Tuesday, December 27, 2011
A compound produced from fish oil that appears to target leukemia stem cells could lead to a cure for the disease, according to Penn State researchers.
The compound -- delta-12-protaglandin J3, or D12-PGJ3 -- targeted and killed the stem cells of chronic myelogenous leukemia, or CML, in mice, said Sandeep Prabhu, associate professor of immunology and molecular toxicology in the Department of Veterinary and Medical Sciences. The compound is produced from EPA -- Eicosapentaenoic Acid -- an Omega-3 fatty acid found in fish and in fish oil, he said.
"Research in the past on fatty acids has shown the health benefits of fatty acids on cardiovascular system and brain development, particularly in infants, but we have shown that some metabolites of Omega-3 have the ability to selectively kill the leukemia-causing stem cells in mice," said Prabhu. "The important thing is that the mice were completely cured of leukemia with no relapse."
The researchers, who released their findings in the current issue of Blood, said the compound kills cancer-causing stem cells in the mice's spleen and bone marrow. Specifically, it activates a gene -- p53 -- in the leukemia stem cell that programs the cell's own death.
"p53 is a tumor suppressor gene that regulates the response to DNA damage and maintains genomic stability," Prabhu said.
Killing the stem cells in leukemia, a cancer of the white blood cells, is important because stem cells can divide and produce more cancer cells, as well as create more stem cells, Prabhu said.
The current therapy for CML extends the patient's life by keeping the number of leukemia cells low, but the drugs fail to completely cure the disease because they do not target leukemia stem cells, said Robert Paulson, associate professor of veterinary and biomedical sciences, who co-directed this research with Prabhu.
"The patients must take the drugs continuously," said Paulson. "If they stop, the disease relapses because the leukemia stem cells are resistant to the drugs."
Current treatments are unable to kill the leukemia stem cells, Paulson said.
"These stem cells can hide from the treatment, and a small population of stem cells give rise to more leukemia cells," said Paulson. "So, targeting the stem cells is essential if you want to cure leukemia."
During the experiments, the researchers injected each mouse with about 600 nanograms of D12-PGJ3 each day for a week. Tests showed that the mice were completely cured of the disease. The blood count was normal, and the spleen returned to normal size. The disease did not relapse.
In previous experiments, the compound also killed the stem cells of Friend Virus-induced leukemia, an experimental model for human leukemia.
The researchers focused on D12-PGJ3 because it killed the leukemia stem cells, but had the least number of side effects. The researchers currently are working to determine whether the compound can be used to treat the terminal stage of CML, referred to as Blast Crisis. There are currently no drugs available that can treat the disease when it progresses to this stage.
The researchers, who applied for a patent, are also preparing to test the compound in human trials.
Researchers have linked increased starch intake to a greater risk for breast cancer recurrence.
"The results show that it's not just overall carbohydrates, but particularly starch," said Jennifer A. Emond, M.S., a public health doctoral student at the University of California, San Diego. "Women who increased their starch intake over one year were at a much likelier risk for recurring."
Researchers conducted a subset analysis of 2,651 women who participated in the Women's Healthy Eating and Living (WHEL) Dietary Intervention Trial, a plant-based intervention trial that enrolled about 3,088 survivors of breast cancer. WHEL researchers studied breast cancer recurrence and followed the participants for an average of seven years.
The subset analysis involved an examination of how changes in carbohydrate intake influenced breast cancer recurrence. "The WHEL dietary trial, even though it focused on fruits and vegetables, fiber and fat, didn't really have a specific carbohydrate goal," Emond said.
She and her colleagues obtained carbohydrate intake information from multiple 24-hour dietary recalls at baseline and at one year. In an annual phone interview, participants reported everything they had eaten during the last 24 hours. At baseline, carbohydrate intake was 233 grams per day. Results showed that women whose cancer recurred had a mean increase in carbohydrate intake of 2.3 grams per day during the first year, while women whose cancer did not recur reported a mean decrease of 2.7 grams per day during the first year.
Starches were particularly important, Emond said. Changes in starch intake accounted for 48 percent of the change in carbohydrate intake. Mean change in starch intake during the first year was -4.1 grams per day among women whose cancer recurred vs. -8.7 grams per day among women whose cancer did not recur.
When change in starch intake during one year was grouped into quartiles of change, the rate of an additional breast cancer event was 9.7 percent among women who decreased their starch intake the most during one year, compared with an event rate of 14.2 percent among women who increased their starch intake the most during one year.
The change in starch intake was "independent of dietary changes that happened in the intervention arm," Emond said. "It is independent of more global changes in diet quality."
After stratifying patients by tumor grade, Emond and colleagues found that the increased risk was limited to women with lower-grade tumors.
These results indicate a need for more research on dietary recommendations that consider limited starch intake among women with breast cancer.
Saturday, December 24, 2011
Scientists at the University of Granada have shown that oleic acid and hydroxytyrosol –present in a particularly high concentration in virgin olive oil– and n-3 polyunsaturated fatty acids –found in fish– relieve the symptoms of pancreatitis.
The researchers evaluated the role of Mediterranean diet ingredients in the prevention and mitigation of cell damage.
Oleic acid and hydroxytyrosol –present in a particularly high concentration in virgin olive oil– and n-3 polyunsaturated fatty acids –found in fish– affect the cellular mechanisms involved in the development of acute pancreatitis, a disease of oxidative-inflammatory etiology. Therefore, oleic acid and hydroxytyrosol can be considered potential functional ingredients, as they may prevent or mitigate this disease.
Such was the conclusion drawn in a study conducted by a research group at the University of Granada Physiology Department, where the researchers examined the role of the Mediterranean diet ingredients in the prevention and mitigation of cell damage.
An In Vitro Experimental Model
These scientists developed an in vitro experimental model that allows scientist to evaluate how changes in the membrane fatty acid composition in vivo –caused by a change in the type of fat ingested– affect the ability of cells to respond to induced oxidative-inflammatory damage with cerulein (acute pancreatitis).
This is the first study to examine how fatty acids and antioxidants affect the cellular mechanisms that respond to local inflammation in the pancreas. The University of Granada scientists have evaluated the role of antioxidants from a preventive approach, that is, by using an experimental model in mice in which cell damage is induced after pretreatment with these nutritional components.
The author of this study, María Belén López Millán affirms that "there is increasing evidence that there are oxidative-inflammatory processes involved in the origin of chronic diseases and that diet plays an important role in such processes. The antioxidant (phenolic compounds) and antiinflammatory (omega-3 fatty acids) effects of diet components (nutrients and bioactive compounds) prevent/mitigate the pathological incidence of oxidative-inflammatory processes".
The author reminds us that the Mediterranean diet has been recognized by the UNESCO as Intangible Cultural Heritage “and it is important to provide scientific evidence that explains its beneficial effects on health”.
The results of this study –which has been coordinated by professors Mariano Mañas Almendros, María Dolores Yago Torregrosa and María Dolores Mesa García– have been partially published in the journal Proceedings of the Nutrition Society.
Wednesday, December 21, 2011
Vitamin B therapy was once widely used to lower homocysteine levels. Too much of this amino acid in the bloodstream was linked to increased risk of stroke and heart attack. But several randomized trials found lowering homocysteine levels with B vitamins did not result in a cardiovascular benefit. And a study by Dr. Spence, a scientist with the Robarts Research Institute at Western's Schulich School of Medicine & Dentistry, found Vitamin B therapy actually increased cardiovascular risk in patients with diabetic nephropathy.
Dr. Spence says this commentary provides insights that overturn the widespread belief that "homocysteine is dead." He says two key issues have been overlooked in the interpretation of the clinical trials: the key role of vitamin B12, and the newly recognized role of renal failure.
"It is now clear that the large trials showing no benefit of vitamin therapy obscured the benefit of vitamin therapy because they lumped together patients with renal failure and those with good renal function. The vitamins are harmful in renal failure, and beneficial in patients with good renal function, and they cancel each other out," says Dr. Spence, the author of "How to Prevent Your Stroke." The authors also contend most of the trials did not use a high enough dose of vitamin B12.
Tuesday, December 20, 2011
Wine consumers, especially in comparison with spirits drinkers, have been shown to have higher levels of education and income, to consume a healthier diet, be more physically active, and have other characteristics that are associated with better health outcomes. However, epidemiologic studies have been inconsistent in showing that, after adjustment for all associated lifestyle factors, consumers of wine have lower risk of cardiovascular disease and mortality than do consumers of other beverages.
