of white fruits and vegetables compared to people with a low intake.

Each 25 gram per day increase in white fruits and vegetable consumption was associated with a 9 percent lower risk of stroke. An average apple is 120 grams.

"To prevent stroke, it may be useful to consume considerable amounts of white fruits and vegetables. For example, eating one apple a day is an easy way to increase white fruits and vegetable intake. However, other fruits and vegetable color groups may protect against other chronic diseases. Therefore, it remains of importance to consume a lot of fruits and vegetables."

Apples and pears are high in dietary fiber and a flavonoid called quercetin. In the study, other foods in the white category were bananas, cauliflower, chicory and cucumber.


2. I need to eat more yogurt:

Probiotics Have Slight Preventive Effect on Colds: Review

Taking probiotics seems to provide both children and adults with a mild degree of protection against many upper respiratory tract infections (URTI) including the common cold, according to a new systematic review. People who consume probiotics are also less likely to end up taking antibiotics for an upper respiratory infection, the review found.

Probiotics are in fermented foods like yogurt, soy yogurt and kefir. People also often take probiotics as supplements. The reviewers compared how often colds and other respiratory infections occurred in people who consumed probiotics to people who took placebos and found a statistically significant difference.



3. I'm glad I take a statin for high cholesterol:

a. People with high cholesterol may have a higher risk of developing Alzheimer's disease

b. Statins reduce deaths from infection and respiratory illness

4. I eat a lot of broccoli but it's probably overcooked and I don't put mustard on it as I should:

Spicing up broccoli boosts its cancer-fighting power

Teaming fresh broccoli with a spicy food that contains the enzyme myrosinase significantly enhances each food's individual cancer-fighting power and ensures that absorption takes place in the upper part of the digestive system where you'll get the maximum health benefit, suggests a new University of Illinois study.

"To get this effect, spice up your broccoli with broccoli sprouts, mustard, horseradish, or wasabi. The spicier, the better; that means it's being effective," said Elizabeth Jeffery, a U of I professor of nutrition. It's no secret that many people cook the benefits right out of broccoli instead of steaming it lightly for two to four minutes to protect its healthful properties, she said. "However, this study shows that even if broccoli is overcooked, you can still boost its benefits by pairing it with another food that contains myrosinase," she said.


5. I'll drink to that:

a. Alcohol intake and 'successful aging'
Among 13,894 women in the Nurses' Health Study, investigators prospectively examined alcohol use assessed at midlife in relation to "successful aging," which was defined as survival to age 70 years, not having a major chronic disease (such as coronary disease, cancer, stroke, diabetes), and having no major cognitive impairment, physical impairment, or mental health problems. Only 11% of the women met these criteria.

The results indicate that moderate drinkers, especially those consuming wine and drinking regularly, were more likely to exhibit successful ageing. For average amount consumed, the largest benefit (an increase of 28%) was among women who reported 15.1 – 30 g of alcohol per day (an average of just over 1 to 2 _ drinks per day), when compared with non-drinkers. The frequency of drinking was especially important: in comparison with nondrinkers, women who drank only on 1 to 2 days per week had little increase in their risk of successful aging, but those drinking on at least 5 days per week had almost a 50% greater chance of successful aging.


b. Daily Moderate Drinking Helps Clogged Arteries - Weekend Binge Hurts


In the journal Atherosclerosis, scientists found that daily moderate drinking – the equivalent of two drinks per day, seven days a week – decreased atherosclerosis in mice, while binge drinking – the equivalent of seven drinks a day, two days a week – increased development of the disease. Atherosclerosis, or the hardening and narrowing of arteries, is a serious condition that can lead to a heart attack or stroke.


6. I've always felt that I need regular exercise to keep me from going crazy, but here's proof:

Aerobic Exercise May Reduce the Risk of Dementia

Any exercise that gets the heart pumping may reduce the risk of dementia and slow the condition’s progression once it starts, reported a Mayo Clinic study published this month in Mayo Clinic Proceedings. Researchers examined the role of aerobic exercise in preserving cognitive abilities and concluded that it should not be overlooked as an important therapy against dementia.

The researchers broadly defined exercise as enough aerobic physical activity to raise the heart rate and increase the body’s need for oxygen. Examples include walking, gym workouts and activities at home such as shoveling snow or raking leaves.


