News Briefs – April 2011

MODERATE AEROBIC EXERCISE LINKED TO IMPROVED MEMORY

Researchers have found an association between moderate levels of aerobic exercise and increased size of the hippocampus, an area of the brain involved in memory. This is the first study to focus on older adults who already have experienced some decrease in the size of the hippocampus, believed to be the (potentially-inevitable) cause of memory loss with age. Some of the 120 sedentary adults in the study were placed on a routine of brisk, 40-minute walks three times a week, while others did stretching and toning exercises. In those who walked, hippocampus size increased almost 2%; memory function improved; levels of brain-derived neurotrophic factor (a biomarker for learning and memory) increased; and scores on spatial memory tests were higher. (Spatial memory records information about a person’s immediate environment and geographical orientation.) It is important to note that the effect was found only with aerobic exercise; and that only moderate exercise levels were sufficient to produce this effect. This study was released January 31, 2011 but will not appear in print until a future issue of the journal, Proceedings of the National Academy of Sciences. It is available online now at https://bit.ly/hhnodP with subscription or fee.

BERRY CONSUMPTION MAY REDUCE PARKINSON’S RISK

The first-ever study on the link between flavonoids and Parkinson’s disease has found a lower risk of developing the disease among men and women who regularly eat berries. The study also found that – among men – the risk of Parkinson’s is reduced even further by the regular consumption of apples, oranges and other dietary sources of flavonoids. (Flavonoids are found in plants and fruits; and in cocoa, tea and red wine. Parkinson’s is a degenerative disease of the central nervous system.) The research drew information from over 129,000 people by questionnaire and found that males who were in the top 20% of flavonoid consumers had a 40% lower risk of the disease, compared to those in the bottom 20%; there was no lower risk for women with higher overall flavonoid intake. However, when specific flavonoids were analyzed, it became clear that men and women alike enjoyed a lower risk of Parkinson’s with the type of flavonoids called anthocyanins, which are mainly obtained from berries. This study was released February 14, 2011 but details will not be available until the 63rd annual meeting of the American Academy of Neurology in April.

WORLD HEALTH ORGANIZATION ISSUES EXERCISE RECOMMENDATIONS TO FIGHT CANCER

The World Health Organization (WHO) has issued new, global, exercise recommendations aimed at reducing the risk of breast cancer and colon cancers. While various types of cancer might be prevented by exercise, WHO experts estimate, after examining the scientific evidence, that 25% of breast and colon cancers could be prevented if sedentary people exercised just 150 minutes a week. The WHO stressed that this amount of exercise could be attained easily with a moderately brisk, 30-minute walk on five days of the week. The WHO reports that 31% of the world’s population is inactive, the fourth leading risk factor globally for death. One person in two will have a cancer in his or her lifetime, and the risk increases with age. The WHO released the new anti-cancer recommendations in time for World Cancer Day, which was February 4, 2011.

INSUFFICIENT SLEEP INCREASES RISK OF STROKE AND HEART ATTACK

Researchers have concluded that chronically getting less than six hours of sleep a night produces hormones and chemicals in the body that are associated with greater risks of developing high blood pressure, elevated cholesterol, heart attacks, strokes, cardiovascular disease, diabetes and obesity. In fact, regularly sleeping less than six hours a night can result in a 48% higher risk of developing or dying of heart disease and a 15% greater risk of developing or dying of a stroke. Sleeping over nine hours a night has been linked to illness, including cardiovascular disease. It is the chronic lack of sufficient sleep that produces long-term risk, not an occasional late night and early morning. The study analyzed data from 470,000 participants from eight countries. This study was released online February 8, 2011 by the European Heart Journal and will appear in a future print issue.

CHAMOMILE TEA STUDY

Drinking chamomile tea daily with meals may help prevent the complications of diabetes, which include loss of vision, nerve damage and kidney damage. This possibility was raised when chamomile extract was fed to diabetic rats and it lowered levels of two substances associated with increased diabetic complications. Researchers reported this study in the September 10, 2008 issue of the Journal of Agricultural and Food Chemistry.

WHY FOLIC ACID PREVENTS FIRST HEART ATTACK – BUT NOT SECOND

New research explains why folic acid supplements help prevent a first heart attack but has failed in studies to show benefit in preventing a second occurrence. The B vitamin, folic acid, lowers homocysteine in the blood, an effect linked to a reduced heart attack risk. Yet providing folic acid to heart patients has failed to lower the risk of a second attack.