A study based on the long-term follow up of a group of older Americans concluded that the associated lifestyle habits and environmental factors of wine consumers largely explained their better health outcomes. Forum reviewers were concerned about some of the methodological approaches used, and believed that the data presented in the paper were inadequate to support such a conclusion. This was a small study, had only a single estimate of alcohol intake (at baseline but not throughout 20 years of follow up), and the authors may have over-adjusted for large differences in lifestyle factors between what they termed as "low-wine" and "high-wine" consumers. The study did confirm a lower mortality risk for alcohol consumers than for non-drinkers.
Experimental studies have clearly indicated that the polyphenols and other constituents that are present in wine and some beers have independent protective effects against most cardiovascular risk factors. Whether or not such advantages are seen among moderate drinkers of wine (or beer) in epidemiologic studies is difficult to determine, as comparisons are not being made between wine, beer, and spirits but between humans who consume one or other such beverage. In almost all populations, drinkers of a specific beverage differ in many ways other than just the type of beverage they consume.
A Mediterranean diet with large amounts of vegetables and fish gives a longer life. This is the unanimous result of four studies to be published by the Sahlgrenska Academy at the University of Gothenburg. Research studies ever since the 1950s have shown that a Mediterranean diet, based on a high consumption of fish and vegetables and a low consumption of animal-based products such as meat and milk, leads to better health.
Study on older people
Scientists at the Sahlgrenska Academy have now studied the effects of a Mediterranean diet on older people in Sweden. They have used a unique study known as the "H70 study" to compare 70-year-olds who eat a Mediterranean diet with others who have eaten more meat and animal products. The H70 study has studied thousands of 70-year-olds in the Gothenburg region for more than 40 years.
Chance of living longer
The results show that those who eat a Mediterranean diet have a 20% higher chance of living longer. "This means in practice that older people who eat a Mediterranean diet live an estimated 2 3 years longer than those who don't", says Gianluca Tognon, scientist at the Sahlgrenska Academy, University of Gothenburg.
Support in other studies
These results are supported by three further as yet unpublished studies into Mediterranean diets and their health effects: one carried out on people in Denmark, the second on people in northern Sweden, and the third on children.
"The conclusion we can draw from these studies is that there is no doubt that a Mediterranean diet is linked to better health, not only for the elderly but also for youngsters", says Gianluca Tognon.
Thursday, December 15, 2011
The Beef in an Optimal Lean Diet (BOLD) clinical study (Effects on Lipids, Lipoproteins and Apolipoproteins),1 conducted by The Pennsylvania State University (PSU) researchers, evaluated adults with moderately elevated cholesterol levels, measuring the impact of diets including varying amounts of lean beef on total and LDL cholesterol levels. Study participants experienced a 10 percent decrease in LDL cholesterol from the start of the study, while consuming diets containing 4.0 and 5.4 oz. of lean beef daily.
"This research sheds new light on evidence supporting lean beef's role in a heart-healthy diet. Study participants ate lean beef every day and still met targets for saturated fat intake," says Penny Kris-Etherton, PhD, RD, distinguished professor of nutrition at PSU and the study's principal investigator. "This study shows that nutrient-rich lean beef can be included as part of a heart-healthy diet that improves risk factors for cardiovascular disease."
The study used a rigorously designed Randomized Controlled Clinical Intervention Study to investigate the effects of cholesterol-lowering diets with varying amounts of lean beef. Thirty-six participants (adults ages 30-65 with moderately elevated cholesterol) were randomly assigned to a treatment order and consumed a total of four diets for five weeks each. The cross-over design allowed each participant to serve as his or her own control, reducing any errors associated with biological variation.
The four diets tested in the study were: Healthy American Diet (HAD) as control; Dietary Approaches to Stop Hypertension (DASH); Beef in Optimal Lean Diet (BOLD); and Beef in Optimal Lean Diet Plus (BOLD-PLUS). Although BOLD and DASH diets were both rich in fruits, vegetables, whole grains and low-fat dairy products, the diets differed in their primary protein source. The BOLD and BOLD-PLUS diet's primary protein source came from lean beef while DASH and HAD included white meat and plant protein. The BOLD diet included an average of 4.0 oz/day of lean beef and the BOLD-PLUS diet included 5.4 oz/day of lean beef, while the HAD and DASH diets included 0.7 and 1.0 oz/day of lean beef, respectively. Many of the BOLD and BOLD-PLUS diet menu plans incorporated recipes from The Healthy Beef Cookbook.
Details on each of the dietary interventions are as follows:
2,097 calories, 17% of calories from protein, 50% of calories from carbohydrate, 33% of calories from fat, 12% of calories from saturated fat, 0.7 oz/day lean beef (weight before cooking)
2,106 calories, 18% of calories from protein, 55% of calories from carbohydrate, 27% of calories from fat, 6% of calories from saturated fat, 1.0 oz/day lean beef (weight before cooking)
2,100 calories, 19% of calories from protein, 54% of calories from carbohydrate, 28% of calories from fat, 6% of calories from saturated fat, 4.0 oz/day lean beef (weight before cooking)
2,104 calories, 27% of calories from protein, 45% of calories from carbohydrate, 28% of calories from fat, 6% of calories from saturated fat, 5.4 oz/day lean beef (weight before cooking)
After five weeks, total cholesterol and LDL cholesterol in the participants were significantly reduced in the BOLD, BOLD-PLUS and DASH diets compared to the HAD diet.
Overall, participants following the BOLD and BOLD-PLUS diets experienced a 10 percent decrease in LDL cholesterol from the start of the study. The improvements in heart health risk factors seen from the BOLD diets were as effective as those from the DASH and other heart-healthy diets, many of which emphasize plant proteins.
This study adds to the body of evidence regarding lean beef in a heart-healthy diet, including a recent review of 20 epidemiological studies encompassing more than one million subjects concluding that red meat intake does not increase risk of heart disease.2
"This research adds to the body of evidence concluding that you can include beef in your diet every day and get heart-health benefits," says Shalene McNeill, PhD, RD, executive director, human nutrition research for the National Cattlemen's Beef Association, which contracts to manage programs for the beef checkoff. "Americans now have more scientific evidence for including lean beef in a heart-healthy diet."
Many of the most popular beef cuts, such as Top Sirloin steak, Tenderloin, T-Bone steak and 95% lean Ground Beef meet government guidelines for lean. In fact, sixty-five percent of all beef muscle cuts available in grocery stores are lean.3,4 On average, a 3 oz. serving of lean beef is about 150 calories, an excellent source of six nutrients (protein, zinc, vitamin B12, vitamin B6, niacin and selenium) and a good source of four nutrients (phosphorous, choline, iron and riboflavin).4
About The Beef Checkoff Program
The Beef Checkoff Program (http://www.MyBeefCheckoff.com) was established as part of the 1985 Farm Bill. The checkoff assesses $1 per head on the sale of live domestic and imported cattle, in addition to a comparable assessment on imported beef and beef products. States retain up to 50 cents on the dollar and forward the other 50 cents per head to the Cattlemen's Beef Promotion and Research Board, which administers the national checkoff program, subject to USDA approval.
About the National Cattlemen's Beef Association
The National Cattlemen's Beef Association is a contractor to the national Beef Checkoff Program, which is administered by the Cattlemen's Beef Board. Consumer-focused and producer-directed, NCBA and its state beef council partners work together as a marketing organization on behalf of the largest segment of the food and fiber industry.
1. Roussell MA, Hill AM, Gaugler TL, West SG, Vanden Heuvel JP, Alaupovic P, Gillies PJ, Kris-Etherton PM. Beef in an Optimal Lean Diet study: effects on lipids, lipoproteins, and apolipoproteins. Am J Clin Nutr 2012; 95(1).Internet: [http://www.ajcn.org/content/early/2011/12/13/ajcn.111.016261.full.pdf+html] (accessed 14 December 2011).
2. Micha R, Wallace SK, Mozaffarian D. Red and processed meat consumption and risk of incident coronary heart disease, stroke, and diabetes mellitus: a systematic review and meta-analysis. Circulation. 2010; 121:2271-2283.
3. Fresh Look Marketing Group, Total US Beef, 52 weeks ending 9/25/2011.
4. USDA, ARS. 2011. USDA National Nutrient Database for Standard Reference, Release 24. Nutrient Data Laboratory Home Page,
In 2011 alone, there has been an abundance of published research from world renowned nutritional scientists and universities, revealing the health benefits of dairy. To name a few:
• According to a U.S. study published in February's Current Nutrition and Food Science, milk provides necessary nutrients without adversely impacting body weight in children and adolescents.
• In Australia, researchers found that consumption of low-fat dairy may help decrease the risk for elevated blood pressure and, regardless of fat content, fluid dairy foods are associated with a reduced risk of elevated blood pressure.