7. I've always avoided baked potatoes because of their high glycemic index. But new research is eye-opening as is the article below:

a. Baked Potatoes Reduce Blood Pressure

The potato’s stereotype as a fattening food for health-conscious folks to avoid is getting another revision today as scientists report that just a couple servings of spuds a day reduces blood pressure almost as much as oatmeal without causing weight gain. S

But don’t reach for the catsup, vinegar or mayonnaise. The research was not done with French fries, America’s favorite potato, but with potatoes cooked without oil in a microwave oven. Although researchers used purple potatoes, they believe that red-skin potatoes and white potatoes may have similar effects.


b. The TRUTH about Potatoes, Glycemic Index, and "White Foods" - Friend or Foe for Fat Loss?

White potatoes are actually a healthy carbohydrate as long as you eat them in the right form... with the entire skin, and please don't ruin them by deep frying them into french fries either! French fries are one of the most evil things ever invented for your health, but only because we ruin them by soaking them in a scorching bath of trans fats in the deep fryer from the hydrogenated oils that are typically used.

Keep in mind that potatoes contain so many vitamins and minerals that the list is way too long to even try. Also, as long as you eat the skins, you get a decent shot of fiber too.


8. I take it for other reasons but this is good to know:


Alternatives To Halt High Blood Pressure

The shining star among supplements is coenzyme Q10, an enzyme involved in energy production that also acts as an antioxidant. Patients with hypertension tend to have lower levels of the enzyme, and a meta-analysis – an overarching analysis of past studies – found that treatment with coenzyme Q10 supplements significantly reduced blood pressure.




9. My cycling is slow and steady (what little I do of it - I really, really need to do more), but at least my running on the soccer field is often intense:

Cycling fast: vigorous daily exercise recommended for a longer life

A study conducted among cyclists in Copenhagen, Denmark1 showed that it is the relative intensity and not the duration of cycling which is of most importance in relation to all-cause mortality and even more pronounced for coronary heart disease mortality.


10. Eating dark chocolate (86%) is one of the things I do best:

Chocolate reduces the risk of cardiovascular disease and stroke


Five studies reported a beneficial link between higher levels of chocolate consumption and the risk of cardiovascular events and they found that the "highest levels of chocolate consumption were associated with a 37% reduction in cardiovascular disease and a 29% reduction in stroke compared with lowest levels." No significant reduction was found in relation to heart failure.


11. More research directly related to my diet:

Why White Bread is Bad for You

Breast cancer risk drops when diet includes walnuts

Friday, September 16, 2011

An Apple or Pear a Day May Keep Strokes Away

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Apples and pears may keep strokes away.

That's the conclusion of a Dutch study published in Stroke: Journal of the American Heart Association in which researchers found that eating a lot of fruits and vegetables with white flesh may protect against stroke.

While previous studies have linked high consumption of fruits and vegetables with lower stroke risk, the researchers' prospective work is the first to examine associations of fruits and vegetable color groups with stroke.

The color of the edible portion of fruits and vegetables reflects the presence of beneficial phytochemicals such as carotenoids and flavonoids.

Researchers examined the link between fruits and vegetable color group consumption with 10-year stroke incidence in a population-based study of 20,069 adults, with an average age of 41. The participants were free of cardiovascular diseases at the start of the study and completed a 178-item food frequency questionnaire for the previous year.

Fruits and vegetables were classified in four color groups:

* Green, including dark leafy vegetables, cabbages and lettuces
* Orange/Yellow, which were mostly citrus fruits
* Red/Purple, which were mostly red vegetables
* White, of which 55 percent were apples and pears

During 10 years of follow-up, 233 strokes were documented. Green, orange/yellow and red/purple fruits and vegetables weren't related to stroke. However, the risk of stroke incidence was 52 percent lower for people with a high intake of white fruits and vegetables compared to people with a low intake.

Each 25 gram per day increase in white fruits and vegetable consumption was associated with a 9 percent lower risk of stroke. An average apple is 120 grams.

"To prevent stroke, it may be useful to consume considerable amounts of white fruits and vegetables," said Linda M. Oude Griep, M.Sc., lead author of the study and a postdoctoral fellow in human nutrition at Wageningen Uninversity in the Netherlands. "For example, eating one apple a day is an easy way to increase white fruits and vegetable intake.

"However, other fruits and vegetable color groups may protect against other chronic diseases. Therefore, it remains of importance to consume a lot of fruits and vegetables."

Apples and pears are high in dietary fiber and a flavonoid called quercetin. In the study, other foods in the white category were bananas, cauliflower, chicory and cucumber.

Potatoes were classified as a starch.

Previous research on the preventive health benefits of fruits and vegetables focused on the food's unique nutritional value and characteristics, such as the edible part of the plant, color, botanical family and its ability to provide antioxidants.

U.S. federal dietary guidelines include using color to assign nutritional value. The U.S. Preventive Health Services Taskforce recommends selecting each day vegetables from five subgroups: dark green, red/orange, legume, starchy and other vegetables.

