News Briefs – November 2009

High-Fat Diets Damage Muscle

A new Canadian study on mice suggests that high-fat diets significantly impair skeletal muscle – long before other pre-diabetic changes appear, such as insulin resistance, weight gain and greater fat mass. Initially, these high-fat diets don’t diminish muscle strength. But soon, some muscles alter fibre type, while others change fibre size. And in all cases, high-fat diets decreased the ability of skeletal muscle to use fat or glucose as fuel. The McMaster University team in Hamilton, Ont., published the research in the Oct. 6, 2009 issue of PLoS One (a journal of the Public Library of Science).

In a separate U.S. study, just published at the website of the Journal of the National Cancer Institute, a high intake of dietary fats from red meat and dairy products was associated with an increased risk of pancreatic cancer. Half a million people were surveyed. Men and women who consumed high amounts of total fats had 53% and 23% higher relative rates of pancreatic cancer, respectively, compared with men and women who had the lowest fat consumption. Participants consuming high amounts of saturated fats, specifically, had 36% higher relative rates of pancreatic cancer compared with those who consumed low amounts. The research was done at the Division of Cancer Epidemiology and Genetics at the National Cancer Institute in Bethesda.

Mediterranean Diet Reduces Depression Risk

A new, multi-university, Spanish survey of 10,094 people suggests that those who adhere to the Mediterranean diet are 30% less likely to develop depression. Olive oil boosts the anti-depression brain chemical, serotonin. But the lower depression risk may stem from the synergistic combination of all dietary components. The Mediterranean diet includes a high ratio of monounsaturated fats to saturated fats, moderate alcohol and dairy, a low intake of meat, and a high intake of fish, legumes, fruits, nuts, cereals and vegetables. The Archives of General Psychiatry published the study in its October 2009 issue.

Omega-3 Oil May Prevent Blindness

Maryland research suggests that higher levels of an oil found in fatty fish or fish oil supplements helps prevent both types of a leading cause of blindness, called age-related macular degeneration (AMD). The study followed 1,837 persons at moderate-to-high risk of this condition from progression to advanced AMD. Participants reporting the highest consumption of omega-3 oil (omega-3 long-chain polyunsaturated fatty acids) – about 0.11 per cent of total calories – showed a 30% lower risk of AMD. The study appears in an upcoming issue of the American Journal of Clinical Nutrition but was posted online Oct. 7, 2009.

Exercise Extends Life for Kidney Patients

A Utah study found exercise means longer lives for chronic kidney disease (CKD) patients. CKD can inhibit exercise and many patients die prematurely for reasons not related directly to the disease. Scientists wondered if exercise could offer CKD patients the same benefits as non-CKD patients.

Active patients were found to be 56% less likely to die during the study than inactive patients. The Clinical Journal of the American Society of Nephrology posted the study on its website on Oct. 9, 2009.

Weight Training Slows Muscle Breakdown

Weight training may “rejuvenate” muscle blood flow and therefore help retain muscles in older people. In one study, three weight training sessions per week over 20 weeks rejuvenated blood flow in the extremities to the point that it was identical to the blood flow in the younger group. Suppression of muscle breakdown is blunted with age, which may explain the ongoing loss of muscle in older people – when they eat they don’t build enough muscle, and in addition, their insulin fails to shut down the muscle breakdown that rises between meals and overnight. But weight training may help offset this age-related muscle breakdown. The study appears in the September 2009 issue of the American Journal of Clinical Nutrition.

‘Safe’ Lead Levels Hamper Brain Development

Lead pollution in the environment remains a health hazard for children. Research released on Sept. 17, 2009 in the Archives of Disease in Childhood, reveals that blood lead concentrations well below the accepted “safe” level harm youngsters’ intellectual and emotional development. A study at University of Bristol in the U.K. measured blood lead levels in 488 children at age 2, and linked these levels to scores on standardized assessment tests between ages 7 and 8. There was a clear link between blood lead levels in early childhood and academic performance by the ages of 7 and 8, the researchers reported.

Children with blood lead levels between 2 and 5 micrograms per decilitre performed significantly better on standardized tests than those with blood lead levels above 5 micrograms per decilitre, they found. Blood lead levels between 5 and 10 micrograms per decilitre were associated with significantly poorer scores for reading – 49% lower; and for writing – 51% lower. Currently, the internationally accepted “safe” threshold of blood lead is 10 micrograms per decilitre, but Alan Emond, PhD, who led the current study, is now calling for this figure to be halved to just 5 micrograms per decilitre based on his team’s findings.