• A French study found a lower incidence of metabolic syndrome, type 2 diabetes and abnormal levels of fasting blood glucose was associated with higher consumption of dairy products and calcium.
• Researchers in Sweden studied more than 15,000 women and found that high-fat diets (including yogurt and regular milk), are associated with a reduced risk of invasive breast cancer.
• Researchers in Australia found that dairy food consumption are not associated with weight gain in children and adults. The review was published in the July Obesity Reviews.
• In Canada, researchers found that women who consumed at least two servings of dairy per day had smaller visceral fat cells compared with women consuming less than two daily servings.
• A May study revealed that dairy intake was not associated with increased heart attack risk in more than 3,000 Costa Rican adults.
• A study of premenopausal African-American women revealed that consuming low-fat and fat-free dairy products may be associated with a lower percent of body fat.
• A Swedish study found that a higher intake of dairy products is associated with a lower risk of cardiovascular disease.
• In Japan, a breakfast that included milk protein was shown to reduce visceral fat by approximately 15%, versus a breakfast that included soy protein that showed no change in fat.
• In October, a Danish study published in the American Journal of Clinical Nutrition showed that cheese does not seem to increase plasma total and LDL-cholesterol concentrations.
A compound that is abundant in apples and strawberries inhibits the highly pathogenic E. coli O157:H7 biofilms while sparing a beneficial strain of E. coli that also forms biofilms in the human gut, according to a paper in the December 2011 issue of the journal Infection and Immunology.
Transcriptome analysis revealed that the compound, called phloretin, suppresses toxin and other genes involved in O157:H7 pathology and biofilm formation. And in a rat model of colitis, phloretin, reduced colon inflammation and body weight loss. "Phloretin has a triple biological activity as an antioxidant compound, a biofilm inhibitor, and an anti-inflammatory agent," says corresponding author Jintae Lee of Yeungnam University, Gyeongsan, Korea.
E. coli O157:H7 causes hemorrhages in the intestine. To date, no effective therapy for O157:H7 biofilms has been found. Biofilms generally are notoriously resistant to antimicrobial therapy. So in the study, Lee screened a dozen flavonoids, including phloretin, for their ability to inhibit these biofilms. "We found that phloretin markedly reduced E. coli O157:H7 biofilm formation on abiotic surface and human colon epithelial cells, while phloretin did not harm commensal E. coli K-12 biofilms," says Lee. Commensal E. coli can actually fortify the human immune system, he says.
In addition to its anti- E. coli O157:H7 biofilm activity, phloretin "accounts in part for the antioxidant capacity of apples, and it also shows anti-inflammatory activity," says Lee. "This study suggests that phloretin in apples could reduce the risk of E. coli O157:H7 infection and intestinal inflammation."
"This study demonstrated for the first time that phloretin, a natural flavonoid, is a nontoxic inhibitor of enterohemorrhagic E. coli O157:H7 biofilms, but does not harm commensal E. coli K-12 biofilms," Lee writes. "Also, importantly, our results confirmed that phloretin shows anti-inflammatory properties in both the in vitro and in vivo inflammatory colitis models. The effect of phloretin was noticeably more pronounced than that of the conventional [inflammatory bowel disease] drug 5-aminosalicylic acid."
(J.-H. Lee, S.C. Regmi, J.-A. Kim, M.H. Cho, H. Yun, C.-S. Lee, and J. Lee, 2011. Apple flavonoid phloretin inhibits Escherichia coli O157:H7 biofilm formation and ameliorates colon inflammation in rats. Infect. Immun. 79:4819-4827.
Wednesday, December 14, 2011
The holidays are upon us and, for many Americans that means some degree of weight gain and the subsequent New Year’s resolution to diet.
However, shedding the pounds may have some negative consequences on the overall health of older women if the weight loss is not maintained, according to a new study by researchers at Wake Forest Baptist Medical Center.
Published recently in the American Journal of Clinical Nutrition, the study showed that some older women who lose weight gain a lot of their weight back within a year. Importantly, the weight regained is mostly in the form of fat, rather than muscle.
“The body composition of some of the women was worse than before their weight loss,” said Barbara Nicklas, Ph.D., a gerontologist at the J. Paul Sticht Center on Aging and Rehabilitation at Wake Forest Baptist and principal investigator for the study. “When older women lose weight, they also lose lean mass. Most women will gain a lot of the weight back, but the majority of the weight regained is fat.”
For the study, sponsored by the National Institute on Aging, Nicklas and colleagues evaluated 78 postmenopausal women averaging 58 years old, one year after they had intentionally lost an average of 12 percent of their body weight by dieting for another study. The women’s body composition – including change in body weight, muscle and fat – was recorded immediately before and after initial weight loss, then six and 12 months later. There was no weight loss intervention during the year after initial weight loss.
The objective of the study was to determine whether the composition of body weight regained after intentional weight loss is similar to the composition of body weight lost.
At the end of the study, 53 of 78 (68 percent) women at the six-month follow-up and 52 of 68 (76 percent) women at the 12-month follow-up had regained some of their lost weight. Eleven women (16 percent) weighed more at the 12-month follow-up than they did at baseline, and 16 (24 percent) women continued losing weight after the intervention.
A large majority – 75 percent – of those who regained weight gained more than 4.4 pounds at the six-month follow-up, and this number increased to 84 percent at the 12-month follow-up. This subgroup of “regainers” was subsequently used to examine whether lost lean mass from intentional weight loss was recovered during weight regain.
In these participants, researchers found that fat mass was increasing to a greater degree than was lean mass during the postintervention period.
Of the weight lost during the intervention, 67 percent was fat and 33 percent was muscle. Of the weight regained during the entire 12 months of follow-up, 81 percent was fat and 19 percent was muscle. On average, by 12 months after the intervention, 26 percent of fat lost was regained, whereas only six percent of muscle lost was regained.
“Most people will regain their weight after they lose it.” Nicklas said. “Young people tend to regain weight in the proportion that they lost it. But the older women in our study did not appear to be regaining the muscle that they lost during initial weight loss in the same way.”
The long term consequences of losing muscle mass in middle aged and older women is yet unknown, but in combination with the loss in bone density known to occur as we age, the loss of muscle could increase their fall risk, among other things.
“There are certainly a lot of health benefits to weight loss, if you can keep the weight off,” Nicklas said. “For older women who lose weight, however, it is particularly important that they keep the weight off and continue to eat protein and stay physically active so that, if the weight does come back, it will be regained as muscle instead of fat.”
She cautioned that the results from this study were limited to sedentary, abdominally obese, postmenopausal women, and the findings may differ in men or in younger populations. Future studies of weight cycling are needed to determine its effects on muscle strength, quality, and function and body composition in older adults after all weight lost is regained, she said.
“Many health complications associated with overweight and obesity are improved with weight loss,” the researchers wrote. “However, negative consequences (such as loss of muscle mass and bone density) are also associated with weight loss and are detrimental for older adults, which results in a reluctance to recommend intentional weight loss in this population…Because lean mass loss in older adults may be associated with the development of adverse health events and disability, it is important to examine whether the benefits of weight loss outweigh the risks in this population.”
It has been well established that certain lifestyle habits relate to the risk of certain cancers (e.g., smoking and lung cancer). In a well-done analysis, the authors estimate the proportion of cancer in the population associated with a variety of lifestyle and environmental factors.
"Tobacco smoking is by far the most important risk factor for cancer in the UK, responsible for 60 000 cases (19.4% of all new cancer cases) in 2010. The relative importance of other exposures differs by sex. In men, deficient intake of fruits and vegetables (6.1%), occupational exposures (4.9%) and alcohol consumption (4.6%) are next in importance, while in women, it is overweight and obesity (because of the effect on breast cancer) – responsible for 6.9% of cancers, followed by infectious agents (3.7%)."
Forum reviewers considered this to be a well-done paper that used epidemiologic methods that are preferable to those used in some previous such analyses. Generally, they disagreed with the authors that no alcohol consumption was the theoretical "optimum exposure level," as the risk of certain cancers seems to increase primarily from heavy drinking. Further, they found reason to believe that the purported effects related to diet may have been over-estimated.
Nevertheless, this paper provides considerable new information on lifestyle and environmental factors that may relate to the risk of cancer. It puts into perspective the importance of targeting certain behaviours for the potential reduction in the risk of cancer.
In a new study, NYU Langone Medical Center researchers have discovered how cholesterol-lowering drugs called statins promote the breakdown of plaque in the arteries. The study was published online by the journal PLoS One on December 6, 2011.
