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U.S. researchers have found that digestive exposure to nanoparticles of polystyrene influences the absorption of the important nutrient iron into the bloodstream. Nanoparticles are contained in many substances, from cosmetics and clothes, to soda and snacks. For brief exposures to polystyrene particles, iron absorption dropped by 50 percent. But when exposure to nanoparticles was significantly increased, absorption of iron increased by about 200 percent. “It was very clear,” the researchers concluded, “nanoparticles definitely affect iron uptake and transport." The researchers hope to test whether nanoparticles also disrupt absorption of calcium, copper and zinc, as well as fat-soluble vitamins A, D, E and K.
"Oral exposure to polystyrene nanoparticles affects iron absorption", Nature Nanotechnology, March 08, 2012
A U.S. researcher who analyzed data from a variety of weight loss studies has concluded that no evidence exists that any single product results in significant weight loss, and many can be harmful. The researcher looked at studies involving four main categories of products: chitosan, which block absorption of fat or carbs; stimulants such as caffeine or ephedra that increase metabolism; products such as conjugated linoleic acid that claim to decrease body fat; and appetite suppressants such as soluble fibers. “For most people, unless you alter your diet and get daily exercise, no supplement is going to have a big impact,” the researcher said.
"Dietary Supplements for Improving Body Composition and Reducing Body Weight: Where is the evidence?", International Journal of Sport Nutrition and Exercise Metabolism, March 06, 2012
A seven-year U.S. study of preadolescent and adolescent girls has discovered a link between vitamin D intake levels and a lower risk of developing stress fractures, especially among girls active in high-impact activities. The researchers found no lessening of stress fracture risk linked with calcium intake, however, despite that fact that consumption of calcium and calcium-rich dairy products is routinely recommended for optimal bone health. They also noted that their findings support the Institute of Medicine's recent increase in the recommended dietary allowance for vitamin D for adolescents from 400 IU/d to 600 IU/d.
"Vitamin D, Calcium, and Dairy Intakes and Stress Fractures Among Female Adolescents", Archives of Pediatrics & Adolescent Medicine, March 05, 2012
A clinical study involving five critically ill heart patients with diabetes found that treatment with a flavonoid (epicatechin) contained in dark chocolate improved cell mitochondrial structure and boosted the ability to exercise. Mitochondria are cell structures responsible for energy production. Both type 2 diabetes and heart failure make mitochondria dysfunctional, causing muscle abnormalities. Trial participants ate dark chocolate bars and a beverage with a total epicatechin content of 100 mg a day for three months. The positive results of the small trial provided enough evidence to launch a larger, placebo-controlled clinical trial at UC, San Diego.
"Alterations in Skeletal Muscle Indicators of Mitochondrial Structure and Biogenesis in Patients with Type 2 Diabetes and Heart Failure: Effects of Epicatechin Rich Cocoa", Clinical and Translational Science, March 02, 2012
Healthy people in their twenties who were able to maintain a healthy lifestyle into their forties – lean body mass index, moderate alcohol intake, no smoking, healthy diet and regular exercise – kept their risk of cardiovascular disease low in middle age, according to a U.S. study. Researchers analyzed 20 years of data on key lifestyle factors from more than 3,000 participants in a national study. In the first year of the study (1985, average age 24 years), 44 percent had a low cardiovascular disease risk profile. Twenty years later, only 24.5 percent fell into the low cardiovascular disease risk category. The increased risk of the others was due to unhealthy diets, weight gain, smoking, etc., all of which combined to increase blood pressure, cholesterol and diabetes.
"Healthy Lifestyle Through Young Adulthood and the Presence of Low Cardiovascular Disease Risk Profile in Middle Age: The Coronary Artery Risk Development in (Young) Adults (CARDIA) Study", Circulation, March 02, 2012
Autistic children may experience improvements in social behavior and physiological symptoms if they stick to a gluten-free, casein-free diet, U.S. researchers have found. Gluten and casein are both proteins, the former found in wheat flour and the latter in cow’s milk. For the study, 387 parents of autistic children reported on how much gluten and casein their kids consumed. The researchers found that a gluten-free, casein-free diet among children with gastrointestinal and allergy problems was effective in improving social behaviors, such as language production, eye contact, engagement, attention span, requesting behavior and social responsiveness.
"Effectiveness of the gluten-free, casein-free diet for children diagnosed with autism spectrum disorder: Based on parental report", Nutritional Neuroscience, February 29, 2012
A U.S. study of 1,575 dementia-free people whose average age was 67 found that those with lower levels of omega-3 fatty acids in their blood had lower brain volumes – equivalent to about two years worth of structural brain aging. Those whose omega-3 levels were among the bottom 25 percent of participants had lower brain volume compared to those who had higher omega-3 levels. In addition, those with the lowest levels of omega-3s also scored lower on tests of visual memory and executive function, such as problem solving, multi-tasking and abstract thinking.
"Red blood cell omega-3 fatty acid levels and markers of accelerated brain aging", Neurology, February 27, 2012
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Evidence-Based Complementary and Alternative Medicine, March 05, 2012
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