Tuesday, July 30, 2013
Exercise May be the Best Medicine for Alzheimer's
New research out of the University of Maryland School of Public Health shows that exercise may improve cognitive function in those at risk for Alzheimer’s by improving the efficiency of brain activity associated with memory. Memory loss leading to Alzheimer’s disease is one of the greatest fears among older Americans. While some memory loss is normal and to be expected as we age, a diagnosis of mild cognitive impairment, or MCI, signals more substantial memory loss and a greater risk for Alzheimer’s, for which there currently is no cure.
The study, led by Dr. J. Carson Smith, assistant professor in the Department of Kinesiology, provides new hope for those diagnosed with MCI. It is the first to show that an exercise intervention with older adults with mild cognitive impairment (average age 78) improved not only memory recall, but also brain function, as measured by functional neuroimaging (via fMRI). The findings are published in the Journal of Alzheimer’s Disease.
“We found that after 12 weeks of being on a moderate exercise program, study participants improved their neural efficiency – basically they were using fewer neural resources to perform the same memory task,” says Dr. Smith. “No study has shown that a drug can do what we showed is possible with exercise.”
Recommended Daily Activity: Good for the Body, Good for the Brain
Two groups of physically inactive older adults (ranging from 60-88 years old) were put on a 12-week exercise program that focused on regular treadmill walking and was guided by a personal trainer. Both groups – one which included adults with MCI and the other with healthy brain function – improved their cardiovascular fitness by about ten percent at the end of the intervention. More notably, both groups also improved their memory performance and showed enhanced neural efficiency while engaged in memory retrieval tasks.
The good news is that these results were achieved with a dose of exercise consistent with the physical activity recommendations for older adults. These guidelines urge moderate intensity exercise (activity that increases your heart rate and makes you sweat, but isn’t so strenuous that you can’t hold a conversation while doing it) on most days for a weekly total of 150 minutes.
Measuring Exercise’s Impact on Brain Health and Memory
One of the first observable symptoms of Alzheimer’s disease is the inability to remember familiar names. Smith and colleagues had study participants identify famous names and measured their brain activation while engaged in correctly recognizing a name – e.g., Frank Sinatra, or other celebrities well known to adults born in the 1930s and 40s. “The task gives us the ability to see what is going on in the brain when there is a correct memory performance,” Smith explains.
Tests and imaging were performed both before and after the 12-week exercise intervention. Brain scans taken after the exercise intervention showed a significant decrease in the intensity of brain activation in eleven brain regions while participants correctly identified famous names. The brain regions with improved efficiency corresponded to those involved in the pathology of Alzheimer’s disease, including the precuneus region, the temporal lobe, and the parahippocampal gyrus.
The exercise intervention was also effective in improving word recall via a “list learning task,” i.e., when people were read a list of 15 words and asked to remember and repeat as many words as possible on five consecutive attempts, and again after a distraction of being given another list of words.
“People with MCI are on a very sharp decline in their memory function, so being able to improve their recall is a very big step in the right direction,” Smith states.
The results of Smith’s study suggest that exercise may reduce the need for over-activation of the brain to correctly remember something. That is encouraging news for those who are looking for something they can do to help preserve brain function.
Dr. Smith has plans for a larger study that would include more participants, including those who are healthy but have a genetic risk for Alzheimer’s, and follow them for a longer time period with exercise in comparison to other types of treatments. He and his team hope to learn more about the impact of exercise on brain function and whether it could delay the onset or progression of Alzheimer’s disease.
Thursday, July 25, 2013
Green Coffee Beans = Weight Loss
A new review article evaluates if clinical data support the use of green coffee for weight loss. A literature search was conducted that yielded 5 clinical trials and 1 meta-analysis. Studies were evaluated for quality in accordance to clinical practice and US Food and Drug Administration guidelines.
The amount of weight loss ranged from approximately 1 to 8 kg, with the meta-analysis finding a statistically significant difference in body weight, with a mean difference of −2.47 kg between green coffee and placebo (95% confidence interval = −4.23 to −0.72).
The duration of trials varied between 4 and 12 weeks, and the dose of chlorogenic acid varied from 81 to 400 mg.
Tuesday, July 23, 2013
My Health Practics In Question Again
My health practices have been shaken up considerably over the years, but never more so than the last few days.
First came the report that fish oil supplementation seems to increase the risk of prostate cancer, which I discussed here, noting all the benefits of fish oil.
Next came the report that light drinking may not offer health benefits after all. However, I have documented the many apparent benefits of moderate alcohol consumption here, and while this study will make me feel less guilty when I don't have a drink, I will continue moderate drinking for pleasure, and, I still believe, for health benefits.
The latest disturbing study brings into question the cardiovascular health benefits of resveratrol supplements, which I take religiously, and anti-oxidant supplements in general.
And to top it all off, an article in The Atlantic questions the values of supplements as well, particularly anti-oxidants and focuses on the dangers of vitamins A, C, E, and beta-carotene, all of which I did take but quit some time ago.
Monday, July 22, 2013
Resveratrol counteracts exercise benefits in older men
In older men, a natural antioxidant compound found in red grapes and other plants -- called resveratrol -- blocks many of the cardiovascular benefits of exercise, according to research published today [22 July 2013] in The Journal of Physiology.
Resveratrol has received widespread attention as a possible anti-aging compound and is now widely available as a dietary supplement; much has been made of its role in explaining the cardiovascular health benefits of red wine, and other foods. But now, new research at The University of Copenhagen surprisingly suggests that eating a diet rich in antioxidants may actually counteract many of the health benefits of exercise, including reduced blood pressure and cholesterol.
In contrast to earlier studies in animals in which resveratrol improved the cardiovascular benefits of exercise, this study in humans has provided surprising and strong evidence that in older men, resveratrol has the opposite effect.
What is emerging is a new view that antioxidants are not a fix for everything, and that some degree of oxidant stress may be necessary for the body to work correctly. This pivotal study suggests that reactive oxygen species, generally thought of as causing aging and disease, may be a necessary signal that causes healthy adaptations in response to stresses like exercise. So too much of a good thing (like antioxidants in the diet) may actually be detrimental to our health.
Lasse Gliemann, a PhD student who worked on the study at The University of Copenhagen, explains how they conducted the research, and the results they found: "We studied 27 healthy, physically inactive men around 65 years old for 8 weeks. During the 8 weeks all of the men performed high-intensity exercise training and half of the group received 250 mg of resveratrol daily, whereas the other group received a placebo pill (a pill containing no active ingredient). The study design was double-blinded, thus neither the subjects nor the investigators knew which participant that received either resveratrol or placebo.
"We found that exercise training was highly effective in improving cardiovascular health parameters, but resveratrol supplementation attenuated the positive effects of training on several parameters including blood pressure, plasma lipid concentrations and maximal oxygen uptake."
Ylva Hellsten, the leader of the project, says:"We were surprised to find that resveratrol supplementation in aged men blunts the positive effects of exercise training on cardiovascular health parameters, in part because our results contradict findings in animal studies.
"It should be noted that the quantities of resveratrol given in our research study are much higher than what could be obtained by intake of natural foods."
This research adds to the growing body of evidence questioning the positive effects of antioxidant supplementation in humans.
Michael Joyner, from The Mayo Clinic USA, says how the study has wider implications for research: "In addition to the surprising findings on exercise and resveratrol, this study shows the continuing need for mechanistic studies in humans. Too often human studies focus on large scale outcomes and clinical trials and not on understanding the basic biology of how we adapt."
Skipping breakfast may increase coronary heart disease risk
Here's more evidence why breakfast may be the most important meal of the day: Men who reported that they regularly skipped breakfast had a higher risk of a heart attack or fatal coronary heart disease in a study reported in the American Heart Association journal Circulation.
Researchers analyzed food frequency questionnaire data and tracked health outcomes for 16 years (1992-2008) on 26,902 male health professionals ages 45-82. They found:
Men who reported they skipped breakfast had a 27 percent higher risk of heart attack or death from coronary heart disease than those who reported they didn't.
The men who reported not eating breakfast were younger than those who did, and were more likely to be smokers, employed full time, unmarried, less physically active and drank more alcohol.
Men who reported eating late at night (eating after going to bed) had a 55 percent higher coronary heart disease risk than those who didn't. But researchers were less convinced this was a major public health concern because few men in the study reported this behavior.
During the study, 1,572 of the men had first-time cardiac events.