The findings support a large clinical study that recently showed patients taking high-doses of the cholesterol-lowering medications not only reduced their cholesterol levels but also reduced the amount of plaque in their arteries. However, until now researchers did not fully understand how statins could reduce atherosclerosis, the accumulation of fat and cholesterol that hardens into plaque in arteries, a major cause of mortality in Western countries. High blood cholesterol is a major culprit in atherosclerosis. As a result of narrowing arteries, blood clots can form or plaque can break off causing blockages in vessels. This can lead to a potentially fatal heart attack or stroke.
"Our new research shows statins actually promote the regression of atherosclerosis by altering the expression of a specific cell surface receptor within plaque cells," said co-author of the study, Edward Fisher, MD, PhD, Leon H. Charney Professor of Cardiovascular Medicine and director of the Marc and Ruti Bell Vascular Biology Program at NYU Langone Medical Center. "This molecular phenomenon helps dissolve plaque by expelling coronary artery disease-causing cells from the plaque lining the arteries."
The NYU Langone study reveals how statins promote the transformation of arterial plaques by activating a protein that sits on the surface of macrophages, immune cells that are prevalent in plaque. The immune system sends macrophages to clean up cholesterol deposits in arteries, but once they fill up with the bad form of cholesterol they get stuck in the arteries, triggering the body's inflammatory response. The bloated macrophages then become major components of plaque lining artery walls.
In the study, researchers show in mouse models that statins activate the cell surface protein receptor C-C chemokine receptor type 7 (CCR7), which in turn activates a cell-signaling pathway forcing macrophages out of plaque. In addition, the researchers show that macrophages only leave plaque when CCR7 is expressed. Therefore, regression of plaque is dependent on CCR7, the researchers concluded. The statins appeared to directly regulate and enhance CCR7 gene expression and induce macrophage cells to leave the plaque. CCR7 is a widely studied protein associated with the migration of immune cells and its expression is a marker of the presence of macrophages.
Statins are potent inhibitors of HMG-CoA reductase, the enzyme that plays a central role in the production of cholesterol. Statins have been shown to reduce the risk of cardiovascular disease and cardiac events like heart attack. Cholesterol is needed for all proper cellular function. High-density lipoprotein cholesterol (HDL-C), good cholesterol, helps reduce the risk of atherosclerosis by taking cholesterol away from cells. Low density lipoprotein (LDL-C), bad cholesterol, carries cholesterol to cells. However, an LDL overload in the body increases a person's risk of cardiovascular disease including atherosclerosis.
"Our experimental findings indicate that statins, in addition to lowering LDL cholesterol, have clinical benefits of accelerating plaque regression by a newly discovered mechanism," said co-author Michael Garabedian, PhD, Professor, Department of Microbiology and Urology at NYU Langone Medical Center. "It's possible that these drugs could possibly be more beneficial to a wider population of patients potentially reducing the overall lifetime burden of plaque and the prevention of atherosclerosis."
The two main ways to prevent and control influenza today are annual immunization and antiviral drugs. A team of investigators has found that statins, cholesterol-lowering drugs, may offer an additional treatment to complement these approaches and reduce mortality among patients hospitalized with influenza. The findings are published in The Journal of Infectious Diseases and are now available online.
In an observational study led by Meredith L. Vandermeer, MPH, then with the Oregon Public Health Division in Portland, researchers used data for hospitalized adults during the 2007-2008 influenza season to evaluate the association between patients prescribed statins and influenza-related deaths. The data were drawn from the Centers for Disease Control and Prevention's Emerging Infections Program, which conducts active surveillance for patients hospitalized with confirmed influenza in 59 counties in 10 states.
Among 3,043 hospitalized patients with laboratory-confirmed influenza, 33 percent were given statin medications prior to or during hospitalization. After adjusting for various factors, patients not receiving statins were almost twice as likely to die from influenza as those who did receive the medication.
"Our study found that statins were associated with a decrease in odds of dying among cases hospitalized with laboratory-confirmed influenza, when adjusted for age, race, cardiovascular disease, chronic lung disease, renal disease, influenza vaccine receipt, and initiation of antivirals within 48 hours of admission," the study authors wrote.
Because the study was observational, the authors noted there may have been confounding factors that were not found through the review of patients' charts. Researchers also did not attempt to track the amount of statin use by patients during their entire hospital stay. Randomized controlled trials would best address the potential benefits of statins for influenza treatment, the researchers concluded, and "would allow for examination of such issues as dose response, use in younger age groups, and identifying the most effective class of statins."
In an accompanying editorial, Edward E. Walsh, MD, of the Infectious Diseases Division at Rochester General Hospital in Rochester, N.Y., noted that there have been previous observational studies suggesting statins may reduce mortality from influenza and pneumonia. "One of the important strengths of the current study," Dr. Walsh added, "is that only patients with laboratory-confirmed influenza were included in the analysis," avoiding the uncertainty of disease misclassification possible in other methods.
"Caffeine is the most dynamic and broad-ranging ergogenic aid that I know of. That is, there are aids that could specifically help strength or specifically help long-term endurance, whereas caffeine affects activities that are as short as a minute or as long as several hours; these activities could be aerobic or anaerobic in nature and so on. From that point of view, caffeine is a more general compound that can be used to enhance performance or endurance than any other aid that I could name. There is no question that it is a very potent ergogenic aid."
While many consumers equal 'natural' with 'safe', botanicals and botanical preparations such as plant-based food supplements may contain compounds, like the so called alkenylbenzenes, that are of concern for human health. At high doses these chemical compounds can cause liver cancer in experimental animals. A new study, published in the last issue of the journal Food and Nutrition Sciences, reveals that in many plant-based food supplements levels of these compounds are so low that they are of no concern. Although there are also plant-based food supplements on the market that contain alkenylbenzenes at levels comparable to those causing tumours in laboratory animals. This indicates a need for better regulation and quality control of plant-based food supplements containing alkenylbenzenes.
Botanicals and botanical preparations such as plant-based food supplements are extensively used by consumers within the European Union and the market volume for these products is expanding. In order to assess the safety of plant-based food supplements used in the European Union, an extensive selection and analysis of botanical compounds of concern and present in plant-based food supplements was performed by researchers of Wageningen University, part of Wageningen UR, the University of Milan (Università degli Studi di Milano) and Proform SA collaborating under the EU project PlantLIBRA.
The researchers selected thirty botanical compounds that are of possible concern for human health because they are able to damage the genetic material and/or are carcinogenic. The majority of these compounds were found to belong to the group of the alkenylbenzenes or the group of pyrrolizidine alkaloids. For these botanical ingredients regulatory authorities are aware of the possible risk for human health and consequently the use of pyrrolizidine alkaloid-containing botanicals in food and plant-based food supplements is prohibited in most EU Member States for precautionary health protection reasons. The use of the alkenylbenzenes estragole, methyleugenol, safrole or β-asarone as flavouring agents in food is also banned within the EU. However, restrictions have not (yet) been made with regard to the presence of alkenylbenzenes in plant-based food supplements.
The analysis of several plant-based food supplements containing as main ingredient basil, fennel, nutmeg, sassafras, cinnamon or calamus or their essential oils revealed that some of these products contain relatively high levels of alkenylbenzenes. The researchers concluded that the use of such plant-based food supplements raises a concern for human health and might be of high priority for risk management actions to be taken.
The research team passes the remark that there are also plant-based food supplements in which the levels of the alkenylbenzenes were so low that they are of no concern. Furthermore, they underline that the results obtained in studies in which liver cancer was observed in experimental animals, are based on experiments in which high concentrations of the pure alkenylbenzenes were given to animals instead of administering the plant-based food supplements as such in combination with normal feed. The results obtained in those studies may present an overestimation of the effects compared to those of the alkenylbenzenes in the presence of other ingredients that can be found in the plant-based food supplements or in the normal food. Due to the presence of such a botanical or food pattern, the toxicity of the alkenylbenzenes might be reduced, diminishing the possible risk for human health.
Future studies will place special focus on this subject. However, for the time being it is concluded that some -- although not all -- plant-based food supplements containing the alkenylbenzenes estragole, methyleugenol, safrole or β-asarone might raise a concern for human health and that this indicates a need for better regulation and quality control of plant-based food supplements containing these alkenylbenzenes.
Monday, December 12, 2011
Mothers with jobs report fewer symptoms of depression, better overall health
Mothers with jobs tend to be healthier and happier than moms who stay at home during their children's infancy and pre-school years, according to a new study published by the American Psychological Association.
Researchers analyzed National Institute for Child Health and Human Development Study of Early Child Care and Youth Development data, beginning in 1991 with interviews of 1,364 mothers shortly after their child's birth and including subsequent interviews and observations spanning more than 10 years. The findings were published in the December issue of APA's Journal of Family Psychology.