Before the results are adopted into everyday practice, the findings should be confirmed through additional research, Oude Griep said. "It may be too early for physicians to advise patients to change their dietary habits based on these initial findings," she said.

An accompanying editorial notes that the finding should be interpreted with caution because food frequency questionnaires may not be reliable.

In addition, "the observed reduction in stroke risk might further be due to a generally healthier lifestyle of individuals consuming a diet rich in fruits and vegetables," writes Heike Wersching, M.D., M.Sc., of Institute of Epidemiology and Social Medicine at the University of Münster, in Germany.

Thursday, September 15, 2011

Probiotics Have Slight Preventive Effect on Colds: Review

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Taking probiotics seems to provide both children and adults with a mild degree of protection against many upper respiratory tract infections (URTI) including the common cold, according to a new systematic review. People who consume probiotics are also less likely to end up taking antibiotics for an upper respiratory infection, the review found.

Probiotics are in fermented foods like yogurt, soy yogurt and kefir. People also often take probiotics as supplements. The reviewers compared how often colds and other respiratory infections occurred in people who consumed probiotics to people who took placebos and found a statistically significant difference.

“Probiotics intervention was better than placebo in reducing the number of participants experiencing episodes of acute upper respiratory tract infections,” said review co-author Qiukui Hao in an email “Limited information from three of the 14 studies we included in our analysis also showed that probiotics can reduce the prescription of antibiotics.”

Hao is a medical student at Sichuan University in China, where he works with lead review author Bi Rong Dong, M.D.

Colds and other upper respiratory infections are the most common reason that people in the United States seek medical care, the reviewers say. The average American has two to six colds each year, which usually are mild viral infections that resolve themselves after a few days.

Upper respiratory infections also include tonsillitis, laryngitis and pharyngitis, an inflammation of the pharynx and the most common cause of a sore throat. Other frequently occurring upper respiratory infections are acute sinusitis, acute middle ear infection and croup. Symptoms including nasal congestion, sore throats, hoarseness and coughing.

The researchers based their conclusions on 14 randomized controlled trials that included 3,451 participants. More than two-thirds of participants were children. The average age of adult participants was 40. Studies took place in Australia, Chile, Croatia, Finland, Japan, Spain, Sweden and the United States.

Probiotics include a wide variety of live active microorganisms such as lactic acid bacteria, also called lactobacillus, and bifidobacteria. The review considered any probiotic, whether it was a single strain or multiple strains, at any dosage level for more than seven days.

There was no difference in how long a respiratory infection lasted in the probiotics group compared to the group consuming placebos. Participants taking probiotics experienced only a few minor side effects. These were mostly gastrointestinal symptoms such as vomiting, flatulence and discomfort or pain in the lower intestinal region. When studying all of the pooled data, the researchers found no significant differences in the occurrence of such side effects among people taking probiotics and those taking placebo.

The review appears in the current issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.
In Greek, the word “probiotics” means “for life.” Qiukui Hao said that more than a century ago, Elie Metchnikoff, a Nobel Prize-winning researcher in immunology, ran a series of studies that showed that the ingestion of microbes produced by lactic acid – that is, probiotics – could help relive both respiratory tract and digestive disorders.

However, more recent studies focusing on the affects of probiotics upon URTIs have been inconclusive, Hao said. “With the increasing consumption of probiotics in fermented foods or as dietary supplements, we feel that it is very important to understand the effects of probiotics on acute URTIs and their potential adverse effects in humans.”

Mohamed Mubasher, Ph.D., a former associate professor of Biostatistics at the University of Texas, said, “What's exciting about this research is the fact that probiotics, a drug-free natural product, can potentially boost and enhance the human immune system and also regulate the production of beneficial bacteria within the human system.”

Mubasher said that he considered the authors of this review to have competently evaluated the results of the 14 studies they reviewed. However, he added that with regard to reducing the duration of URTIs, he suspected that many of the studies covered by this analysis were of insufficient sample size to adequately support such claims.

He also noted a drawback, which the authors had themselves acknowledged: Elderly adults were not included among the study participants. As people age, their immune systems weaken. Older adults might stand to benefit significantly from immune system enhancements, even mild ones such as those that probiotics seem to offer to younger people

Tuesday, September 13, 2011

Link between high cholesterol and Alzheimer's disease

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People with high cholesterol may have a higher risk of developing Alzheimer's disease, according to a study published in the September 13, 2011, issue of Neurology®, the medical journal of the American Academy of Neurology.