"Skipping breakfast may lead to one or more risk factors, including obesity, high blood pressure, high cholesterol and diabetes, which may in turn lead to a heart attack over time," said Leah E. Cahill, Ph.D., study lead author and Postdoctoral Research Fellow in the Department of Nutrition at Harvard School of Public Health in Boston, Mass.
"Our study group has spent decades studying the health effects of diet quality and composition, and now this new data also suggests overall dietary habits can be important to lower risk of coronary heart disease," said Eric Rimm, Sc.D., senior author and Associate Professor of Epidemiology and Nutrition, Harvard School of Public Health and Associate Professor of Medicine at the Harvard Medical School.
Men who reported eating breakfast ate on average one more time per day than those who skipped breakfast, implying that those who abstained from breakfast were not eating additional make-up meals later in the day. Although there was some overlap between those who skipped breakfast and those who ate late at night, 76 percent of late-night eaters also ate breakfast, researchers said.
The study collected comprehensive questionnaire data from the participants and accounted for many important factors such as TV watching, physical activity, sleep, diet quality, alcohol intake, medical history, BMI, and social factors like whether or not the men worked full-time, were married, saw their doctor regularly for physical exams, or smoked currently or in the past.
While the current study group was composed of men who were of 97 percent white European descent, the results should also apply to women and other ethnic groups, but this should be tested in additional studies, researchers said.
"Don't skip breakfast," Cahill said. "Eating breakfast is associated with a decreased risk of heart attacks. Incorporating many types of healthy foods into your breakfast is an easy way to ensure your meal provides adequate energy and a healthy balance of nutrients, such as protein, carbohydrates, vitamins and minerals. For example, adding nuts and chopped fruit to a bowl of whole grain cereal or steel-cut oatmeal in the morning is a great way to start the day."
Friday, July 19, 2013
Light Drinking My Not Offer Health Benefits After All
As a class, people who don't drink at all have a higher mortality risk than light drinkers. But nondrinkers are a diverse bunch, and the reasons people have for abstaining affects their individual mortality risk, in some cases lowering it on par with the risk for light drinkers, according to a University of Colorado study.
Multiple studies have shown that the likelihood of dying for people who drink increases as they consume more alcohol. Those same studies have shown that a person's mortality risk also increases at the other end of the spectrum — among people who choose not to drink at all — though the risk is still much less than for heavy drinkers.
Some researchers have hypothesized that the increased mortality among nondrinkers could be related to the fact that light alcohol consumption — drinking, on average, less than one drink a day — might actually protect people from disease and reduce their stress levels.
But researchers at the University of Colorado Boulder, working with colleagues at the University of Colorado Denver, decided to examine whether characteristics of different subgroups of nondrinkers could explain the increased mortality risk.
"Among nondrinkers, people have all sorts of background reasons for why they don't drink," said sociology Professor Richard Rogers, director of CU-Boulder's Population Program in the Institute of Behavioral Science. "We wanted to tease that out because it's not really informative to just assume that nondrinkers are a unified group."
For the new study, published in last month's issue of the journal Population Research and Policy Review, Rogers and his colleagues relied on data collected in 1988 by the National Health Interview Survey about the drinking habits of more than 41,000 people from across the United States. The researchers also had access to information about which respondents died between taking the survey and 2006.
During the survey, nondrinkers were asked to provide their reasons for not drinking. Possible answers ranged from "don't socialize very much" to "am an alcoholic" to "religious or moral reasons."
The research team divided nondrinkers into three general categories: "abstainers," or people who have never had more than 12 drinks in their lives; "infrequent drinkers," or people who have fewer than 12 drinks a year; and "former drinkers." Each category was further divided using a statistical technique that grouped people together who gave similar clusters of reasons for not drinking.
The team then calculated the mortality risk for each subgroup compared with the mortality risk for light drinkers, and they found that the risks varied markedly.
Abstainers who chose not to drink for a cluster of reasons that included religious or moral motivations, being brought up not to drink, responsibilities to their family, as well as not liking the taste, had similar mortality risks over the follow-up period to light drinkers.
"So this idea that nondrinkers always have higher mortality than light drinkers isn't true," Rogers said. "You can find some groups of nondrinkers who have similar mortality risks to light drinkers."
The other subgroup of abstainers — whose largest reason for not drinking appeared to be a dislike of the taste and to a lesser degree family responsibilities, religious or moral motivations or upbringing — had a 17 percent higher mortality risk over the follow-up period compared with light drinkers.
The scientists also found that infrequent drinkers generally had a slightly higher mortality risk than light drinkers. Former drinkers, however, had the highest mortality risk of all nondrinkers. Former drinkers whose cluster of reasons for not drinking now included being an alcoholic and problems with drinking, for example, had a 38 percent higher mortality risk than light drinkers over the follow-up period.
By comparison, people who drink between one and two drinks per day, on average, have a 9 percent higher mortality rate than light drinkers, while people who drink between two and three drinks per day have a 49 percent higher mortality. People who consume more than three drinks per day had a 58 percent higher mortality risk over the follow-up period compared with light drinkers.
Despite confirming that some subgroups of nondrinkers have a higher mortality rate than light drinkers, it doesn't necessarily follow that those people's mortality rates would fall if they began drinking, Rogers said. For example, people who were problem drinkers in the past might increase their mortality risk further by starting to drink again.
Also, people who don't drink at all, as a group, have lower socioeconomic characteristics than light drinkers, which could be one of the underlying causes for the mortality differences, Rogers said. In that case, starting to drink without changing a person's socioeconomic status also would not likely lower mortality rates.
"I think the idea that drinking could be somewhat beneficial seems like it's overstated," Rogers said. "There may be other factors that lower mortality for light drinkers. It's not just the act of drinking."
Thursday, July 18, 2013
Vigorous exercise may lower stroke risk
Here's yet another reason to get off the couch: new research findings suggest that regularly breaking a sweat may lower the risk of having a stroke.
A stroke can occur when a blood vessel in the brain gets blocked. As a result, nearby brain cells will die after not getting enough oxygen and other nutrients. A number of risk factors for stroke have been identified, including smoking, high blood pressure, diabetes and being inactive.
For this study, published in the journal Stroke, Michelle N. McDonnell, Ph.D., from the University of South Australia, Adelaide and her colleagues obtained data from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. REGARDS is a large, long-term study funded by the NIH National Institute of Neurological Disorders and Stroke (NINDS) to look at the reasons behind the higher rates of stroke mortality among African-Americans and other residents living in the Southeastern United States.
"Epidemiological studies such as REGARDS provide an important opportunity to explore race, genetics, environmental, and lifestyle choices as stroke risk factors," said Claudia Moy, Ph.D., program director at NINDS.
Over 30,000 participants supplied their medical history over the phone. The researchers also visited them to obtain health measures such as body mass index and blood pressure. At the beginning of the study, the researchers asked participants how many times per week they exercised vigorously enough to work up a sweat. The researchers contacted participants every six months to see if they had experienced a stroke or a mini-stroke known as a transient ischemic attack (TIA). To confirm their responses, the researchers reviewed participants' medical records.
The researchers reported data for over 27,000 participants who were stroke-free at the start of the study and followed for an average of 5.7 years. One-third of participants reported exercising less than once a week. Study subjects who were inactive were 20 percent more likely to experience a stroke or TIA than participants who exercised four or more times a week.
The findings revealed that regular, moderately vigorous exercise, enough to break a sweat, was linked to reduced risk of stroke. Part of the protective effect was due to lower rates of known stroke risk factors such as hypertension, diabetes, obesity and smoking.
"Our results confirm other research findings but our study has the distinct advantage of including larger numbers, especially larger numbers of women as well as blacks, in a national population sample so these provide somewhat more generalizable results than other studies," said Virginia Howard, Ph.D., senior author of the study from the School of Public Health, University of Alabama at Birmingham.
The researchers also looked at the data according to gender. After the researchers accounted for age, race, socioeconomic factors (education and income) and stroke risk factors, the results revealed that men who exercised at least four times a week still had a lower risk of stroke than men who exercised one to three times per week. In contrast, there was no association between frequency of exercise and stroke risk among women in the study. However, there was a trend towards a similar reduction in stroke risk for those who exercised one to three times a week and four or more times a week compared to those who were inactive.
"This could be related to differences in the type, duration, and intensity of physical activity between men and women," said Dr. Howard. "This could also be due to differences in the perception of what is intense physical activity enough to work up a sweat."
The results should encourage doctors to stress the importance of exercise when speaking with their patients, Dr. Howard said.