"In all cases with significant differences in maternal well-being, such as conflict between work and family or parenting, the comparison favored part-time work over full-time or not working," said lead author Cheryl Buehler, PhD, professor of human development and family studies, at the University of North Carolina at Greensboro. "However, in many cases the well-being of moms working part time was no different from moms working full time."
For example, mothers employed part time reported better overall health and fewer symptoms of depression than stay-at-home moms, while there were no reported differences in general health or depressive symptoms between moms employed part time and those who worked full time, the study said.
The part-time and full-time working moms also showed no significant differences when it came to the women's perception that their employment supported family life, including their ability to be a better parent, the authors wrote.
The analysis found that mothers employed part time were just as involved in their child's school as stay-at-home moms, and more involved than moms who worked full time. In addition, mothers working part time appeared more sensitive with their pre-school children and they provided more learning opportunities for toddlers than stay-at-home moms and moms working full time.
Particularly in tough economic times, employers looking for cost savings hire part-time employees because they typically do not receive the same level of benefits, such as health insurance, training and career advancement, the authors pointed out.
"Since part-time work seems to contribute to the strength and well-being of families, it would be beneficial to employers if they provide fringe benefits, at least proportionally, to part-time employees as well as offer them career ladders through training and promotion," said study co-author Marion O'Brien, PhD, professor of human development and family studies, also of the University of North Carolina at Greensboro.
Mothers who participated in the study were from 10 locations across the U.S., and included 24 percent ethnic minorities, 1 percent without a high school degree, and 14 percent single parents. The number of mothers employed part time was fairly consistent at about 25 percent of the total over the span of the study, although mothers moved in and out of part-time work. Part-time employment was defined as between one and 32 hours per week.
The study's limitations included the fact that only one child in the family was included and its exclusive focus on work hours, according to the authors. They recommended that future research include other employment-related factors such as professional status, scheduling flexibility, work commitment and shift schedules.
Friday, December 9, 2011
Vitamin D deficiency is higher among certain demographic segments, including women, the elderly, and the obese. All three groups also share an increased risk of pelvic floor problems, including urinary incontinence. Could there be a connection? Perhaps so, according to recent research.
A study published in Obstetrics & Gynecology compared vitamin D levels with incidence of various forms of pelvic floor disorder among 1,881 women, average age 48. Those with low levels of vitamin D (characterized as less than 30 nanograms per milliliter, or ng/ml) had a 170% increased risk of urinary incontinence, compared to those with higher blood levels.
Why might this be? As a hormone, vitamin D supports a myriad of bodily functions, including maintenance of muscle and bone. As a result, deficiency could undermine the muscular infrastructure of the pelvis needed for urinary control.
Related research suggests that losing weight could result in as much as a 47% decrease in episodes of incontinence, perhaps by reducing the pressure that excess adipose tissue places on the pelvis -- and by increasing levels of vitamin D: Maintaining levels of vitamin D may lower your risk of other ailments, including fractures, tooth loss, depression, chronic pain, and even certain cancers.
Thursday, December 8, 2011
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."
The article is "Fruit and vegetable consumption and the risk of proximal colon, distal colon and rectal cancers in a case-control study in Western Australia" by Neeltje Annema, Jane S. Heyworth, Sarah A. McNaughton, Barry Iacopetta, and Lin Fritschi. It appears in the Journal of the American Dietetic Association, Volume 111, Issue 10 (October 2011) published by Elsevier.
Wednesday, December 7, 2011
Waking later and being active later put people at greater risk of dementia
2. I like to think of my workplace as flexible:
A flexible workplace initiative improved employees' health behavior and well-being, including a rise in the amount and quality of sleep and better health management
3. This is really good news to me:
Physical Fitness Trumps Body Weight in Reducing Death Risks
4. I don't eat a whole lot of eggs, dairy, meat or soy. I'm still not worried about the quality of my protein:
Eggs, dairy and meat proteins have a score of 1.0. Soy protein is the only widely available high-quality plant-based protein that achieves this score.
5. I do eat a lot of fish (and take omega -3 supplements), fruits, vegetables, and whole grains, but no sugary drinks. I really think these apply to everyone, and if so they are good news for me as well:
In the first population-based study in women of childbearing age, those who rarely or never ate fish had 50 percent more cardiovascular problems over eight years than those who ate fish regularly. Compared to women who ate fish high in omega-3 weekly, the risk was 90 percent higher for those who rarely or never ate fish.
Eating fish reduces risk of Alzheimer's disease
Vegetables, fruits, grains reduce stroke risk in women
Study Affirms ‘Mediterranean Diet’ Improves Heart Health
Drinking two or more sugar-sweetened beverages a day may expand a woman's waistline and increase her risk of heart disease and diabetes.
6. Finally proof that I've been right to avoid this:
Snow shoveling increases heart attack risk
7. I only head a well-struck ball if I have a chance to score a goal:
Frequent 'heading' in soccer can lead to brain injury and cognitive impairment
8. Reports of BPA in canned food are disturbing to me - I lived on canned food almost exclusively for 3 years in law school, and canned soups were my daily lunch a few years ago. I continue a lifelong habit of canned vegetables as well:
Consuming canned soup linked to greatly elevated levels of the chemical BPA
Pending federal legislation authored by Rep. Ed Markey, D-Mass., that would ban BPA from all food and beverage containers including canned foods.
9. More good news about coffee - will I eventually succumb and start drinking it?
Coffee may protect against endometrial cancer
10. I'm in no danger of low salt intake as far as I know - if anything. it's probably still to high:
Low salt intake as bad as high
11. I've been taking L-arginine for the reasons enumerated here, and see no reason to stop:
L-arginine: fit, young, athletic men - no advantage
12. I still will emphasize red wine consumption over beer, even though I far prefer beer, but this is encouraging be to diversify a little more:
Beer could stand up alongside wine regarding positive effects on cardiovascular health.
13. Starting in January I won't have a Tuesday night soccer game any more and I haven't figured out how to replace the exercise that I know is crucial to my health (no, I won't go to a gym or jog!):
150 minutes of moderate to vigorous activity a week, which is the national guideline, provided a 65 percent improvement in sleep quality. People also said they felt less sleepy during the day, compared to those with less physical activity.
Exercise helps us to eat a healthy diet
Aerobic Fitness May Reduce Brain Aging
Mediterranean Diet and Exercise Can Reduce Sleep Apnea Symptoms
Tuesday, December 6, 2011
Waking later and being active later put people at greater risk of dementia
Older women with weaker circadian rhythms, who are less physically active or are more active later in the day are more likely to develop dementia or mild cognitive impairment than women who have a more robust circadian rhythm or are more physically active earlier in the day. That’s the finding of a new study in the latest issue of the Annals of Neurology.
“We’ve known for some time that circadian rhythms, what people often refer to as the “body clock”, can have an impact on our brain and our ability to function normally,” says Greg Tranah, PhD., a scientist at the California Pacific Medical Center Research Institute – part of the Sutter Health network – and the lead author of the study. “What our findings suggest is that future interventions such as increased physical activity or using light exposure interventions to influence circadian rhythms, could help influence cognitive outcomes in older women.”
The researchers collected data on activity and circadian rhythm from 1,282 healthy women, all over the age of 75, who were taking part in the Study of Osteoporotic Fractures. All the women underwent a series of neuropsychological tests to ensure they had no evidence of cognitive or brain problems. At the end of five years 15 percent of the women had developed dementia and 24 percent had some form of mild cognitive impairment (MCI). Those women who had weaker circadian rhythm activity, lower levels of activity, or whose peak level of activity was later in the day, were at highest risk of developing dementia or MCI.
“This was not a small difference, but a rather sizable, statistically significant one,” says Tranah. “Those who had the later wake times, whose activity was later in the day, were 80 percent more likely to develop MCI or dementia compared to women who had earlier wake times and earlier activity.”
Circadian rhythms play an important role in the control of sleep-wake cycles and there is considerable evidence to show they also play a role in regulating certain brain functions, such as alertness, learning and memory. As people get older the activity level of those rhythms – how strong they are - often change, bringing with it changes in sleep patterns and levels of physical activity.
“To our knowledge this is the first study to show such a strong connection between circadian activity rhythm and the subsequent development of dementia or MCI,” says Tranah. “The reasons why this is so are not yet clear. The changes in circadian rhythm may directly influence the onset of dementia or MCI, or the decrease in activity may be a consequence, a warning sign if you like, that changes are already taking place in the brain. Identifying what the reason is could help us develop therapies to delay, or slow down, the development of brain problems in the elderly.”