"We found that high cholesterol levels were significantly related to brain plaques associated with Alzheimer's disease," said study author Kensuke Sasaki, MD, PhD, of Kyushu University in Fukuoka, Japan.

For the study, the cholesterol levels were tested for 2,587 people age 40 to 79 who had no signs of Alzheimer's disease. Then they examined 147 autopsied people who died after a long observation period (10 to 15 years). Of those, 50 people, or 34 percent, had been diagnosed with dementia before death.

The autopsies looked for plaques and tangles in the brain, both known to be trademark signs of Alzheimer's disease. Plaques are an accumulation of a form of the protein amyloid, which occurs between nerve cells. Tangles are an accumulation of a different protein, called tau, which occurs inside nerve cells.

People with high cholesterol levels, defined by a reading of more than 5.8 mmol/L, had significantly more brain plaques when compared to those with normal or lower cholesterol levels. A total of 86 percent of people with high cholesterol had brain plaques, compared with only 62 percent of people with low cholesterol levels.

The study found no link between high cholesterol and the tangles that develop in the brain with Alzheimer's disease.

In addition to high cholesterol increasing the risk of Alzheimer's disease, Sasaki previously found that insulin resistance, a sign of diabetes, may be another risk factor for brain plaques associated with Alzheimer's disease.

"Our study clearly makes the point that high cholesterol may contribute directly or indirectly to plaques in the brain," Sasaki said, "but failed treatment trials of cholesterol-lowering drugs in Alzheimer's disease means there is no simple link between lowering cholesterol and preventing Alzheimer's."

Long-term use of nonaspirin anti-inflammatory drugs and renal cell cancer

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Long-term use of nonaspirin anti-inflammatory drugs (NSAIDs) is associated with an increased risk of renal cell cancer (RCC), according to a report in the September issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

According to background information in the article, in the United States, kidney cancer is the seventh leading type of cancer among men and the ninth leading type of cancer among women. The most common type of kidney cancer, renal cell cancer, accounts for 85 percent of all cases. Analgesics (pain-relieving medications) are among the most commonly used groups of drugs in the United States, and some appear to have protective effects against cancer. "However," the authors write, "some epidemiologic data, mainly from case-control studies, suggest an association between analgesic use and an increased risk of RCC."

Eunyoung Cho, Sc.D., from Harvard Medical School and Brigham and Women's Hospital, Boston, and colleagues examined the relationship between analgesic use and RCC risk. They used data from the Nurses' Health Study and the Health Professionals Follow-up Study, both prospective cohort studies. Beginning in 1990 in the Nurses' Health Study and 1986 in the Health Professionals Follow-up Study, and every two years thereafter, use of aspirin, other NSAIDs and acetaminophen was determined. Follow-up was 16 years and 20 years, respectively. The researchers evaluated the baseline and duration of use of analgesics. They also assessed other risk factors for RCC, such as body weight, smoking, recreational physical activity and history of hypertension.

Among the 77,525 women and 49,403 men included in the study, the researchers documented 333 RCC cases. No association was found between aspirin and acetaminophen use and RCC risk. An association was found between regular use of nonaspirin NSAIDs and an increased risk of RCC, with a 51 percent increase in the relative risk. The researchers noticed a dose-response relationship between duration of nonaspirin NSAID use and RCC risk; there was a 19 percent decrease in relative risk for use less than four years, a 36 percent increase in relative risk for use of analgesics for four years to less than 10 years and nearly three times the relative risk for use for 10 or more years.

Even low-dose aspirin may increase risk of GI bleeding

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The risk of gastrointestinal (GI) bleeding needs to be considered when determining the potential preventive benefits associated with low-dose aspirin for cardiovascular disease and cancer. According to a new study in Clinical Gastroenterology and Hepatology, the use of low-dose aspirin increases the risk for GI bleeding, with the risk being increased further with accompanying use of cardiovascular disease-preventing therapies, such as clopidogrel and anticoagulants. In patients who took proton pump inhibitors (PPIs), bleeding risk decreased. Clinical Gastroenterology and Hepatology is the official journal of the American Gastroenterological Association.

"The use of aspirin has been proven beneficial in reducing cardiac events and deaths in patients who have cardiovascular disease, and has even been shown to reduce cancer risk," said Angel Lanas, MD, PhD, of University Hospital Lozano Blesa and lead author of this study. "However, clinicians need to be more proactive in their efforts to reduce potential risk factors associated with all doses of aspirin, especially gastrointestinal bleeding. New low-dose aspirin studies should report more precisely on the incidence of bleedings, especially gastrointestinal bleedings, to better determine the balance between risks and benefits ."