"Physical inactivity is a major modifiable risk factor for stroke. This should be emphasized in routine physician check-ups along with general education about the benefits of exercise on stroke risk factors including high blood pressure, diabetes and being overweight or obese," she said.
The study suggests that men should consider exercising at least four times a week.
REGARDS will continue to assess stroke risk factors to look for long-term patterns in the study population. "Findings from this study, including the current physical activity results, will ultimately help us to identify potential targets for immediate intervention as well as for future clinical trials aimed at preventing stroke and its consequences," said Dr. Moy.
Wednesday, July 17, 2013
Vitamin D supplements could help prevent mobility problems
Vitamin D-deficient older individuals are more likely to struggle with everyday tasks such as dressing or climbing stairs, according to a recent study accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology & Metabolism (JCEM).
Scientists estimate many as 90 percent of older individuals are vitamin D deficient. The vitamin – typically absorbed from sunlight or on a supplementary basis through diet – plays a key role in bone and muscle health. Vitamin D deficiency can lead to a decline in bone density, muscle weakness, osteoporosis or broken bones.
"Seniors who have low levels of vitamin D are more likely to have mobility limitations and to see their physical functioning decline over time," said the study's lead author, Evelien Sohl, MSc, of VU University Medical Center in Amsterdam, the Netherlands. "Older individuals with these limitations are more likely to be admitted to nursing homes and face a higher risk of mortality."
Using data from an ongoing Dutch cohort study (The Longitudinal Aging Study Amsterdam), the researchers examined among two groups – 762 people between the ages of 65 and 88, and 597 people between the ages of 55 and 65 – over the course of six years. Using blood test results, the subjects were split into groups with the highest, moderate and lowest vitamin D levels. To assess mobility limitations, participants were asked about their ability to perform routine tasks, including sitting down and standing up from a chair or walking outside for 5 minutes without resting.
Among the older group of participants, people with the lowest vitamin D levels were 1.7 times more likely to have at least one functional limitation compared to those with the highest vitamin D levels. In the younger cohort, individuals with low vitamin D levels were twice as likely to have at least one physical limitation.
While the majority of the people in the older cohort's top two vitamin D groups did not report any physical limitations, 70 percent of the people with the lowest vitamin D levels had at least one limitation.
In addition, the study found vitamin D-deficient individuals were more likely to develop additional limitations over time. The older cohort reported more mobility issues after three years, while the younger cohort developed additional limitations over the course of six years.
"The findings indicate low vitamin D levels in older individuals may contribute to the declining ability to perform daily activities and live independently," Sohl said. "Vitamin D supplementation could provide a way to prevent physical decline, but the idea needs to be explored further with additional studies."
Tuesday, July 16, 2013
Vitamins and minerals can boost energy and enhance mood
Vitamin and mineral supplements can enhance mental energy and well-being not only for healthy adults but for those prone to anxiety and depression, according to a July 15 panel discussion at the 2013 Institute of Food Technologists (IFT) Annual Meeting & Food Expo® held at McCormick Place.
Bonnie Kaplan, Ph.D., professor in the faculty of medicine at the University of Calgary, Alberta, Canada, said Monday vitamins and mineral supplements can be the alternative to increasing psychiatric medicines for symptom relief of anxiety and depression. The supplements, she said, also can provide the mental energy necessary to manage stress, enhance mood and reduce fatigue.
In a series of studies she recently conducted in Canada, Kaplan found of the 97 adults with diagnosed mood disorders who kept a three-day food record, a higher intake of vitamins and minerals were significantly correlated with overall enhanced mental functioning.
Other vitamins that have been known to enhance mood, said C.J. Geiger, Ph.D., president of Geiger & Associates, LLC, and research associate professor in the division of nutrition at the University of Utah, include 5-Hydroxytryptophan (5 HTP), Vitamins B and D, as well as ginkgo biloba and Omega 3.
In her research, Geiger has found most adults define energy throughout the day as peaking mid-morning, falling to a valley in the afternoon after lunch and recovering with a pickup in late afternoon, settling back down before bedtime. However, these peaks and valleys did vary with gender, age and climate. She said many adults are known to use coffee, soft drinks, chocolate and candy bars as well as energy drinks, bars and chews with high sugar boosts to maintain energy throughout the day. She found other adults ate more frequent, smaller meals to sustain energy while making time for lots of rest and exercise.
High-fiber Snacks May Aid Satiety, Weight Loss
Healthy snacks that promote a feeling of fullness (satiety) may reduce the amount of food intake at subsequent meals and limit overall food consumption, according to a presentation today at the 2013 Institute of Food Technologists (IFT) Annual Meeting & Food Expo in Chicago®.
“Appetite control is an area of weight management that is receiving increased attention as the food industry aims to provide consumers with foods that will keep them fuller for longer, reducing inter-meal hunger and overall energy intake,” said Roberta Re, Ph.D., nutrition research manager at Leatherhead Food Research in Surrey, England.
While the amount, frequency and types of snacks consumed in the U.S. and throughout the world continues to contribute to the obesity epidemic, some snacks, such as peanuts, nuts and other high-fiber snacks, may limit overall daily food consumption.
Re referenced a study in which participants who regularly consumed almonds as a mid-morning snack reported increased feelings of satiety “resulting in a reduced energy intake at lunch and dinner with no increase in overall” calorie intake. In another study, participants’ overall daily intake was lowered after they received a regular portion of cereal as a snack each day for six weeks.
Kantha Shelke, Ph.D., principal at Corvus Blue, LLC, said that food manufacturers are working to meet consumer needs for savory, satisfying snacks that also are healthy.
“You can make something just as delicious with a greater mixture of ingredients,” said Shelke. “You also can increase quantity while limiting energy density. The satiety lasts longer, and there’s no penalty for enjoyment.”
Aspirin Every Other Day May Lower Women's Colon Cancer Risk
Taking a low-dose aspirin every other day may reduce the risk of colorectal cancer, according to a study that focused on nearly 40,000 women aged 45 and older.
The protection does seem to take some time to surface, said researcher Nancy Cook, a professor of medicine at Brigham and Women's Hospital and Harvard Medical School. "After 10 years, we started to see an effect," she noted.
"After 18 years of follow-up, we saw a 20 percent reduction in colon cancer over the whole time period," she said. When they looked at the 10-to-18 year mark, the reduction was 42 percent, she said.
However, risks linked with aspirin, such as gastrointestinal bleeding, must be considered, Cook said.
The study, funded by the U.S. National Cancer Institute and U.S. National Heart, Lung, and Blood Institute, is published July 16 in the Annals of Internal Medicine.
Aspirin has been long known for its protective effects on heart health, but the protective effect of aspirin on colon and rectal cancer has only been found more recently. "In the past three years, analyses of trials conducted for cardiovascular health have begun to show an effect on colon cancer as well," Cook said.
Cook and her team followed women enrolled in the Women's Health Study, a trial that evaluated the benefits and risks of low-dose aspirin and vitamin E in preventing both cardiovascular disease and cancers.
The study began in 1993 and ended in 2004. The women had no history of cancer (except nonmelanoma skin cancer), cardiovascular disease or other major chronic illness when they enrolled.
The women assigned to the aspirin group were told to take a low dose -- 100 milligrams -- of aspirin every other day. The comparison group took placebo pills on alternate days.
After the study ended, the researchers continued to follow more than 33,000 women through March 2012. The women were told to continue the regimen, although the researchers no longer provided the pills.
The researchers tracked colorectal cancer, along with other cancers. They found the 20 percent lower colorectal cancer incidence over the entire 18-year follow-up.
They did not find a difference with cancer deaths between groups, but Cook said there may not have been enough women to show a comparative difference from a statistical point of view.
Cook found no difference in colorectal polyps between groups. Polyps are removed when they are found on colonoscopy as they can progress to cancer.
The aspirin group had more gastrointestinal bleeding, a known side effect, and more peptic ulcers. While 8.3 percent of the aspirin group had GI bleeding, 7.3 percent of the placebo group did. Peptic ulcers affected 7.3 percent of the aspirin group but only 6.2 percent of the placebo group.
While the study included only women, Cook said the results would probably apply to men, too. Other aspirin studies that looked at the effects of the drug, she said, have included mainly men.
Even with the double benefit of heart and colon protection, Cook said, "You really need to balance risks and benefits."
Dr. Anthony Starpoli, a gastroenterologist at Lenox Hill Hospital in New York City, agreed that patients should be carefully selected for aspirin therapy.
Before a doctor suggests aspirin for the colon protection, Starpoli said, the important question is: "Am I really reducing their risk of colon cancer or am I increasing their risk of GI bleeding?"