In an accompanying commentary in the journal, Andrew Lim and Clifford Saper of the Department of Neurology at Harvard Medical School, say the study “represents a significant advance” in understanding the connection between circadian rhythm activity and dementia. “By showing that variations in rest-activity patterns precede the development of cognitive impairment and dementia, Tranah and colleagues have identified both a novel predictor of and a potential therapeutic target for incident cognitive deterioration and dementia.”
A flexible workplace initiative improved employees' health behavior and well-being, including a rise in the amount and quality of sleep and better health management, according to a new study by University of Minnesota sociology professors Erin Kelly and Phyllis Moen, which appears in the December issue of the Journal of Health and Social Behavior.
"Our study shows that moving from viewing time at the office as a sign of productivity, to emphasizing actual results can create a work environment that fosters healthy behavior and well-being," says Moen. "This has important policy implications, suggesting that initiatives creating broad access to time flexibility encourage employees to take better care of themselves."
Using longitudinal data collected from 608 employees of a white-collar organization before and after a flexible workplace initiative was implemented, the study examined changes in health-promoting behaviors and health outcomes among the employees participating in the initiative compared to those who did not participate.
Introduced at the Best Buy headquarters in Richfield, Minn. in 2005, the workplace initiative—dubbed the Results Only Work Environment (ROWE)—redirected the focus of employees and managers towards measurable results and away from when and where work is completed. Under ROWE, employees were allowed to routinely change when and where they worked based on their individual needs and job responsibilities without seeking permission from a manager or even notifying one.
- Employees participating in the flexible workplace initiative reported getting almost an extra hour (52 minutes) of sleep on nights before work.
- Employees participating in the flexible workplace initiative managed their health differently: They were less likely to feel obligated to work when sick and more likely to go to a doctor when necessary, even when busy.
- The flexible workplace initiative increased employees' sense of schedule control and reduced their work-family conflict which, in turn, improved their sleep quality, energy levels, self-reported health, and sense of personal mastery while decreasing employees' emotional exhaustion and psychological distress.
The importance of protein in the human body is undeniable. However, the idea of what makes a protein a "quality protein" has not been as easy to determine. A new study from the Journal of Agriculture and Food Chemistry takes a closer look at the criteria for determining the quality of a protein.
Traditional methods for determining protein quality have shown animal proteins such as milk and eggs to be high in quality. However, those who are interested in a plant-based diet, or diversifying their proteins, have a more difficult time determining which of their choices are high in quality. Testing methods have shown most plant proteins, such as pea protein, are lower in quality than animal-based proteins.
"Accurate methods for determining protein quality are key to helping people plan a healthful diet," said Glenna Hughes, MS, research scientist at Solae. "Due to the increasing interest in including plant-based proteins in the diet, accurate information on protein quality is needed in scientific literature to help educate consumers and healthcare professionals on this topic."
The Food and Agriculture Organization (FAO) and the World Health Organization (WHO) recommend using the protein digestibility-corrected amino acid score (PDCAAS) as a simple and scientific procedure for assessing protein quality. The PDCAAS methodology focuses on three different parameters: the amount of each essential amino acid the protein contains, how easily the protein can be digested, and by taking both of those parameters into account, whether the protein meets the FAO/WHO's amino acid requirements set for children aged two to five years, as they have higher needs to support growth and development than adults.
According to this study, soy protein has a PDCAAS of 1.00, meaning it is a high-quality protein that meets the needs of both children and adults. Eggs, dairy and meat proteins also have a PDCAAS score of 1.0.
However, soy protein is the only widely available high-quality plant-based protein that achieves this score.
"It's important for people to understand that a plant-based diet is healthy, but that not all proteins are created equal," said Connie Diekman, RD, LD, FADA. "If you are planning a vegetarian diet or want to incorporate plant-based proteins in your diet, understanding protein quality using the PDCAAS scale can allow you to select proteins that score higher, such as soy, to ensure that you are getting the essential amino acids you need."
If you maintain or improve your fitness level -- even if your body weight has not changed or increased -- you can reduce your risk of death, according to research reported in Circulation: Journal of the American Heart Association.
In a study of 14,345 adult men, mostly white and middle or upper class, researchers found that:
* Maintaining or improving fitness was associated with a lower death risk even after controlling for Body Mass Index (BMI) change.
* Every unit of increased fitness (measured as MET, metabolic equivalent of task) over six years was associated with a 19 percent lower risk of heart disease and stroke-related deaths and a 15 percent lower risk of death from any cause.
* Becoming less fit was linked to higher death risk, regardless of BMI changes.
* BMI change was not associated with death risks.
BMI is a measurement based on weight and height (kg/m2). MET measures the intensity of aerobic exercise -- specifically, the ratio of metabolic rate during a specific physical activity to a reference rate of metabolic rate at rest.
"This is good news for people who are physically active but can't seem to lose weight," said Duck-chul Lee, Ph.D., the study's lead researcher and physical activity epidemiologist in the Department of Exercise Science at the University of South Carolina's Arnold School of Public Health in Columbia. "You can worry less about your weight as long as you continue to maintain or increase your fitness levels."
Results of the study underscore the importance of physical inactivity as a risk factor for death from heart disease and stroke, said researchers. Researchers also found no association between changes in body fat percentage or body weight and death risk.
Participants, who were an average 44 years old, were part of the long-term, large-scale Aerobics Center Longitudinal Study. They underwent at least two comprehensive medical exams.
Researchers used maximal treadmill tests to estimate physical fitness (maximal METs), and height and weight measurements to calculate BMI. They recorded changes in BMI and physical fitness over six years.
After more than 11 years of follow-up, researchers determined the relative risks of dying among men who lost, maintained or gained fitness over six years. They accounted for other factors that can affect outcomes, including BMI change, age, family history of heart disease, beginning fitness level, changes in lifestyle factors such as smoking and physical activity, and medical conditions such as high blood pressure or diabetes.
One possible explanation for these results: about 90 percent of the men were either normal weight or overweight at the beginning of the study. Among obese people, changes in BMI might have a significant effect on death risks. So it's unclear whether these results would apply to severely obese people, Lee said.
A BMI score under 25 is considered healthy, 25 to less than 30 is overweight, and 30 or greater is obese.
Because the study was mostly done in white middle and upper class men, it's difficult to know whether the results apply to other racial and socioeconomic groups. Women would likely have similar results as the men in the study, Lee said.
Young women may reduce their risk of developing cardiovascular disease simply by eating more fish rich in omega-3 fatty acids, researchers reported in Hypertension: Journal of the American Heart Association.
In the first population-based study in women of childbearing age, those who rarely or never ate fish had 50 percent more cardiovascular problems over eight years than those who ate fish regularly. Compared to women who ate fish high in omega-3 weekly, the risk was 90 percent higher for those who rarely or never ate fish.
Researchers used a Danish nationwide population based pregnancy cohort to examine whether or not eating more fish might reduce cardiovascular disease risk in the young women.
About 49,000 women, 15-49 years old, median age of just under 30 years in early pregnancy -- were interviewed by telephone or answered food frequency questionnaires about how much, what types and how often they ate fish, as well as lifestyle and family history questions.
Researchers recorded 577 cardiovascular events during the eight-year period, including five cardiovascular deaths in women without any prior diagnosis of the disease. In all, 328 events were due to hypertensive disease, 146 from cerebrovascular disease, and 103 from ischemic heart disease.
Inpatient and outpatient admission for cardiovascular disease was much more common among women who reported eating little or no fish. In three different assessments over a 30-week period, women who never ate fish had a three-fold higher disease risk compared to women who ate fish every week.
"To our knowledge this is the first study of this size to focus exclusively on women of childbearing age," said Marin Strøm, Ph.D., lead researcher and post doctoral fellow at the Centre for Fetal Programming, at Statens Serum Institut in Copenhagen, Denmark. "The biggest challenge in getting health messages like this across to younger populations is that usually the benefits may not be evident for 30 or 40 years, but our study shows this is not the case. We saw a strong association with cardiovascular disease in the women who were still in their late 30's."
Fish oil contains long chain omega-3 polyunsaturated fatty acids, which are believed to protect against heart and vascular disease. Few women in the study took fish oil supplements, so these were excluded from the analyses and the results were based on the dietary intake of omega-3 fatty acids, not intake from supplements.
Most previous studies that found cardiovascular benefits of omega-3 fatty acids have focused on men, according to Strøm.
"Men and women share many cardiovascular risk factors, but some studies have shown that there might also be gender differences. For example, inflammation, cholesterol, and triglyceride levels may have a more negative influence among women," Strom said.
Even women who ate fish only a couple of times a month benefitted. "Women who eat fish should find the results encouraging, but it is important to emphasize that to obtain the greatest benefit from fish and fish oils, women should follow the dietary recommendations to eat fish as a main meal at least twice a week," she said.