Analysis of 75 studies involving about 50,000 people, and clinical trials involving about 40,000 people, showed that heart patients often are placed on aspirin therapy. Aspirin reduced homocysteine levels, which means patients received no extra benefit from the folic acid. Folic acid taken by those who have not yet suffered a heart attack (and therefore, are not yet on aspirin therapy) lowered homocysteine levels and helped prevent attacks. This suggests folic acid supplements may be an effective replacement for aspirin, which can involve side effects (bleeding ulcers, asthma attacks, Reye’s syndrome), and thus help prevent both first and subsequent attacks. This study, released February 2, 2011, will not appear in print until a future issue of the American Journal of Clinical Nutrition. It is available online now at https://bit.ly/h1KRu without charge.

LIFESTYLE CHANGES TREAT SPECTRUM OF MENTAL HEALTH PROBLEMS

Researchers report that a number of therapeutic lifestyle changes (TLCs) have the generally unrecognized ability to treat schizophrenia, depression, anxiety, panic attacks, insomnia, stress, cognitive decline, age-related memory loss, other mental and emotional problems – and even help prevent strokes and the common cold – sometimes as effectively as drug therapy (with fewer complications) or psychotherapy. The complete TLC list includes: exercise (boosts cognitive performance and reduces memory loss); a diet rich in fruits, vegetables and fish (improves cognitive function and reduces affective and schizophrenic symptoms); spending time in nature (promotes cognitive function and well-being); maintaining good, social relationships (reduces many risks, from colds to strokes to mental illness); pursuing recreation and fun (reduces defensiveness and fosters social skills); relaxation and stress management (treats numerous anxiety, insomnia and panic disorders); meditation (boosts empathy, emotional stability, cognitive function and brain size); being religiously or spiritually involved (can reduce anxiety, depression and substance abuse); and providing a service to others (promotes mental and physical health and may extend lifespan). This study was released February 17, 2011 by American Psychologist but will not appear in the journal until a future issue. It is available at https://bit.ly/hvlDlc for a fee.

INFECTIONS FROM SLEEPING WITH PETS ARE RARE

A study has found that, although humans can contract serious infections from pets if they sleep under the covers with their dogs or cats or exchange kisses with them, these incidences are extremely rare. Pets bring infectious agents into the household but transmission between pets and humans requires close contact, especially licking or kissing, often coupled with a weakened immune system, reported the researchers. Vaccinated pets pose far less risk; and hand-washing, especially before meals, affords excellent protection. Even a pet with fleas seldom infects its owners. Previous studies found that pets bring psychological support, stress-relief and healthier habits such as walking; that growing up with pets lowers the risk of autoimmune disorders; and that petting animals increases levels of oxytocin, a feel-good hormone, and lowers levels of the stress-causing hormone cortisol. The new study was reported in a recent issue of Emerging Infectious Diseases, the journal of the Centers Disease Control. If you’d like the benefits of pet care without the commitment of ownership, some no-kill agencies seek volunteers to give threatened street orphans a temporary home. One is Toronto Cat Rescue at https://bit.ly/ fxp70W

EAR INFECTIONS

It is a myth that ear infections are a symptom or result of the common cold. All colds are caused by viruses, while 90% of ear infections are caused by bacteria. The reason this myth appears to be valid is that colds create mucous and fluid buildup in the ear tubes. This fluid is an ideal environment for bacteria to take up residence.

ANIMAL FAT AND PROTEIN LINKED TO DIABETES

People who adhere long-term to a diet low in carbohydrates and high in protein and fat can get the fat-and-protein portion of their diet from animal sources or vegetable sources. Researchers have found that those low-carbohydrate dieters who get their fat and protein primarily from animal sources have a 37% greater risk of developing type 2 diabetes. Generally, there was no greater risk of diabetes 2 among low-carb dieters with a high intake of vegetable-sourced protein and fat; in fact, there was a 22% lower diabetes risk among those in this group who were over age 65. The finding in this 20-year study of 40,475 diabetes-free individuals held true even after allowing for various other factors such as age, smoking, physical activity, coffee intake, alcohol intake, family history of T2D, total energy intake, and body mass index. The researchers suggested that low-carb dieters get their protein and fat from foods other than red and processed meat. Released February 10, 2011 by the American Journal of Clinical Nutrition, this study will not appear in print until a future issue.