The strength of the study, he said, is the large number of women. However, he does not think the findings translate to a global recommendation that everyone over 45 take alternate day aspirin for colon cancer risk reduction. "There may be a subgroup of patients at higher risk who could benefit."
Those with a family history of colon cancer or who have had polyps have a higher than average risk.
The side effect of GI bleeding needs to be taken seriously, Starpoli said. "The nature of GI bleeding from nonsteroidal anti-inflammatories [NSAIDs] or aspirin is somewhat unpredictable," he said. And it can be serious and even fatal.
For those hoping to take an aspirin for the double benefit of heart and colon health, would alternate day protect their heart enough?
Generally, daily aspirin is recommended for heart disease risk reduction, Cook said. However, "the Physicians' Health Study showed a benefit for alternate day, but the dose was 325 milligrams of regular aspirin," she added.
This year, more than 102,000 new colon cancers and more than 40,000 rectal cancers will be diagnosed, the American Cancer Society estimates.
Prostate cancers are fewer, smaller on walnut-enriched diet
New research from the School of Medicine at The University of Texas Health Science Center San Antonio indicates that eating a modest amount of walnuts can protect against prostate cancer.
The study is described in the journal Cancer Investigation. Researchers at the UT Health Science Center injected immune-deficient mice with human prostate cancer cells. Within three to four weeks, tumors typically start to grow in a large number of these mice. The study asked whether a walnut-enriched diet versus a non-walnut diet would be associated with reduced cancer formation. A previous study found this to be true for breast cancer.
Results
Three of 16 mice (18 percent) eating the walnut-enriched diet developed prostate tumors, compared with 14 of 32 mice (44 percent) on the non-walnut control diet. Also of note, the final average tumor size in the walnut-fed animals was roughly one-fourth the average size of the prostate tumors that developed in the mice eating the control diet.
"We found the results to be stunning because there were so few tumors in animals consuming the walnuts and these tumors grew much more slowly than in the other animals," said study senior author Russel Reiter, Ph.D., professor of cellular and structural biology at the Health Science Center. "We were absolutely surprised by how highly effective the walnut diet was in terms of inhibition of human prostate cancer."
Percentage of diet
The mice consumed a diet typically used in animal studies, except with the addition of a small amount of walnuts pulverized into a fine powder to prevent the rodents from only eating the walnuts. "The walnut portion was not a large percentage of the diet," Dr. Reiter said. "It was the equivalent to a human eating about 2 ounces, or two handfuls, a day, which is not a lot of walnuts."
Study co-author W. Elaine Hardman, Ph.D., of the Joan C. Edwards School of Medicine at Marshall University, published a study in 2011 that showed fewer and smaller tumors among walnut-fed mice injected with human breast cancer cells. Dr. Hardman formerly was a faculty member at the Health Science Center.
"The data to date suggest that using walnuts on a regular basis in the diet may be beneficial to defer, prevent or delay some types of cancer, including breast and prostate," Dr. Reiter said.
Monday, July 15, 2013
Dietary risk factors for colorectal cancer
Fizzy drinks, cakes, biscuits, crisps (potato chips) and desserts have all been identified as risk factors for bowel cancer, according to new research.
The study is the first of its kind to find a positive link between the disease and a diet high in foods that contain a lot of sugar and fat.
Researchers looked at risk factors including diet, levels of physical activity and smoking in a large Scottish study.
A team from the University of Edinburgh examined more than 170 foods. These included fruit, vegetables, fish and meat, as well as high-energy snack foods like chocolates, nuts and crisps and fruit drinks including fruit squash.
Scientists reported links with some established risk factors of colorectal cancer – such as family history of cancer, physical activity and smoking. They also identified new factors including high intake of high energy snacks and sugar-sweetened drinks.
The study – which used data from the Scottish Colorectal Cancer Study – carried out in 2012, builds on previous research into the link between bowel cancer and diet. Those studies identified two distinct eating patterns – one, high in fruit, vegetables and other healthy foods and the other – known as the western pattern, which is high in meat, fat and sugar.
The healthy dietary pattern was found to be associated with a decreased colorectal cancer risk, while the western dietary pattern was found to be associated with an increased risk.
Dr Evropi Theodoratou, of the University of Edinburgh's School of Molecular, Genetic and Population Health Sciences, said: "What we have found is very interesting and it merits further investigation using large population studies. While the positive associations between a diet high in sugar and fat and colorectal cancer do not automatically imply 'cause and effect', it is important to take on board what we've found – especially as people in industrialised countries are consuming more of these foods."
Thursday, July 11, 2013
Should men keep consuming fish or fish oil supplements?
(Women of course should keep on consuming fish or fish oil supplements. In addition to all the benefits listed below:
Regular use of fish oil supplements, which contain high levels of the omega-3 fatty acids, EPA and DHA, was linked with a 32 percent reduced risk of breast cancer.
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.)
The report about the Omega-3 very strong connection to prostate cancer is very disturbing, although personally, that risk is in the past. Nevertheless, for almost all males, a risk-reward calculation should be made of the risk vs.the benefits of Omega-3 consumption. Because, while the risks are great, so are the rewards.
Here's what I wrote in 2008:
Jon's Health Tips: Eating Fish
I eat a lot of fish – mostly salmon, but lots of other fish as well. However, I avoid swordfish and tuna, especially tuna steaks and albacore because of high levels of mercury, and tilapia because of high levels of omega-6. I eat fish because its healthy and I like it, and when I’m eating fish I’m not eating meat. I supplement my fish consumption with fish oil or flaxseed oil on days that I do eat meat.
My daughter, who is a pediatrician and vegetarian, also uses flaxseed oil and gives her 3 children fish oil supplements.
Here’s why: (see link above for details on each of these)
Fish reduces asthma and allergies
Eating fish may explain very low levels of heart disease in Japan
Eating Fish May Prevent Memory Loss and Stroke
A diet rich in fish and omega-3 oils, may lower your risk of dementia and Alzheimer’s disease, according to a study published in the November 13, 2007, issue of Neurology®, the medical journal of the American Academy of Neurology. People who ate fish at least once a week had a 35-percent lower risk of Alzheimer’s disease and 40-percent lower risk of dementia.
Oily fish can protect against rheumatoid arthritis
Eating fish and foods with omega-3 fatty acids linked to lower risk of age-related eye disease
The evidence of health benefits has grown even stronger since then. Here is a small sampling:
1. There is mounting evidence that omega-3 fatty acids from fish or fish oil supplements not only help prevent cardiovascular diseases in healthy individuals, but also reduce the incidence of cardiac events and mortality in patients with existing heart disease. A new study, published in the August 11, 2009, issue of the Journal of the American College of Cardiology, extensively reviews data from a broad range of studies in tens of thousands of patients and sets forth suggested daily targets for omega-3 consumption.
2. Omega-3 Fatty Acids=Reduced Risk of Colon Cancer
3. Omega-3 fatty acid kills neuroblastoma cancer cells
4. New research has shown for the first time that omega-3 in fish oil could "substantially and significantly" reduce the signs and symptoms of osteoarthritis.
5. Eating at least two servings of oily fish a week is moderately but significantly associated with a reduced risk of stroke, finds a study published on bmj.com today. But taking fish oil supplements doesn't seem to have the same effect, say the researchers.
And most important:
6. Older adults who have higher levels of blood omega-3 levels—fatty acids found almost exclusively in fatty fish and seafood—may be able to lower their overall mortality risk by as much as 27% and their mortality risk from heart disease by about 35%, according to a new study from Harvard School of Public Health (HSPH) and the University of Washington. Researchers found that older adults who had the highest blood levels of the fatty acids found in fish lived, on average, 2.2 years longer than those with lower levels.
Wednesday, July 10, 2013
Study confirms link between omega-3 fatty acids and increased prostate cancer risk
Consumption of fatty fish and fish-oil supplements linked to 71 percent higher risk
A second large, prospective study by scientists at Fred Hutchinson Cancer Research Center has confirmed the link between high blood concentrations of omega-3 fatty acids and an increased risk of prostate cancer.
Published July 11 in the online edition of the Journal of the National Cancer Institute, the latest findings indicate that high concentrations of EPA, DPA and DHA – the three anti-inflammatory and metabolically related fatty acids derived from fatty fish and fish-oil supplements – are associated with a 71 percent increased risk of high-grade prostate cancer. The study also found a 44 percent increase in the risk of low-grade prostate cancer and an overall 43 percent increase in risk for all prostate cancers.