The most common fish consumed by women in the study were cod, salmon, herring, and mackerel.
"Our study shows that for younger women, eating fish is very important for overall health, and even though we found cardio-protective effects at relatively modest dietary levels, higher levels may yield additional benefits," Strøm said.
Urban legend warns shoveling snow causes heart attacks, and the legend seems all too accurate, especially for male wintery excavators with a family history of premature cardiovascular disease. However, until recently this warning was based on anecdotal reports.
Two of the most important cardiology associations in the US include snow -shoveling on their websites as a high risk physical activity, but all the citation references indicate that this warning was based one or two incidents.
"We thought that this evidence should not be enough to convince us that snow -shoveling is potentially dangerous, " says Adrian Baranchuk, a professor in Queen's School of Medicine and a cardiologist at Kingston General Hospital.
Dr. Baranchuk and his team retrospectively reviewed KGH patient records from the two previous winter seasons and discovered that of the 500 patients who came to the hospital with heart problems during this period, 7 per cent (35 patients) had started experiencing symptoms while shoveling snow.
"That is a huge number," says Dr. Baranchuk. "7 per cent of anything in medicine is a significant proportion. Also, if we take into account that we may have missed some patients who did not mention that they were shoveling snow around the time that the episode occurred, that number could easily double."
The team also identified three main factors that put individuals at a high risk when shoveling snow. The number one factor was gender (31 of the 35 patients were male), the second was a family history of premature coronary artery disease (20 of the 35 patients), and the third was smoking (16 out of 35 patients). The second two factors may carry much more weight than the first, however, since the team could not correct for high rate of snow shoveling among men in their sample.
A history of regularly taking four or more cardiac medications was found to be preventative.
Friday, December 2, 2011
Thursday, December 1, 2011
Swedish women who ate an antioxidant-rich diet had fewer strokes regardless of whether they had a previous history of cardiovascular disease, in a study reported in Stroke: Journal of the American Heart Association.
"Eating antioxidant-rich foods may reduce your risk of stroke by inhibiting oxidative stress and inflammation," said Susanne Rautiainen, M.Sc., the study's first author and Ph.D. student at the Karolinska Institutet in Sweden. "This means people should eat more foods such as fruits and vegetables that contribute to total antioxidant capacity."
Oxidative stress is an imbalance between the production of cell-damaging free radicals and the body's ability to neutralize them. It leads to inflammation, blood vessel damage and stiffening.
Antioxidants such as vitamins C and E, carotenoids and flavonoids can inhibit oxidative stress and inflammation by scavenging the free radicals. Antioxidants, especially flavonoids, may also help improve endothelial function and reduce blood clotting, blood pressure and inflammation.
"In this study, we took into account all the antioxidants present in the diet, including thousands of compounds, in doses obtained from a usual diet," Rautiainen said. Researchers collected dietary data through a food-frequency questionnaire. They used a standard database to determine participants' total antioxidant capacity (TAC), which measures the free radical reducing capacity of all antioxidants in the diet and considers synergistic effects between substances.
Researchers categorized the women according to their TAC levels — five groups without a history of cardiovascular disease and four with previous cardiovascular disease.
For women with no history of cardiovascular disease who had the highest TAC, fruits and vegetables contributed about 50 percent of TAC. Other contributors were whole grains (18 percent), tea (16 percent) and chocolate (5 percent).
The study found:
Higher TAC was related to lower stroke rates in women without cardiovascular disease.
Women without cardiovascular disease with the highest levels of dietary TAC had a statistically significant 17 percent lower risk of total stroke compared to those in the lowest quintile.
Women with history of cardiovascular disease in the highest three quartiles of dietary TAC had a statistically significant 46 percent to 57 percent lower risk of hemorrhagic stroke compared with those in the lowest quartile.
"Women with a high antioxidant intake may be more health conscious and have the sort of healthy behaviors that may have influenced our results," Rautiainen said. "However, the observed inverse association between dietary TAC and stroke persisted after adjustments for potential confounders related to healthy behavior such as smoking, physical activity and education."
For the study, researchers used the Swedish Mammography Cohort to identify 31,035 heart disease-free women and 5,680 women with a history of heart disease in two counties. The women were 49-83 years old.
Researchers tracked the cardiovascular disease-free women an average 11.5 years and the women with cardiovascular disease 9.6 years, from September 1997 through the date of first stroke, death or Dec. 31, 2009, whichever came first.
Researchers identified 1,322 strokes among cardiovascular disease-free women and 1,007 strokes among women with a history of cardiovascular disease from the Swedish Hospital Discharge Registry.
"To the best of our knowledge, no study has assessed the relation between dietary TAC and stroke risk in participants with a previous history of cardiovascular disease," Rautiainen said. "Further studies are needed to assess the link between dietary TAC and stroke risk in men and in people in other countries, but we think our results are applicable."
Wednesday, November 30, 2011
People who eat baked or broiled fish on a weekly basis may be improving their brain health and reducing their risk of developing mild cognitive impairment (MCI) and Alzheimer's disease, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA).
"This is the first study to establish a direct relationship between fish consumption, brain structure and Alzheimer's risk," said Cyrus Raji, M.D., Ph.D., from the University of Pittsburgh Medical Center and the University of Pittsburgh School of Medicine. "The results showed that people who consumed baked or broiled fish at least one time per week had better preservation of gray matter volume on MRI in brain areas at risk for Alzheimer's disease."
Alzheimer's disease is an incurable, progressive brain disease that slowly destroys memory and cognitive skills. According to the National Institute on Aging, as many as 5.1 million Americans may have Alzheimer's disease. In MCI, memory loss is present but to a lesser extent than in Alzheimer's disease. People with MCI often go on to develop Alzheimer's disease.
For the study, 260 cognitively normal individuals were selected from the Cardiovascular Health Study. Information on fish consumption was gathered using the National Cancer Institute Food Frequency Questionnaire. There were 163 patients who consumed fish on a weekly basis, and the majority ate fish one to four times per week. Each patient underwent 3-D volumetric MRI of the brain. Voxel-based morphometry, a brain mapping technique that measures gray matter volume, was used to model the relationship between weekly fish consumption at baseline and brain structure 10 years later. The data were then analyzed to determine if gray matter volume preservation associated with fish consumption reduced risk for Alzheimer's disease. The study controlled for age, gender, education, race, obesity, physical activity, and the presence or absence of apolipoprotein E4 (ApoE4), a gene that increases the risk of developing Alzheimer's.
Gray matter volume is crucial to brain health. When it remains higher, brain health is being maintained. Decreases in gray matter volume indicate that brain cells are shrinking.
The findings showed that consumption of baked or broiled fish on a weekly basis was positively associated with gray matter volumes in several areas of the brain. Greater hippocampal, posterior cingulate and orbital frontal cortex volumes in relation to fish consumption reduced the risk for five-year decline to MCI or Alzheimer's by almost five-fold.
"Consuming baked or broiled fish promotes stronger neurons in the brain's gray matter by making them larger and healthier," Dr. Raji said. "This simple lifestyle choice increases the brain's resistance to Alzheimer's disease and lowers risk for the disorder."
The results also demonstrated increased levels of cognition in people who ate baked or broiled fish.
"Working memory, which allows people to focus on tasks and commit information to short-term memory, is one of the most important cognitive domains," Dr. Raji said. "Working memory is destroyed by Alzheimer's disease. We found higher levels of working memory in people who ate baked or broiled fish on a weekly basis, even when accounting for other factors, such as education, age, gender and physical activity."
Eating fried fish, on the other hand, was not shown to increase brain volume or protect against cognitive decline.
More on Alzheimer's:
According to statistics from the National Institute on Aging, Alzheimer’s disease is the most common form of dementia in older people. Alzheimer’s is a progressive brain disease; it is irreversible and causes a decline in memory and cognitive skills.
Alzheimer’s disease is the seventh leading cause of death in the United States. It is the only cause of death among the top 10 that cannot be prevented, cured or even significantly arrested. Two-thirds of people over the age of 65 who have the disease are women. This is a startling statistic, and one that requires increased attention and research.
“Clearly, this is an illness of women more than men,” said Victor Henderson, MD, MS, Professor of Epidemiology and Neurology and Neurological Sciences at Stanford University. “In part, it has to do with the fact that women live longer than men. There are real differences in longevity.”
Researchers have long studied the relationship between the hormone estrogen and Alzheimer's disease, but the results have been inconclusive thus far. “There are other risk factors that may come into play,” said Henderson, “which can further explain why women may be predisposed to Alzheimer’s disease.” Some of these factors include: family history, genetics, and some evidence suggests heart disease.