Low-dose aspirin — commonly defined as 75 to 325 mg daily — is a mainstay of therapy for cardiovascular disease. In fact, patients with prior cardiovascular disease have fewer cardiovascular events and deaths with the use of low-dose aspirin compared with patients who do not use it. It is now likely to also be used for cancer prevention, especially GI and colon cancer.

A major factor limiting the widespread use of aspirin is concern about the development of GI adverse events, especially GI bleeding. However, damage may vary depending on the dose taken, other medication being consumed along with aspirin and patients' risk profiles. For example, certain patients have an increased likelihood of experiencing bleeding: those with long-term pharmacotherapy use, patients using combinations of low-dose aspirin with clopidogrel and anticoagulants, and patients with previous GI ulcers or bleedings.

In this study, doctors searched 10 electronic databases and collected data on adverse events in studies that evaluated low doses of aspirin alone or in combination with anticoagulants, clopidogrel or PPIs. They found that low doses of aspirin alone decreased the risk of death. However, the risk of major GI bleeding increased with low doses of aspirin alone compared with placebo. The risk also increased when aspirin was combined with clopidogrel (compared with aspirin alone), anticoagulants versus low doses of aspirin alone, or in studies that included patients with a history of GI bleeding or of longer duration. Importantly, PPI use reduced the risk for major GI bleeding in patients given low doses of aspirin.

Primary component in turmeric kicks off cancer-killing mechanisms in human saliva

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Study could have an impact in fighting head and neck cancers


Curcumin, the main component in the spice turmeric, suppresses a cell signaling pathway that drives the growth of head and neck cancer, according to a pilot study using human saliva by researchers at UCLA's Jonsson Comprehensive Cancer Center.

The inhibition of the cell signaling pathway also correlated with reduced expression of a number of pro-inflammatory cytokines, or signaling molecules, in the saliva that promote cancer growth, said Dr. Marilene Wang, a professor of head and neck surgery, senior author of the study and a Jonsson Cancer Center researcher.

"This study shows that curcumin can work in the mouths of patients with head and neck malignancies and reduce activities that promote cancer growth," Wang said. "And it not only affected the cancer by inhibiting a critical cell signaling pathway, it also affected the saliva itself by reducing pro-inflammatory cytokines within the saliva."

The study appears Sept. 15 in Clinical Cancer Research, a peer-reviewed journal of the American Association of Cancer Research.

Turmeric is a naturally occurring spice widely used in South Asian and Middle Eastern cooking and has long been known to have medicinal properties, attributed to its anti-inflammatory effects. Previous studies have shown it can suppress the growth of certain cancers. In India, women for years have been using turmeric as an anti-aging agent rubbed into their skin, to treat cramps during menstruation and as a poultice on the skin to promote wound healing.

A 2005 study by Wang and her team first showed that curcumin suppressed the growth of head and neck cancer, first in cells and then in mouse models. In the animal studies, the curcumin was applied directly onto the tumors in paste form. In a 2010 study, also done in cells and in mouse models, the research team found that the curcumin suppressed head and neck cancer growth by regulating cell cycling, said scientist Eri Srivatsan, an adjunct professor of surgery, article author and a Jonsson Cancer Center researcher who, along with Wang, has been studying curcumin and its anti-cancer properties for seven years.

The curcumin binds to and prevents an enzyme known as IKK, an inhibitor of kappa β kinase, from activating a transcription factor called nuclear factor kappa β (NFκβ), which promotes cancer growth.

In this study, 21 patients with head and neck cancers gave samples of their saliva before and after chewing two curcumin tablets totaling 1,000 milligrams. One hour later, another sample of saliva was taken and proteins were extracted and IKKβ kinase activity measured. Thirteen subjects with tooth decay and five healthy subjects were used as controls, Wang said.

Eating the curcumin, Wang said, put it in contact not just with the cancer but also with the saliva, and the study found it reduced the level of cancer enhancing cytokines.

An independent lab in Maryland was sent blind samples and confirmed the results - the pro-inflammatory cytokines in the saliva that help feed the cancer were reduced in the patients that had chewed the curcumin and the cell signaling pathway driving cancer growth was inhibited, Wang said.

"The curcumin had a significant inhibitory effect, blocking two different drivers of head and neck cancer growth," Wang said. "We believe curcumin could be combined with other treatments such as chemotherapy and radiation to treat head and neck cancer. It also could perhaps be given to patients at high risk for developing head and neck cancers – smokers, those who chew tobacco and people with the HPV virus – as well as to patients with previous oral cancers to fight recurrence."

The curcumin was well tolerated by the patients and resulted in no toxic effects. The biggest problem was their mouths and teeth turned bright yellow.