The increase in risk for high-grade prostate cancer is important because those tumors are more likely to be fatal.
The findings confirm a 2011 study published by the same Fred Hutch scientific team that reported a similar link between high blood concentrations of DHA and a more than doubling of the risk for developing high-grade prostate cancer. The latest study also confirms results from a large European study.
"The consistency of these findings suggests that these fatty acids are involved in prostate tumorigenesis and recommendations to increase long-chain omega-3 fatty acid intake, in particular through supplementation, should consider its potential risks," the authors wrote.
"We've shown once again that use of nutritional supplements may be harmful," said Alan Kristal, Dr.P.H., the paper's senior author and member of the Fred Hutch Public Health Sciences Division. Kristal also noted a recent analysis published in the Journal of the American Medical Association that questioned the benefit of omega-3 supplementation for cardiovascular diseases. The analysis, which combined the data from 20 studies, found no reduction in all-cause mortality, heart attacks or strokes.
"What's important is that we have been able to replicate our findings from 2011 and we have confirmed that marine omega-3 fatty acids play a role in prostate cancer occurrence," said corresponding author Theodore Brasky, Ph.D., a research assistant professor at The Ohio State University Comprehensive Cancer Center who was a postdoctoral trainee at Fred Hutch when the research was conducted. "It's important to note, however, that these results do not address the question of whether omega-3's play a detrimental role in prostate cancer prognosis," he said.
Kristal said the findings in both Fred Hutch studies were surprising because omega-3 fatty acids are believed to have a host of positive health effects based on their anti-inflammatory properties. Inflammation plays a role in the development and growth of many cancers.
It is unclear from this study why high levels of omega-3 fatty acids would increase prostate cancer risk, according to the authors, however the replication of this finding in two large studies indicates the need for further research into possible mechanisms. One potentially harmful effect of omega-3 fatty acids is their conversion into compounds that can cause damage to cells and DNA, and their role in immunosuppression. Whether these effects impact cancer risk is not known.
The difference in blood concentrations of omega-3 fatty acids between the lowest and highest risk groups was about 2.5 percentage points (3.2 percent vs. 5.7 percent), which is somewhat larger than the effect of eating salmon twice a week, Kristal said.
The current study analyzed data and specimens collected from men who participated in the Selenium and Vitamin E Cancer Prevention Trial (SELECT), a large randomized, placebo-controlled trial to test whether selenium and vitamin E, either alone or combined, reduced prostate cancer risk. That study showed no benefit from selenium intake and an increase in prostate cancers in men who took vitamin E.
The group included in the this analysis consisted of 834 men who had been diagnosed with incident, primary prostate cancers (156 were high-grade cancer) along with a comparison group of 1,393 men selected randomly from the 35,500 participants in SELECT.
Vitamin D deficiency reduces bone quality
Everyone knows that as we grow older our bones become more fragile. Now a team of U.S. and German scientists led by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley has shown that this bone-aging process can be significantly accelerated through deficiency of vitamin D – the sunshine vitamin.
Vitamin D deficiency is a widespread medical condition that has been linked to the health and fracture risk of human bone on the basis of low calcium intake and reduced bone density. However, working at Berkeley Lab’s Advanced Light ALS), a DOE national user facility, the international team demonstrated that vitamin D deficiency also reduces bone quality.
“The assumption has been that the main problem with vitamin D deficiency is reduced mineralization for the creation of new bone mass, but we’ve shown that low levels of vitamin D also induces premature aging of existing bone,” says Robert Ritchie, who led the U.S. portion of this collaboration. Ritchie holds joint appointments with Berkeley Lab’s Materials Sciences Division and the University of California (UC) Berkeley’s Materials Science and Engineering Department.
“Unraveling the complexity of human bone structure may provide some insight into more effective ways to prevent or treat fractures in patients with vitamin D deficiency,” says Björn Busse, of the Department of Osteology and Biomechanics at the University Medical Center in Hamburg, Germany, who led the German portion of the team.
Ritchie and Busse have reported their findings in the journal Science Translational Medicine. The paper is titled “Vitamin D Deficiency Induces Early Signs of Aging in Human Bone, Increasing the Risk of Fracture.” Co-authors also include Hrishikesh Bale, Elizabeth Zimmermann, Brian Panganiban, Holly Barth, Alessandra Carriero, Eik Vettorazzi, Josef Zustin, Michael Hahn, Joel Ager, Klaus Püschel and Michael Amling.
Vitamin-D is essential for the body to absorb calcium. The body normally synthesizes vitamin D in the skin following exposure to sunlight – hence the “sunshine” moniker. However, when vitamin D serum concentrations become deficient, the body will remove calcium from bone to maintain normal calcium blood levels. This removal of calcium from existing bone hampers the mineralization process required for the formation of new bone mass. In children, vitamin D deficiency can lead to rickets. In adults, vitamin D deficiency causes osteomalacia, a softening of the bones associated with defective mineralization that results in bone pain, muscle weakness, and increased risk of bone deformation and fracture. While treatments with vitamin D and calcium supplements are effective, success has been achieved with only modest increases in bone mineral density, suggesting other factors also play a role in reducing fracture risks.
“We hypothesized that restoring the normal level of vitamin D not only corrects the imbalance of mineralized and non-mineralized bone quantities, but also initiates simultaneous multiscale alterations in bone structure that affects both the intrinsic and extrinsic fracture mechanisms,” Ritchie says.
To test this hypothesis, Busse and his German team collected samples of iliac crest bone cores from 30 participants, half of whom were deficient in vitamin D and showed early signs of osteomalacia. For this study, a normal vitamin D level was defined as a serum concentration of 20 micrograms per liter or higher. For the vitamin D deficiency group the mean serum concentration was 10 micrograms per liter.
The bone samples were sent to Ritchie and his team for analysis at the ALS using Fourier Transform Infrared (FTIR) spectroscopy and X-ray computed microtomography. The FTIR spectroscopy capabilities of ALS beamlines 1.4.3 and 5.4.1 provide molecular-level chemical information, and ALS Beamline 8.3.2 provides non-destructive 3D imaging at a resolution of approximately one micron.
“We were interested in spatially resolved data that would help us to follow the formation of cracks under mechanical loading,” Ritchie says. “The ALS beamlines enabled us to measure the structure/composition and mechanical properties of the bone samples at different size-scales, ranging from nanometers to micrometers. We measured the resistance to crack growth and by following crack growth in real-time were able to observe how cracks and structure interact. This enabled us to relate mechanical properties to specific structural changes.”
Ritchie and his team found that while vitamin D-deficient subjects had less overall mineralization due to a reduction of mineralized bone, underneath the new non-mineralized surfaces, the existing bone was actually more heavily mineralized, and displayed the structural characteristics – mature collagen molecules and mineral crystals – of older and more brittle bone.
“These islands of mineralized bone were surrounded by a collagenous boundary that prevented them from being properly remodeled,” Busse says. “Cut off from a supply of osteoclasts, the cells that normally remodel the bone, these isolated sections of mineralized bone begin to age, even as overall bone mineralization decreases from a lack of calcium.”
Says Ritchie, “In situ fracture mechanics measurements and CT-scanning of the crack path indicated that vitamin D deficiency increases both the initiation and propagation of cracks by 22- to 31-percent.”
From their study, Busse, Ritchie and their co-authors say that vitamin-D levels should be checked and kept on well-balanced levels to maintain the structural integrity of bones and avoid mineralization defects and aging issues that can lead to a risk of fractures.
Tuesday, July 9, 2013
Statin use linked to few side effects
Statins -- the popular class of cholesterol-lowering drugs used widely to prevent recurrent heart disease or stroke as well as risk for having a first cardiac or stroke event -- appear to cause few side effects, according to new research reported in Circulation: Cardiovascular Quality and Outcomes.
Researchers conducted the largest meta-analysis on statin side effects to date, reviewing data from 135 previous drug studies to evaluate the safety of the seven statins on the market. They concluded "as a class, adverse events associated with statin therapy are not common."
Researchers noted that simvastatin and pravastatin, the generic names of the brands Zocor and Pravachol, were found to have the best safety profile in the class. This is particularly true when patients were prescribed low to moderate doses of those statins, said Huseyin Naci, M.H.S., the study's lead author and a doctoral candidate at the London School of Economics and Political Science and research fellow at Harvard Medical School's Department of Population Medicine.
Researchers also noted a 9 percent increased risk of diabetes among statin users. But according to a previous landmark study, 250 patients need to be treated with a statin for one case of diabetes to be diagnosed.