One of the first signs of Alzheimer’s disease may be forgetfulness and difficulty remembering newly learned information. But the disease gradually gets worse. According to the National Alzheimer’s Association in Chicago, other symptoms develop over time and may include:
• Challenges in planning or problem solving.
• Difficulty completing familiar tasks at home, at work, or at leisure.
• Confusion with time or place.
• Trouble understanding visual images and spatial relationships.
• New problems with words in speech or writing.
• Misplacing objects and losing the ability to retrace steps.
• Decreased or poor judgment.
• Withdrawal from work or social activities.
• Changes in mood and personality.
Here's another reason why "an apple a day keeps the doctor away"—according to new research findings published in the Journal of Leukocyte Biology, oral ingestion of apple polyphenols (antioxidants found in apple peels) can suppress T cell activation to prevent colitis in mice. This study is the first to show a role for T cells in polyphenol-mediated protection against an autoimmune disease and could lead to new therapies and treatments for people with disorders related to bowel inflammation, such as ulcerative colitis, Crohn's disease and colitis-associated colorectal cancer.
"Many people with colitis use some form of dietary supplement to complement conventional therapies, but most of the information on the health effects of complementary medicine remains anecdotal. Also, little is known about exactly how these therapies work, if they work at all," said David W. Pascual, Ph.D., a researcher involved in the work from the Department of Immunology and Infectious Diseases at Montana State University in Bozeman, Montana. "Our results show that a natural product found in apple peels can suppress colonic inflammation by antagonizing inflammatory T cells to enhance resistance against autoimmune disease."
To make this discovery, scientists used a chemically induced model of colitis with Dextran sulfate sodium (DSS), researchers administered an oral placebo to one group of mice, and the other group of mice was given an oral dose of apple polyphenols every day during the course of the disease. Results showed that mice treated orally with apple polyphenols were protected from colitis. Importantly, scientists also found that the treated mice had fewer activated T cells in their colons. In mice lacking T cells, apple polyphenols were unable to protect against colitis or suppress proinflammatory cytokine expression, indicating apple polyphenols protect against colitis via the suppression of T cell activation and/or recruitment.
"It appears that the old adage rings true in more ways than one," said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology, "In addition to the obvious health benefits of the nutrients and fiber in fruits and vegetables, this study indicates that even something as relatively common as the apple contains other healthy ingredients that can have serious therapeutic value."
Tuesday, November 29, 2011
Using advanced imaging techniques and cognitive tests, researchers at Albert Einstein College of Medicine of Yeshiva University and Montefiore Medical Center , the University Hospital and academic medical center for Einstein, have shown that repeatedly heading a soccer ball increases the risk for brain injury and cognitive impairment. The imaging portion of the findings was presented today at the annual meeting of the Radiological Society of North America (RSNA) in Chicago.
The researchers used diffusion tensor imaging (DTI), an advanced MRI-based imaging technique, on 38 amateur soccer players (average age: 30.8 years) who had all played the sport since childhood. They were asked to recall the number of times they headed the ball during the past year. (Heading is when players deliberately hit or field the soccer ball with their head.) Researchers ranked the players based on heading frequency and then compared the brain images of the most frequent headers with those of the remaining players. They found that frequent headers showed brain injury similar to that seen in patients with concussion, also known as mild traumatic brain injury (TBI).
The findings are especially concerning given that soccer is the world's most popular sport with popularity growing in the U.S., especially among children. Of the 18 million Americans who play soccer, 78 percent are under the age of eighteen. Soccer balls are known to travel at speeds as high as 34 miles per hour during recreational play, and more than twice that during professional play.
After confirming the potentially damaging impact of frequent heading, "Our goal was to determine if there is a threshold level for heading frequency that, when surpassed, resulted in detectable brain injury," said lead author Michael Lipton, M.D., Ph.D. , associate director of Einstein's Gruss Magnetic Resonance Research Center and medical director of MRI services at Montefiore. Further analysis revealed a threshold level of approximately 1,000 to 1,500 heads per year. Once players in the study exceeded that number, researchers observed significant injury.
"While heading a ball 1,000 or 1,500 times a year may seem high to those who don't participate in the sport, it only amounts to a few times a day for a regular player," observed Dr. Lipton, who is also associate professor of radiology, of psychiatry and behavioral sciences ), and of the Dominick P. Purpura Department of Neuroscience at Einstein.
"Heading a soccer ball is not an impact of a magnitude that will lacerate nerve fibers in the brain," said Dr. Lipton. "But repetitive heading may set off a cascade of responses that can lead to degeneration of brain cells."
Researchers identified five areas, in the frontal lobe (behind the forehead) and in the temporo-occipital region (the bottom-rear areas) of the brain that were affected by frequent heading – areas that are responsible for attention, memory, executive functioning and higher-order visual functions. In a related study, Dr. Lipton and colleague Molly Zimmerman, Ph.D. , assistant professor in the Saul R. Korey Department of Neurology at Einstein, gave the same 38 amateur soccer players tests designed to assess their neuropsychological function. Players with the highest annual heading frequency performed worse on tests of verbal memory and psychomotor speed (activities that require mind-body coordination, like throwing a ball) relative to their peers.
"These two studies present compelling evidence that brain injury and cognitive impairment can result from heading a soccer ball with high frequency," Dr. Lipton said. "These are findings that should be taken into consideration in planning future research to develop approaches to protect soccer players."
Heading is an essential part of soccer and is unlikely to be eliminated from practice or play.
As there appears to be a safe range for heading frequency, additional research can help refine this number, which can then be used to establish heading guidelines. As in other sports, the frequency of potentially harmful actions in practice and games could be monitored and restricted based on confirmed unsafe exposure thresholds.
"In the past, pitchers in Little League Baseball sustained shoulder injuries at a rate that was alarming," Dr. Lipton noted. "But ongoing research has helped shape various approaches, including limits on the amount of pitching a child performs, which have substantially reduced the incidence of these injuries."
"Brain injury due to heading in children, if we confirm that it occurs, may not show up on our radar because the impairment will not be immediate and can easily be attributed to other causes like ADHD or learning disabilities," continued Dr. Lipton. "We, including the agencies that supervise and encourage soccer play, need to do the further research to precisely define the impact of excessive heading on children and adults in order to develop parameters within which soccer play will be safe over the long term."
Eating a Mediterranean diet combined with physical activity can help to improve some of the symptoms of sleep apnea, according to new research. The study, which is published online in the European Respiratory Journal, looked at the impact a Mediterranean diet can have on obese people with sleep apnea, compared to those on a prudent diet.
Obstructive sleep apnea syndrome (OSAS) causes frequent pauses of breathing to occur during sleep, which disrupts a person's normal sleeping pattern. It is one of the most prevalent sleep-related breathing disorders with approximately 2-4% of the adult population experiencing the condition. This percentage increases up to 20-40% with obesity, and weight loss is often an essential part of the recommended treatment plan.
The researchers, from the University of Crete in Greece, examined 40 obese patients suffering from OSAS. Twenty patients were given a prudent diet to follow, while the other 20 followed a Mediterranean diet. Both groups were also encouraged to increase their physical activity, mainly involving walking for at least 30 minutes each day.
In both groups, the patients also received continuous positive airway pressure (CPAP) therapy which involves wearing a mask that generates an air stream, keeping the upper airway open during sleep.
The researchers monitored the patients during a sleep study, known as polysomnography. This involved monitoring several markers for OSAS, including electrical activity in the brain, eye movements and snoring. The patients were examined at the start of the study and again 6 months later.
The results showed that people following the Mediterranean diet had a reduced number of disturbances, known as apneas, during the rapid eye movement (REM) stage of sleep, which usually accounts for approximately 25% of total sleep during the night.
The findings also revealed that people following the Mediterranean diet also showed a greater adherence to the calorie restricted diet, an increase in physical activity and a greater decrease in abdominal fat.
The results of this small sample did show an improvement during one stage of sleep for people with sleep apnea, however it did not show an overall improvement in severity of the condition. The authors suggest that further studies in a larger sample are required to fully understand the benefits of this diet.
Christopher Papandreou, lead author for the research, said: "This is the first study examining the impact of the Mediterranean diet in combination with physical activity on OSAS via changes in the human body. Our results showed that the number of disturbances during REM sleep was reduced more in the Mediterranean diet group than the other group. Recent reports have related an increase in disturbances during REM sleep with the risk of developing significant systemic consequences like diabetes type II. However, its clinical significance remains unclear. Finally, more studies are needed to examine the effect of the above diet on this sleep-related breathing disorder taking into account its anti-inflammatory and antioxidant properties."