"Curcumin inhibited IKKβ kinase activity in the saliva of head and neck cancer patients and this inhibition correlated with reduced expression of a number of cytokines," the study states. "IKKβ kinase could be a useful biomarker for detecting the effects of curcumin in head and neck cancer."

To be effective in fighting cancer, the curcumin must be used in supplement form. Although turmeric is used in cooking, the amount of curcumin needed to produce a clinical response is much larger. Expecting a positive effect through eating foods spiced with turmeric is not realistic, Wang said.

The next step for Wang and her team is to treat patients with curcumin for longer periods of time to see if the inhibitory effects can be increased. They plan to treat cancer patients scheduled for surgery for a few weeks prior to their procedure. They'll take a biopsy before the curcumin is started and then at the time of surgery and analyze the tissue to look for differences.

"There's potential here for the development of curcumin as an adjuvant treatment for cancer," Wang said. "It's not toxic, well tolerated, cheap and easily obtained in any health food store. While this is a promising pilot study, it's important to expand our work to more patients to confirm our findings."

Finding ways to better treat head and neck cancers is vital as patients often require disfiguring surgery, often losing parts of their tongue or mouth. They also experience many side effects, including difficulty swallowing, dry mouth and have the potential for developing another oral cancer later.

Spicing up broccoli boosts its cancer-fighting power

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Teaming fresh broccoli with a spicy food that contains the enzyme myrosinase significantly enhances each food's individual cancer-fighting power and ensures that absorption takes place in the upper part of the digestive system where you'll get the maximum health benefit, suggests a new University of Illinois study.

"To get this effect, spice up your broccoli with broccoli sprouts, mustard, horseradish, or wasabi. The spicier, the better; that means it's being effective," said Elizabeth Jeffery, a U of I professor of nutrition.

In the study, when fresh broccoli sprouts were eaten with broccoli powder, the scientists were able to measure bioactive compounds in the blood 30 minutes later. When these peaked at three hours, they were much higher when the foods were eaten together than when either was eaten alone. Urine samples corroborated the blood results, said Jenna Cramer, lead author of the study.

It's no secret that many people cook the benefits right out of broccoli instead of steaming it lightly for two to four minutes to protect its healthful properties, she said.

"However, this study shows that even if broccoli is overcooked, you can still boost its benefits by pairing it with another food that contains myrosinase," she said.

Myrosinase is the enzyme necessary to form sulforaphane, the vegetable's cancer-preventive component, co-author Margarita Teran-Garcia explained.

Note what happened with the fresh broccoli sprouts and broccoli powder eaten in this experiment. The powder doesn't contain myrosinase, but it does contain the precursor to the anti-cancer agent sulforaphane. Eaten together, the sprouts were able to lend their myrosinase to the powder. As predicted, both foods produced sulforaphane and provided greater anti-cancer benefit, Jeffery said.

Other foods that will boost broccoli's benefits if they are paired together include radishes, cabbage, arugula, watercress, and Brussels sprouts.

"Here's another benefit of protecting and enhancing the myrosinase in your foods," Jeffery said. "If myrosinase is present, sulforaphane is released in the ilium, the first part of your digestive system. Absorption happens well and quickly there, which is why we saw bioactivity in 30 minutes."

An earlier Jeffery study showed that microbiota are capable of releasing sulforaphane in the lower gut, but absorption happens more slowly in the colon than in the upper intestine, she said.

Scientists say that as little as three to five servings of broccoli a week provide a cancer-protective benefit.

"But it pays to spice it up for added benefits and find ways to make it appealing so you don't mind eating it if you're not a broccoli fan. I add fresh broccoli sprouts to sandwiches and add them as one of my pizza toppings after the pie is out of the oven," Cramer said.

Put the so-called "Talk Test" to the test

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New research by University of New Hampshire exercise scientists confirms that a low-tech, easy-to-administer test is an effective tool for gauging exercise intensity, but that it does not correspond as neatly as previously assumed to other more objective tests. In a study published recently in the Journal of Sports Sciences, UNH associate professor of kinesiology Timothy Quinn and his former graduate student Benjamin Coons put the so-called "Talk Test" to the test.

Quinn and Coons set out to learn just how good this test, gaining in popularity over the past decade, is, and how it compared to two other laboratory-tested measures of intensity, the lactate threshold and the ventilatory threshold.

The researchers administered the Talk Test to healthy adults, having them read the Pledge of Allegiance while exercising at different intensities and rating how comfortable they were speaking. They found that when participants reported a positive Talk Test – that they could still speak comfortably – they were exercising at the lower end of established exercise intensity guidelines as measured by both heart rate and maximal oxygen consumption, or VO2 max. When participants became uncertain that they could still speak comfortably, they were exercising at the upper end of intensity guidelines.