"I am concerned that patients may misunderstand this small increase in risk and stop adhering to their medications," Naci said. The proven ability of statins to significantly cut the rate of death and hospitalization in patients who have heart disease outweighs the "small increase in diabetes risk," he said.
Researchers reviewed trials published between 1985 and early 2013, which included almost 250,000 patients. On average, the trials lasted a bit longer than a year. Some compared one statin to another, while others compared a statin to an inactive placebo, which is often called a sugar pill or dummy pill.
The study also found that statins were not linked to an increase in cancer risk. However, the drugs were associated with a typically reversible increase in liver enzymes, which Naci said still resulted in a very low rate of actual liver toxicity in statin patients.
"Although the benefits of statins clearly outweigh risks at the population level, individualizing such benefits and risks is more difficult," he said. "This brings into sharp focus the importance of identifying the individuals who stand to benefit the most from statin therapy.
Although the risk of developing diabetes is low, what this risk would amount to over time is simply not known based on the existing evidence," Naci said.
Placebo effect largely ignored in studies involving programs improving brainpower
Many brain-training companies tout the scientific backing of their products – the laboratory studies that reveal how their programs improve your brainpower. But according to a new report, most intervention studies like these have a critical flaw: They do not adequately account for the placebo effect.
The new analysis appears in the journal Perspectives on Psychological Science.
The results of psychological interventions, like medical ones, must be compared to improvements in a control condition, said University of Illinois psychology professor Daniel Simons, who co-wrote the article with Walter Boot, Cary Stothart and Cassie Stutts, of Florida State University. In a clinical trial for a new drug, some participants receive a pill with the critical ingredients, and others receive an identical-looking pill that is inert – a placebo. Because participants cannot tell which they received, people in each condition should be equally likely to expect improvements.
In contrast, for most psychology interventions, participants know what's in their "pill," Simons said.
"It's not possible to use a brain-training program for 10 hours without knowing the type of training you received," he said. "People can form expectations for what will improve based on their experiences with the training tasks, and the existence of differences in expectations between people in treatment and control groups potentially undermines any claim that improvements were due to the treatment itself. Not one of the studies cited by the brain-training companies looks at differing expectations between the groups."
Merely having an "active control group," one that does something for the same amount of time as the treatment group, does not protect against the placebo effect, Simons said. A treatment group that completes an intensive memory-training regimen might expect improved performance on other cognitive tasks assessing memory. A control group that does crossword puzzles or watches DVDs for the same amount of time likely won't expect the same amount of improvement on the same tasks, he said.
"These problems are not limited to brain-training studies," Simons said. "They hold true for almost all intervention studies."
To illustrate the pervasiveness of this problem, the researchers examined expectations for improvement in studies of the effect of playing action video games on measures of perception and attention.
"Such studies find greater improvements in performance on attention and perception tasks after training with action video games than after training with non-action games for the same amount of time," Boot said. "However, even with this sort of active control condition, these interventions still are at risk for differential placebo effects."
The researchers measured expectations in two survey studies involving 200 participants each. Participants watched either a short video of an action game ("Unreal Tournament") or one of the games commonly used as controls in these studies ("Tetris" or "The Sims"). They then read descriptions of the cognitive tests used in the studies, watched short videos of the tests, and answered questions about whether they thought their performance on the tests would improve as a result of training on the video game they had viewed.
The results showed that expectations for improvement were greater for the action-game group than for the control games on exactly the same tests that showed bigger improvements for action-game training in the intervention studies. In fact, the pattern of expected improvements exactly matched actual improvements seen in video game intervention studies, the researchers found.
"If expectations for improvement align perfectly with the actual improvements, then any claim that the treatment was effective is premature," Simons said. "Researchers must first eliminate differences in expectations across conditions."
"Even though participants in psychology interventions typically know the nature of their intervention – you can't play a video game without knowing the game you're playing – there are steps researchers can take to ensure that the advantages of the treatment group are not due to expectations," Boot said.
For example, researchers can mislead participants as to the expected benefits of a particular intervention, giving those in the control group higher expectations for improvement than those in the treatment group. Researchers also can assess expectations generated by treatments in a separate sample of participants to ensure that expectations do not differ between intervention and control treatments.
"Although placebo effects can be helpful as well, we need to know what causes improvements in an intervention," Simons said. "We don't want to recommend new therapies, change school curricula, or encourage the elderly to buy brain-training games if the benefits are just due to expectations for improvement. Only by using better active controls that equate for expectations can we draw definitive conclusions about the effectiveness of any intervention."
Outdated practice of annual cervical-cancer screenings may cause more harm than good
For decades, women between the ages of 21 and 69 were advised to get annual screening exams for cervical cancer. In 2009, however, accumulating scientific evidence led major guideline groups to agree on a new recommendation that women be screened less frequently: every three years rather than annually.
Despite the revised guidelines, about half of the obstetrician-gynecologists surveyed in a recent study said they continue to provide annual exams – an outdated practice that may be more harmful than helpful, said Drs. Russell Harris and Stacey Sheridan of the Cecil G. Sheps Center for Health Services Research at the University of North Carolina at Chapel Hill.
“Screening is not the unqualified good that we have advertised it to be,” they wrote in an editorial titled, “The Times They (May Be) A-Changin’: Too Much Screening is a Health Problem.” The editorial accompanied a research study reviewing physician practices around cervical-cancer screening and vaccination for human papilloma virus (HPV), which has been linked to cervical cancer.
The study, “Physicians Slow to Implement HPV Vaccination and Cervical Screening Guidelines,” was published July 9 in the American Journal of Preventive Medicine.
“Screening for cervical cancer and other cancers such as breast and prostate, has clear potential for harms as well as benefits, and these must be carefully weighed before a rational decision about screening can be made,” wrote Harris and Sheridan, who are professor and assistant professor of medicine, respectively, at UNC’s School of Medicine. They also hold adjunct appointments at UNC’s Gillings School of Global Public Health.
The study noted physicians said they were comfortable with longer testing intervals, but were concerned their patients might not come in for annual check-ups if Pap tests, the screening test for cervical cancer, were not offered. The problem, Harris said, is that annual Pap tests produce more abnormal results leading to additional, invasive testing that itself bring risks.
“Many women have ‘abnormal’ [Pap test] findings that are not cancer, but may be a ‘cancer precursor.’ We know that the great majority of these abnormal findings would never progress to actual invasive cancer, yet these women are referred” for further, more invasive testing, Harris said.
One such test, called a “colposcopy,” [cohl-PAH-scoh-pee], involves examining the cervix for possibly cancerous lesions, followed frequently by a biopsy, i.e., taking a small sample of the lesion, which can cause pain and bleeding, as well as potential psychological harm. “The screening test itself can raise concern about dreaded cancer; a positive screening test heightens this worry; finding a cancer precursor, even one of uncertain importance, just increases worry further,” they wrote.
The authors recognize the important benefit of screening for cervical and other cancers, but “screening every three years [for cervical cancer] retains about 95 percent of the benefit of annual screening, but reduces harms by roughly two-thirds.” Less-frequent screening also reduces costs significantly in terms of patient and physician time and laboratory testing supplies and other resources.
The newest cervical-cancer and HPV screening recommendations were released in March 2012, too recent to have been included in the July 9 study. Women should still begin Pap tests at age 21 and every three years afterward, but women between the ages of 30 and 65 may choose to extend the Pap test interval to every five years, provided they also get an HPV test, according to the U.S. Preventive Services Task Force and the American Cancer Society, among others. However, the authors added, “the debate about a do-less approach to screening—for cervical cancer and other conditions as well—is ongoing.”
The editorial concluded: “Bob Dylan sang about changing times before they actually changed, yet his singing moved the public discussion in a positive direction. Our sense is that the right song for the current discussion is about helping people come to appreciate the harms screening does … and move us toward a better balance of benefits and harms.”
Positive outlook = reduction in cardiac events such as heart attacks
People with cheerful temperaments are significantly less likely to suffer a coronary event such as a heart attack or sudden cardiac death, new Johns Hopkins research suggests.
Previous research has shown that depressed and anxious people are more likely to have heart attacks and to die from them than those whose dispositions are sunnier. But the Johns Hopkins researchers say their study shows that a general sense of well-being — feeling cheerful, relaxed, energetic and satisfied with life — actually reduces the chances of a heart attack.
A report on the research is published in the American Journal of Cardiology.