AGING AND VITAMIN B12

Older people with lower-than-average blood levels of vitamin B12 are six times more likely to experience brain shrinkage, which has been linked to the risk of developing dementia. This was the finding of a study in the September 9, 2008 edition of the journal Neurology. Many foods are now fortified with folic acid, which can mask vitamin B12 deficiency in older adults. Vitamin B12 is found in meat, fish and supplements.

HIGHER VITAMIN D INTAKE MAY PREVENT CANCER, MS

Scientists studying people taking vitamin D supplements ranging from 1,000 to 10,000 international units (IU) daily, have concluded that intakes much higher than currently recommended levels are required to maintain blood concentrations that could cut the risk of some cancers by about 50%. Circulating levels of the 25(OH)D form of this vitamin are what count; and the team found that intakes of 4,000 to 8,000 IU of vitamin D a day are needed to maintain sufficient blood levels of this form of the vitamin to reduce by half the risks of breast cancer, colon cancer, diabetes 1 and multiple sclerosis (MS). However, on November 30, 2010, the U.S. National Academy of Sciences Institute of Medicine committee recommended a minimum daily intake of only 600 IU and an upper tolerable limit of 4,000 IU daily for those over age eight. Those considering vitamin D supplements should consult their health practitioner, especially if pregnant or breastfeeding, or considering supplements for children; vitamin D derived from sun exposure does not produce toxicity. This study was published in the Feb. 21, 2011 issue of Anticancer Research.

DID YOU KNOW…?

Romantic dinners could be good for your health. All you have to do is skip the champagne and oysters and opt for red wine and dark chocolate. Both red wine, and dark chocolate with a cocoa content of 70% or more, contain resveratrol, which lowers blood sugar and is linked to good health; and potent antioxidants called phenols, which prevent the buildup of plaque in the arteries. Red wine also provides catechins, which raise HDL (good) cholesterol.

ANTI-FUNGAL COMPOUNDS USED BY SEAWEED MAY FIGHT MALARIA

Researchers have discovered new compounds on the surface of seaweed (several dozens in a single species) that fight off attacks by fungus and that, initially, show some ability to fight malaria. The team discovered these compounds – known collectively as bromophycolides, in light-colored patches on the seaweed species Callophycus serratus – using a new analytical technique called desorption electrospray ionization mass spectrometry (DESI-MS). The compounds gather at the site of injury, apparently to fight fungal infection. The key molecule in these compounds showed promising activity against malaria and the next step will be testing on rodents. (Malaria, a disease killing a million people annually, is caused by a parasite that has developed resistance to most drugs. Seaweeds are a form of algae.) This study was presented on February 21, 2011, at the annual meeting of the American Association for the Advancement of Science (AAAS) in Washington, D.C.

STUDY CONFIRMS ABSENCE OF MICROBES AS CAUSE OF ASTHMA

Studies over the years have shown that children living on farms are significantly less likely to develop asthma than other children living in the same area; and researchers have hypothesized that exposure on farms to a wider diversity of bacteria may be protective against asthma. A large, new study has confirmed this hypothesis. Also, the research team identified specific species of bacilli, staphylococci and fungi that may be responsible for this protective benefit. The mechanism by which these bugs prevent asthma is far from established. (However, long-standing theory suggests that exposure to more microbes early in childhood when the immune system is developing teaches the body not to overreact later in life when these bacteria are encountered. Asthma, hay fever and numerous other autoimmune disorders are theorized to be an immune overreaction to harmless agents.) Microbial diversity alone may not be enough to prevent asthma; it may require species in a particular combination, which future studies could pinpoint. This study was released February 24, 2011 and will be published in a future issue of the New England Journal of Medicine

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GREEN TEA STUDY

Drinking green tea, which is packed with polyphenols, may reduce the risk Alzheimer’s disease and other forms of dementia, according to a study released December 22, 2010 by the journal Phytomedicine. The study was the first to show that the protective effect is still active after the tea has been digested. Green tea also may protect brain cells against Parkinson’s disease, reported a study in the December 15, 2007 issue of Biological Psychology. And in a study published October, 2010 in the FASEB journal, green tea was shown to impede the growth of the cells of at least some cancers.