This finding confirmed the effectiveness of the Talk Test. "If you can still talk comfortably, you're exercising in a zone that's appropriate for improving fitness in individuals beginning an exercise program," Quinn says. "The Talk Test is a good tool, and it's easy to use."

More surprising, however, was how the Talk Test compared to the lactate threshold, the point at which muscles can no longer metabolize and remove lactic acid as it builds during exercise, and the ventilatory threshold, which is characterized by sudden heavy breathing. While previous research involving the Talk Test has used the ventilatory threshold as the comparator, this study was the first to compare both the lactate and ventilatory thresholds with the Talk Test. Data showed that the Talk Test related best to the lactate threshold as compared to the ventilatory threshold

"Everybody's thought that the Talk Test related well to the ventilatory threshold," Quinn says. "And it does, to a certain degree. But different physiological phenomena occur at each threshold, and it is the phenomena associated with the lactate threshold that relate better to the different levels of the Talk Test."

Quinn says these findings on the relationship of the Talk Test to the lactate threshold make the Talk Test relevant to endurance athletes as well as beginning exercisers. "In order to enhance endurance performance, some training has to occur around the lactate threshold intensity level. When subjects in the study had difficulty talking, they were very close to that lactate threshold intensity. Because of this, athletes could gauge their intensity based on ability to talk comfortably."

"If you are beginning an exercise program and can still talk while you're exercising, you're doing OK," Quinn says. "But if you really want to improve, you've got to push a little bit harder."

Relation of alcohol consumption to colorectal cancer

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A meta-analysis of case-control and cohort studies on the association of alcohol consumption with colorectal cancer was carried out, based on 22 studies from Asia, 2 from Australia, 13 from Western Europe, and 24 from North America. The paper provides evidence that alcohol, at least at higher levels of consumption, is associated with an increase in the risk of colorectal cancer. Overall, there was no increase in the risk for consumers reporting an average intake of up to 1 drink per day, but an increase (of 21%) for what the authors defined as "moderate drinking" (averaging up to 49.9 g of alcohol – far in excess of all responsible drinking guidelines ). The increase in risk was greater (52%) for consumers of 50 or more grams of alcohol per day.

Forum reviewers thought that this was, in general, a very well-done study that used appropriate statistical techniques for meta-analysis. There were some key concerns, however, including the following: (1) the authors' definition of "moderate drinking" extended well above the usual recommended limits for sensible drinking; effects of consumption in categories of 1 to 2 drinks/day, 2 to 3 drinks/day, etc., were not given; (2) no results were provided according to type of beverage even though many previous studies have shown differences between health effects for consumers of wine, or wine/beer, and other beverages; and (3) no data were available on the pattern of drinking. Many studies have shown that regular, moderate drinking on most days of the week has very different health outcomes than drinking only on week-ends or binge drinking.

Despite these concerns, Forum members agreed that current data indicate that alcohol intake, especially heavier drinking, is associated with an increase in the risk of colorectal cancers. Future studies are needed to help determine if there is a threshold level of alcohol that increases the risk, if there are differences by type of beverage, and if the pattern of drinking (regular versus binge drinking) affects the risk.

Thursday, September 8, 2011

Alcohol intake and 'successful aging'

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Among 13,894 women in the Nurses' Health Study, investigators prospectively examined alcohol use assessed at midlife in relation to "successful ageing," which was defined as survival to age 70 years, not having a major chronic disease (such as coronary disease, cancer, stroke, diabetes), and having no major cognitive impairment, physical impairment, or mental health problems. Only 11% of the women met these criteria.

The results indicate that moderate drinkers, especially those consuming wine and drinking regularly, were more likely to exhibit successful ageing. For average amount consumed, the largest benefit (an increase of 28%) was among women who reported 15.1 – 30 g of alcohol per day (an average of just over 1 to 2 ½ drinks per day), when compared with non-drinkers. The frequency of drinking was especially important: in comparison with nondrinkers, women who drank only on 1 to 2 days per week had little increase in their risk of successful ageing, but those drinking on at least 5 days per week had almost a 50% greater chance of successful ageing.

Forum reviewers had some questions about the definition of "successful ageing" used in this study. It is believed that a much greater percentage of people who may not meet these criteria make huge contributions to society and should be considered "successful."

In summary, these results support the findings of earlier studies showing that many aspects of successful ageing, in addition to just survival, are favorably affected by regular, moderate consumption of alcohol.