"If you are by nature a cheerful person and look on the bright side of things, you are more likely to be protected from cardiac events," says study leader Lisa R. Yanek, M.P.H., an assistant professor in the Division of General Internal Medicine at the Johns Hopkins University School of Medicine. "A happier temperament has an actual effect on disease and you may be healthier as a result."
Yanek cautioned that cheerful personalities are likely part of the temperament we are born with, not something we can easily change. While some have suggested it's possible that people lucky enough to have such a trait are also more likely to take better care of themselves and have more energy to do so, Yanek says her research shows that people with higher levels of well-being still had many risk factors for coronary disease but had fewer serious heart events.
She emphasized that the mechanisms behind the protective effect of positive well-being remain unclear. She also noted that her research offers insights into the interactions between mind and body, and could yield clues to those mechanisms in the future.
For the study, Yanek and her colleagues first looked at data from GeneSTAR (Genetic Study of Atherosclerosis Risk), a 25-year Johns Hopkins project sponsored by the National Institutes of Health to determine the roots of heart disease in people with a family history of coronary disease. They analyzed information gathered from 1,483 healthy siblings of people who had coronary events before the age of 60 and who were followed for five to 25 years. Siblings of people with early-onset coronary artery disease (CAD) are twice as likely of developing it themselves.
Among other things, study participants filled out well-being surveys and received a score, on a scale of 0 to 110, which gauged cheerful mood, level of concern about health, whether they were relaxed as opposed to anxious, energy level and life satisfaction. Over the course of an average 12-year follow-up, the researchers documented 208 coronary events — heart attacks, sudden cardiac death, acute coronary syndrome, and the need for stents or bypass surgery — in the sibling group.
The researchers found that participants' positive well-being was associated with a one-third reduction in coronary events; among those deemed at the highest risk for a coronary event, there was nearly a 50 percent reduction. The findings took into account other heart disease risk factors such as age, smoking, diabetes, high cholesterol levels and high blood pressure.
To validate their result, the researchers then looked at similar information in a general population using data from 5,992 participants in the first National Health and Nutrition Examination Survey (NHANES). In this population, over an average 16-year follow-up, there were 1,226 coronary events (20.5 percent). They found that this group also benefitted from a cheerful temperament, which reduced their risk of a coronary event by 13 percent.
The findings held whether the participants were white or African-American, men or women.
Low vitamin D blood levels = greater risk of heart disease in whites and Chinese, but not in blacks and Hispanics
Low vitamin D blood levels are linked to greater risk of heart disease in whites and Chinese, but not in blacks and Hispanics, according to a study appearing this week in JAMA, a journal published by the American Medical Association.
Growing evidence has suggested that low blood levels of 25-hydroxyvitamin are associated with higher risk of developing coronary heart disease among whites. Few of these studies included substantial numbers of people from other races.
Vitamin D levels tend to be lower among people from other racial and ethnic minority groups, and some of these populations have higher rates of heart disease. However, after correcting for other risk factors for heart disease in their large, multi-ethnic study group, the researchers reporting in the JAMA paper did not find an association between low vitamin D and cardiovascular events in their black and Hispanic study participants.
"Our study suggests that the results of ongoing vitamin D clinical trials conducted in white populations should be applied cautiously to people of other racial and ethnic backgrounds," said Cassianne Robinson-Cohen, the lead author for the JAMA paper. The senior author is Ian deBoer, University of Washington assistant professor of medicine, Division of Nephrology.
Robinson-Cohen is an affiliate instructor in epidemiology at the UW School of Public Health and a researcher at the Kidney Research Institute, where her team explores the genetic, metabolic and epidemiological factors related to heart and kidney disease.
She noted that the findings in their recent JAMA paper came from an observational study, not a randomized clinical trial, and could not guarantee cause and effect.
"Our future studies will examine the genetics affecting the levels and use of Vitamin D in the body to try to figure out why the link between low vitamin D blood levels and heart disease varies by race and ethnicity," she said. "We don't know for sure, but perhaps genes affecting the need for and use of vitamin D could have evolved to adapt to different levels of sun exposure in places where various ethnic subgroups of people originated."
IMAGE: Researchers will be studying genetic variations to try to understand why there are racial and ethnic differences in the need and use of vitamin D.
Click here for more information.
Her team plans to look for variations in genes known to mediate Vitamin D activation and metabolism. She said these genes have been identified, but at present scientists haven't determined how gene variation influences susceptibility to the adverse effects of low vitamin D.
The report published this week was from one of the projects within the Multi-Ethnic Study of Atherosclerosis. MESA is a major, long-term medical research effort sponsored by the National Heart Lung and Blood Institute of the National Institutes of Health. More than 6,800 men and women from six regions across the United States are participating in MESA. They were a diverse study group that was 38 percent white, 28 percent black, 22 percent Hispanic, and 12 percent Chinese. Robinson-Cohen and her team studied 6,436 MESA participants who enrolled between July 2000 and September 2002.
All participants were free of any known cardiovascular diseases at the time they enrolled, and had their blood levels of V25-hydroxyvitamin D measured. The mean age of participants at the start of the study was 62 (range 45 to 84 years) and slightly more than half were women.
The mean blood concentrations for whites was 30.1 ng/ml, Chinese 26.7, Hispanic 24.6, and blacks 19.2, The researchers tested the association of Vitamin D levels with the first incidence of coronary heart disease events – myocardial infarction, angina, cardiac arrest, or death from coronary heart disease — occurring from the start of the study until May 2012. During the eight-and-a-half year study, 361 participants had such an event. The researchers used several statistical risk analyses to check to see if links between blood vitamin D levels and coronary heart disease differed among white, black, Chinese and Hispanic populations.
"The differences in associations across race-ethnicity groups were consistent for both a broad and restricted definition of coronary heart disease and persisted after adjustment for known risk factors for coronary heart disease," the researchers noted in their paper.
Robinson-Cohen believes the strengths of the study are its size, duration, the use of several statistical analyses, the rigorous definition of heart disease events, and the efforts made to control for many confounding risk factors, such as age, gender, smoking, diabetes, blood pressure, cholesterol levels, physical activity, kidney disease,C-reactive protein concentrations, educational attainment, income and so on. A main weakness of the study, she said, is that it is observational, and therefore can't be ascertain cause and effect.
"To determine cause and effect, a large, multiethnic, randomized control clinical trial would need to be conducted," she said.
Robinson-Cohen pointed out, that beyond these specific results, the nature of the findings show the importance of designing medical research that includes a diverse ethnic and racial makeup of participants. Such multi-ethnic studies would help prevent cases where findings from one group are incorrectly applied to other groups.
"We need to make a bigger effort to design and fund medical studies with large enough representation of various racial and ethnic backgrounds that we don't draw ungrounded conclusions based on one group," Robinson-Cohen said.
Norway Issues Warnings on Farmed Salmon's Health Dangers
Article here:
# A Norwegian researcher has raised serious concerns about high levels of contaminants in farm-raised salmon
# She claims the type of contaminants detected in farmed salmon have a negative effect on brain development and is associated with autism, ADD / ADHD and reduced IQ. They can also affect your immune system and metabolism
# The Norwegian Health Department has issued new official recommendations to women of childbearing age or who are pregnant, suggesting they limit farmed salmon to a maximum of two meals per week due to potential toxicity
Monday, July 8, 2013
Exercise Reorganizes the Brain to Be More Resilient to Stress
Physical activity reorganizes the brain so that its response to stress is reduced and anxiety is less likely to interfere with normal brain function, according to a research team based at Princeton University.
The researchers report in the Journal of Neuroscience that when mice allowed to exercise regularly experienced a stressor -- exposure to cold water -- their brains exhibited a spike in the activity of neurons that shut off excitement in the ventral hippocampus, a brain region shown to regulate anxiety.
These findings potentially resolve a discrepancy in research related to the effect of exercise on the brain -- namely that exercise reduces anxiety while also promoting the growth of new neurons in the ventral hippocampus. Because these young neurons are typically more excitable than their more mature counterparts, exercise should result in more anxiety, not less. The Princeton-led researchers, however, found that exercise also strengthens the mechanisms that prevent these brain cells from firing.
The impact of physical activity on the ventral hippocampus specifically has not been deeply explored, said senior author Elizabeth Gould, Princeton's Dorman T. Warren Professor of Psychology. By doing so, members of Gould's laboratory pinpointed brain cells and regions important to anxiety regulation that may help scientists better understand and treat human anxiety disorders, she said.