“Exposure to lead early in childhood has effects on subsequent educational attainment, even at so-called low blood levels of 5 to 10 micrograms per decilitre,” Emond noted in an email to News Briefs. “Our results suggest that the threshold for clinical concern should be reduced to 5 micrograms per decilitre.” The researchers also talked to teachers as part of their research and found that children with blood lead levels above 10 micrograms per decilitre were nearly three times as likely to show hyperactivity and anti-social behaviour as children whose blood lead levels were between 0 and 2 micrograms per decilitre, the opposite extreme.

Creatine Increases Endurance, Power

Recreationally active men using supplemental creatine during high-intensity interval training showed significant improvement in maximal power output that could be maintained without fatigue, the September 2009 issue of the Strength and Conditioning Journal reported. Participants who supplemented with 10 grams of creatine showed a 6.7% increase in critical power over six weeks. High-intensity interval training, the study pointed out, has been shown to be highly effective in improving endurance, including optimal oxygen intake. Participants rode cycle ergometers.

NEWS NOTES

· Chinese herbs may control blood sugar: A literary review that examined 16 clinical trials of 15 different herbal formulations found that the Chinese herbs generally helped lower blood sugar levels in people with “pre-diabetes” – those with impaired blood-sugar control that can progress to full-blown Type 2 diabetes. The herbs used were “Chinese herbal mixes traditionally used for blood-sugar control,” including products such as Jiangtang Bushen, Xiaoke huaya and Tang Kang yin. The study appeared in the Oct. 14, 2009 issue of the Cochrane Library, which is published by the Cochrane Collaboration, an international organization that evaluates medical research.

· Vanadium supplements for diabetes: In the Oct. 20, 2009 issue of the Cochrane Library, researchers recently published a systematic review of the supplement vanadium for diabetes. Laboratory studies have shown that vanadium acts in similar ways to insulin when added to various tissues. When some animals were given vanadium supplements, their blood sugar levels were lowered, which is a beneficial effect related to diabetes.

· Green tea fights some blood cancers: Drinking green tea may lower your risk of developing certain blood cancers, but it will take about five cups a day, according to a study from Japan. The study appears in the October 2009 issue of the American Journal of Epidemiology.

· Probiotics for eczema: Treating pregnant mothers, and then their infants, with select strains of probiotics may help prevent a skin condition known as eczema in children with a family history of allergies, particularly during the first three months of life, Dutch researchers report. Probiotics are bacteria present naturally in the body and sometimes added to food or dietary supplements to boost immune function. The study was published in the Oct. 13, 2009 issue of the journal Allergy.

· Antioxidants cut premature birth risk: Pregnant women who eat plenty of red- and orange-hued fruits and vegetables may have lower odds of giving birth prematurely, a new study suggests. Researchers found that among more than 5,300 women who gave birth at one of four Canadian hospitals, those with higher blood levels of certain carotenoids were less likely to deliver pre-term. Carotenoids are pigments that give yellow, orange, and red hues to a variety of fruits and vegetables, such as tomatoes, carrots, red peppers, watermelon, oranges and orange juice. They also act as antioxidants, meaning that they help protect body cells from damage that can lead to disease. The research was published in the September 2009 issue of the journal Epidemiology.

· Active kids fall asleep faster: If you’ve always thought children who wear themselves out during the day sleep better, research now backs you up. For every hour a child spends each day being sedentary, it takes three minutes longer to get to sleep, suggests a new study from New Zealand, reported in the September 2009 issue of the Archives of Disease in Childhood. And the more activity a child gets, the faster he falls to sleep. The study’s findings emphasize that physical activity is important not only for fitness, heart health and weight control, but for good sleep.

· Women show same heart attack symptoms: It’s a myth that women and men exhibit different symptoms when suffering a heart attack, says a study presented at the Canadian Cardio-vascular Congress on Oct. 25, 2009. Researchers found no gender differences in symptoms after studying 305 patients undergoing angioplasty. They say it is a commonly held belief that men and women feel the effects of a heart attack differently. In the study, researchers found that women had all the classic symptoms such as chest pain, and tended to have pain in the throat, jaw and neck. The first thing most people feel is heaviness in the chest.