One Drink a Day = Good Overall Health in Women

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Women who drink 15 grams or less of alcohol a day (the equivalent of one drink of any alcoholic beverage) at midlife may be healthier when older than women who do not drink at all, who consume more than two drinks a day, or who consume four drinks or more at the one time, according to a new study.

A study led by Qi Sun from the Harvard School of Public Health and the Brigham and Women's Hospital in Boston, USA, and published in this week's PLoS Medicine suggests that in women, regular, moderate alcohol consumption during middle age (average age 58 years) is related to good overall health -- that is, having no major chronic diseases, such as heart disease or diabetes, and no major cognitive and physical impairment, or mental health limitations -- in those who live to 70 years and beyond. The authors define this good overall health as "successful aging."

The authors used information from periodic food frequency questionnaires given to the 121,700 female nurses enrolled in the US Nurses' Health Study (which began in 1976) to assess the alcohol consumption of the nurses during middle age. The authors then included in their analysis the vast majority (98.1%) of participants who were not heavier drinkers (45 g/d) when middle-aged and examined the health status in the 13,984 women who lived to 70 years and over.

After discounting other factors, such as smoking, that might affect their health status, the authors found that women who drank 5-15 g of alcohol per day (between a 1/3 and 1 drink per day) had about a 20% higher chance of good overall health when older compared to non-drinkers. Furthermore, women who drank alcohol regularly had a better chance of good overall health when older than occasional drinkers: compared to women who didn't drink, women who drank five to seven days a week had almost 50% greater chance of good overall health when older.

The authors conclude: "These data suggest that regular, moderate consumption of alcohol at midlife may be related to a modest increase in overall health status among women who survive to older ages."

They add: "The 2010 US Department of Agriculture dietary guidelines note that moderate alcohol consumption of up to one drink per day for women and up to two drinks per day for men may provide health benefits in some people. Our data support this recommendation and provide novel evidence suggesting that light-to-moderate alcohol consumption at the levels of one to two drinks/day or slightly less at midlife may benefit overall health at older ages in US women."

Exercise at Work Boosts Productivity

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Devoting work time to physical activity can lead to higher productivity, according to a study performed by researchers at Stockholm University and Karolinska Institutet that is being published in Journal of Occupational and Environmental Medicine.

The study shows that it is possible to use work time for exercise or other health-promoting measures and still attain the same or higher production levels. The same production levels with fewer work hours means greater productivity, while at the same time individuals benefit from better health as a result of the physical activity.

"This increased productivity comes, on the one hand, from people getting more done during the hours they are at work, perhaps because of increased stamina and, on the other hand, from less absenteeism owing to sickness," says Ulrica von Thiele Schwarz and Henna Hasson, the researchers behind the study.

In the study, two workplaces in dental care were asked to devote 2.5 hours per week to physical activity, distributed across two sessions. Another group had the same decrease in work hours but without obligatory exercise, and a third group maintained their usual work hours, 40 hours a week.

The results showed that all three groups were able to maintain or even increase their production level, in this case the number of patients treated, during the study period compared with the corresponding time the previous year. Those who exercised also reported improvements in self-assessed productivity -- they perceived that they got more done at work, had a greater work capacity, and were sick less often.

Wednesday, September 7, 2011

Aerobic Exercise May Reduce the Risk of Dementia

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Any exercise that gets the heart pumping may reduce the risk of dementia and slow the condition’s progression once it starts, reported a Mayo Clinic study published this month in Mayo Clinic Proceedings. Researchers examined the role of aerobic exercise in preserving cognitive abilities and concluded that it should not be overlooked as an important therapy against dementia.

The researchers broadly defined exercise as enough aerobic physical activity to raise the heart rate and increase the body’s need for oxygen. Examples include walking, gym workouts and activities at home such as shoveling snow or raking leaves.

“We culled through all the scientific literature we could find on the subject of exercise and cognition, including animal studies and observational studies, reviewing over 1,600 papers, with 130 bearing directly on this issue. We attempted to put together a balanced view of the subject,” says J. Eric Ahlskog, M.D., Ph.D., a neurologist at Mayo Clinic. “We concluded that you can make a very compelling argument for exercise as a disease-modifying strategy to prevent dementia and mild cognitive impairment, and for favorably modifying these processes once they have developed.”

The researchers note that brain imaging studies have consistently revealed objective evidence of favorable effects of exercise on human brain integrity. Also, they note, animal research has shown that exercise generates trophic factors that improve brain functioning, plus exercise facilitates brain connections (neuroplasticity).

More research is needed on the relationship between exercise and cognitive function, the study’s authors say, but they encourage exercise, in general, especially for those with or worried about cognitive issues.