From an evolutionary standpoint, the research also shows that the brain can be extremely adaptive and tailor its own processes to an organism's lifestyle or surroundings, Gould said. A higher likelihood of anxious behavior may have an adaptive advantage for less physically fit creatures. Anxiety often manifests itself in avoidant behavior and avoiding potentially dangerous situations would increase the likelihood of survival, particularly for those less capable of responding with a "fight or flight" reaction, she said.
"Understanding how the brain regulates anxious behavior gives us potential clues about helping people with anxiety disorders. It also tells us something about how the brain modifies itself to respond optimally to its own environment," said Gould, who also is a professor in the Princeton Neuroscience Institute.
The research was part of the graduate dissertation for first author Timothy Schoenfeld, now a postdoctoral fellow at the National Institute of Mental Health, as well as part of the senior thesis project of co-author Brian Hsueh, now an MD/Ph.D. student at Stanford University. The project also included co-authors Pedro Rada and Pedro Pieruzzini, both from the University of Los Andes in Venezuela.
For the experiments, one group of mice was given unlimited access to a running wheel and a second group had no running wheel. Natural runners, mice will dash up to 4 kilometers (about 2.5 miles) a night when given access to a running wheel, Gould said. After six weeks, the mice were exposed to cold water for a brief period of time.
The brains of active and sedentary mice behaved differently almost as soon as the stressor occurred, an analysis showed. In the neurons of sedentary mice only, the cold water spurred an increase in "immediate early genes," or short-lived genes that are rapidly turned on when a neuron fires. The lack of these genes in the neurons of active mice suggested that their brain cells did not immediately leap into an excited state in response to the stressor.
Instead, the brain in a runner mouse showed every sign of controlling its reaction to an extent not observed in the brain of a sedentary mouse. There was a boost of activity in inhibitory neurons that are known to keep excitable neurons in check. At the same time, neurons in these mice released more of the neurotransmitter gamma-aminobutyric acid, or GABA, which tamps down neural excitement. The protein that packages GABA into little travel pods known as vesicles for release into the synapse also was present in higher amounts in runners.
The anxiety-reducing effect of exercise was canceled out when the researchers blocked the GABA receptor that calms neuron activity in the ventral hippocampus. The researchers used the chemical bicuculine, which is used in medical research to block GABA receptors and simulate the cellular activity underlying epilepsy. In this case, when applied to the ventral hippocampus, the chemical blocked the mollifying effects of GABA in active mice.
Saturday, July 6, 2013
Latest Health Research
This is very good news for me because I get at least 200 minutes of exercise a week, but only exercise 2-3 days a week and am completely inactive the other days:
Total amount of exercise important, not frequency, research shows
Shorter Bouts of High-Intensity Exercise Improve Physical Fitness
Good news for me:
Aspirin for Primary Prevention in Men When Cancer Mortality Benefit Added
Farmed Salmon Raises Blood Levels of Omega-3s
Statin and Aspirin Use Linked to Improved Survival in Women with Endometrial Cancer
4 lifestyle changes will protect heart, reduce your risk of death
Healthy lifestyle choices mean fewer memory complaints
Coenzyme Q10 Improves Heart Failure Mortality
Consuming olive oil and nuts may improve survival men with prostate cancer
More good news - things I already do:
Fish oil supplements may protect the heart in stressful situations
Vitamin D Can Help Prevent Hypertension
Fatty acids found in fish linked to lower risk of breast cancer
Higher omega-3 fatty acids in blood = reduced risk of hip fractures
Aspirin may fight cancer by slowing DNA damage
And things I try to avoid:
Eating more red meat associated with increased risk of Type 2 diabetes
Soda and illegal drugs cause similar damage to teeth
Total amount of exercise important, not frequency, research shows
A new study by Queen’s University researchers has determined that adults who accumulated 150 minutes of exercise on a few days of the week were not any less healthy than adults who exercised more frequently throughout the week.
Shorter Bouts of High-Intensity Exercise Improve Physical Fitness
It is a commonly held perception that getting in shape and staying there requires hard work and hours upon hours of training. Now, new research from the Norwegian University of Science and Technology (NTNU) shows the opposite -- just four minutes of vigorous activity three times per week is enough to make previously inactive men fitter and more healthy.
Good news for me:
Aspirin for Primary Prevention in Men When Cancer Mortality Benefit Added
While aspirin has been shown to be effective in preventing heart attacks in men, it also increases the risk of gastrointestinal bleeding and possibly stroke, even at low doses. As such, national guidelines suggest that aspirin be used for prevention only in men at higher risk for cardiovascular events, so that the benefits of aspirin are greater than its adverse effects.
Recent data suggest that aspirin may also be effective for reducing cancer deaths. Would the possible combined health benefits of reducing heart attacks and cancer outweigh the risks of gastrointestinal bleeding and stroke for middle-aged men?
A research team, including UNC scientists, reports that including the positive effect of aspirin on cancer mortality influences the threshold for prescribing aspirin for primary prevention in men. The benefit of aspirin for cancer mortality prevention would help offset the risks and thus lower the age and increase the number of men for whom aspirin is recommended.
Farmed Salmon Raises Blood Levels of Omega-3s
People who eat farm-raised salmon can increase their intake of beneficial omega-3 fatty acids to levels that may help reduce their risk of heart disease, according to studies by U.S. Department of Agriculture (USDA) scientists.
The studies by Agricultural Research Service (ARS) nutritionist Susan Raatz and physiologist Matthew Picklo address concerns about whether farm-raised salmon have less available omega-3s than salmon caught in the wild. The scientists work at the ARS Grand Forks Human Nutrition Research Center in Grand Forks, N.D. ARS is USDA's principal intramural scientific research agency.
Two omega-3 fatty acids—EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid)—are abundant in oily fish such as salmon, tuna, mackerel, and herring. Consuming 250 milligrams daily of EPA and DHA—the amount in a 3-ounce farmed salmon fillet—has been associated with reduced heart disease risk.
Statin and Aspirin Use Linked to Improved Survival in Women with Endometrial Cancer
Endometrial cancer patients who took statins and aspirin reduced their chance of death by a highly significant 84 percent, according to a new study by researchers at Montefiore Einstein Center for Cancer Care. Additionally, women who used only statins saw their risk of dying decline by 45 percent.
4 lifestyle changes will protect heart, reduce your risk of death
A large, multi-center study led by Johns Hopkins researchers has found a significant link between lifestyle factors and heart health, adding even more evidence in support of regular exercise, eating a Mediterranean-style diet, keeping a normal weight and, most importantly, not smoking.
Healthy lifestyle choices mean fewer memory complaints
Research has shown that healthy eating, not smoking and exercising regularly are associated with a lower risk of Alzheimer's disease and dementia, but less is known about the potential link between positive lifestyle choices and milder memory complaints, especially those that occur earlier in life and could be the first indicators of later problems.
Coenzyme Q10 Improves Heart Failure Mortality
Coenzyme Q10 decreases all cause mortality by half, according to the results of a multicentre randomised double blind trial presented at Heart Failure 2013 congress. It is the first drug to improve heart failure mortality in over a decade and should be added to standard treatment, according to lead author Professor Svend Aage Mortensen (Copenhagen, Denmark).
Patients with ischaemic heart disease who use statins could also benefit from CoQ10 supplementation. Professor Mortensen said: "We have no controlled trials demonstrating that statin therapy plus CoQ10 improves mortality more than statins alone. But statins reduce CoQ10, and circulating CoQ10 prevents the oxidation of LDL effectively, so I think ischaemic patients should supplement statin therapy with CoQ10."
Consuming olive oil and nuts may improve survival men with prostate cancer
By substituting healthy vegetable fats – such as olive and canola oils, nuts, seeds and avocados – for animal fats and carbohydrates, men with the disease had a markedly lower risk of developing lethal prostate cancer and dying from other causes, according to the study.
More good news - things I already do:
Fish oil supplements may protect the heart in stressful situations
Vitamin D Can Help Prevent Hypertension
Fatty acids found in fish linked to lower risk of breast cancer
Higher omega-3 fatty acids in blood = reduced risk of hip fractures
Aspirin may fight cancer by slowing DNA damage
And things I try to avoid:
Eating more red meat associated with increased risk of Type 2 diabetes
Soda and illegal drugs cause similar damage to teeth
Addicted to soda? You may be shocked to learn that drinking large quantities of your favorite carbonated soda could be as damaging to your teeth as methamphetamine and crack cocaine use. The consumption of illegal drugs and abusive intake of soda can cause similar damage to your mouth through the process of tooth erosion.
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