· White wine bad for enamel: Enjoying a glass of white wine on a frequent basis can damage the teeth by eroding the enamel, German researchers warn. Pale plonk packs an acidic punch that erodes enamel far more than red wine, the Oct. 20, 2009 edition of Nutrition Research reports. It’s the pH balance and length of time contacting teeth. Eating cheese at the same time could counter the effects, because it is rich in calcium, the German authors wrote.

· Stress no longer excuse for junk food: During times of stress, many people will reach for that favourite bag of chips, soft drink or snack cake for a dose of quick comfort – or so conventional wisdom holds. But, a new study from the University of South Carolina takes aim at that comfort-food theory and contends that people undergoing significant change in their lives often pick unfamiliar, even healthier foods and lifestyle options. The research, titled “The Comfort Food Fallacy: Avoiding Old Favorites in Times of Change,” was published in the October 2009 issue of the Journal of Consumer Research.

HEALTH NOTES

Can’t Lose Weight?  Blame Your Body

Blame your body if your diet starts successfully but then crashes and burns, or if you can’t keep the weight off, no matter how hard you try. Then, train your body to stop craving food and feel full sooner, says Louis Aronne, PhD, in his new book, The Skinny: On Losing Weight Without Being Hungry (Broadway Books), written with Alisa Bowman. Aronne contends that diets stumble because of the body’s chemistry, not willpower. His simple plan could drop your weight by between 10 and 20% of your weight.

“If you don’t first re-sensitize your weight-regulation mechanisms, typical approaches to weight loss, such as portion control and calorie counting, just won’t work,” explains Aronne. Human bodies are programmed to resist weight loss that goes beyond roughly seven per cent of total body weight and that means if you weigh 200 pounds, you may be able to lose fewer than 14 pounds before the going gets tough. The reason is that the body’s metabolism and weight-regulating hormones, such as insulin and leptin, drop faster than your body loses fat, making your brain think your weight is near normal even though you’re still overweight. This leaves dieters hungry, even after they’ve eaten all the calories they need.

To overcome this obstacle, flip off the internal biological switch that is driving you to eat. Among his specific tips: (1) Eat a protein breakfast. People who eat breakfast are more successful at losing weight because it helps control appetite and cravings throughout the day. Avoid juices – they pass through the body too quickly – opt for real fruit. (2) Exercise in the morning and how often is more important than how long. (3) Eat vegetables, salads and soups first, and shoot for some spicy foods. (4) Watch less television. (5) Sleep disorders and medications can cause weight gain – watch for these diet-enemies. Also, we remind you to take supplements to keep your nutrient intake high while your food intake is dropping.

Folic Acid Lowers Hearing Loss Risk

New research has found that men over 60 with high intakes of folate can reduce – by a full 20% – their risk of developing hearing loss, America’s most common sensory disorder. (Antioxidant vitamins showed no hearing benefit.) Folate-rich foods include leafy vegetables, legumes, yeast, liver and a few other fruits and vegetables.

Folic acid is the synthetic form of folate found in supplements. Scientists presented the study at the 2009 annual meeting and expo of the American Academy of Otolaryngology-Head and Neck Surgery Foundation (AAO-HNSF), which wrapped up October 7 in San Diego, California.

Particular Bacterium May Fight Colitis

A new study on mice has shown that a bacterium, known as Bacillus polyfermenticus, has a distinct, protective effect against colon inflammation – the condition known as colitis. Although this bacterium has other health benefits, this research looked only at colitis. Mice with colitis that were given B. polyfermenticus had far less severe symptoms, which can include weight loss, diarrhea and mucosal (colon lining) damage.

Inflammatory molecule production was decreased in the colon and anti-inflammatory molecule production was increased. Also, beneficial cells were produced. The October 2009 issue of the Journal of Nutrition published the findings.

Strawberries Lower Cholesterol

An Oklahoma study has concluded that a strawberry-based beverage can lower cholesterol levels very quickly – including the “bad” cholesterol, LDL – in women with metabolic syndrome. (Metabolic syndrome includes unfavourable cholesterol readings, poor glucose tolerance, high blood pressure and mid-section obesity.)

Subjects consumed two cups of the strawberry drink twice a day for just four weeks. Each cup contained 25 grams of frozen strawberry powder, blended in water. It is unclear if the benefit comes from one or several components: the antioxidants, fibre or phytochemicals in the strawberries. The October 2009 issue of Nutrition Journal published the research.