A Canadian clinical trial that measured the effects of different types of meals on the inner lining of blood vessels in 28 nonsmoking men found that a meal loaded with saturated fats damages arteries. In contrast, a Mediterranean-style meal rich in good (mono- and polyunsaturated) fats caused no damage at all to blood vessels, and may even have had a beneficial effect. For the study, the men ate a meal composed of salmon, almonds, and vegetables cooked in olive oil. Arteries of the study participants dilated normally. The second meal included a sausage sandwich, an egg, cheese, and three hash browns. Arteries dilated 24 percent less than in the fasting state.
"Does the Adherence to a Mediterranean Diet Influence Baseline and Postprandial Endothelial Function?", Canadian Journal of Cardiology, October 30, 2012
Numerous studies have linked omega-3 fatty acids to a variety of health benefits. But a new U.S. clinical study found that 11 healthy young adults (ages 18 to 25) boosted their memory by increasing omega-3 intake. Participants in the study, which was not placebo-controlled, took an omega-3 fish oil supplement (FDA-approved Lovaza) daily for six months after various tests were performed, including brain imaging scans. At six months, participants underwent blood tests and completed working memory tests, including the “n-back test”. The working memory of the participants was shown to be greatly improved over pre-study results. The researchers were disappointed, however, that brain imaging tests did not reveal the mechanism of enhanced memory.
"Improved Working Memory but No Effect on Striatal Vesicular Monoamine Transporter Type 2 after Omega-3 Polyunsaturated Fatty Acid Supplementation", PLoS ONE, October 25, 2012
A comprehensive research review by Chinese and U.S. scientists has found that certain herbal and dietary supplements can be harmful when taken with prescription medications. The researchers analyzed 54 review articles and 31 original studies, finding particularly serious adverse effects when prescription drugs were taken with St. John’s Wort, magnesium, calcium, iron or ginkgo biloba. The greatest number of supplement interaction problems were with Warfarin, insulin, aspirin, digoxin and ticlopidine. Most of the interaction problems were caused by the supplements altering the way a drug is absorbed, distributed, metabolized and eliminated by the body.
"Evaluation of documented drug interactions and contraindications associated with herbs and dietary supplements: a systematic literature review", International Journal of Clinical Practice, October 24, 2012
The American Academy of Pediatrics has conducted an in-depth analysis of scientific evidence regarding the nutritional benefit of organic fruits and vegetables, finding that they have the same vitamins, minerals, antioxidants, etc., as conventionally grown produce – but without the pesticide residues. The AAP said that low pesticide levels could be a significant factor for young children. The researchers said no one really knows whether differences in pesticide levels have an adverse health impact over a lifetime, but "we do know that children – especially young children whose brains are developing – are uniquely vulnerable to chemical exposures."
"Organic Foods: Health and Environmental Advantages and Disadvantages", Pediatrics, October 22, 2012
Women whose diet is low in calcium run the risk of developing primary hyperparathyroidism (PHPT), a condition in which an overactive thyroid secretes too much parathyroid hormone, leading to weak bones, fractures and kidney stones, a study finds. U.S. researchers collected data beginning in 1986 on 58,354 women aged 39 to 66 years. They measured calcium intake from dietary sources and supplements every four years. Women with the highest intake of dietary calcium had a 44 percent lower risk of developing PHPT than those with the lowest intake. Even women who took a modest 500 mg/day of calcium supplements had a 59 percent lower risk than those who took no supplement.
"Calcium intake and risk of primary hyperparathyroidism in women: prospective cohort study", BMJ, October 18, 2012
Researchers in Sweden who tracked the dietary patterns of 32,561 women over ten years in a population-based cohort study found that total dietary antioxidant intake from fruits, vegetables, coffee, chocolate and whole grains, was important in the prevention of heart attack (myocardial infarction). A diet of fruits and vegetables rich in antioxidants reduced the risk of heart attack in women aged 49 to 83 by as much as 29 percent. The researchers acknowledged that the study was conducted among women and therefore could not be generalized to men.
"Total Antioxidant Capacity from Diet and Risk of Myocardial Infarction: A Prospective Cohort of Women", American Journal of Medicine, October 17, 2012
Taking a daily multivitamin seems to significantly reduce the risk of cancer in men, according to the results of the first long-term clinical trial on the impact of multivitamins on cancer. Researchers tracked nearly 15,000 men who took either a multivitamin or a placebo for more than 10 years. The men themselves reported whether they had been diagnosed with cancer. The researchers found that those who took a daily multivitamin had eight percent fewer cancer diagnoses compared with the group taking the placebo. The multivitamins were also associated with an apparent reduction in cancer deaths.
"Multivitamins in the Prevention of Cancer in Men: The Physicians' Health Study II Randomized Controlled Trial", JAMA, October 17, 2012
Mayo Clinic scientists who tracked 940 people aged 70 to 89 who provided regular information about their diets found that those who consumed a lot of carbohydrates were significantly more likely to experience mild cognitive impairment. The risk was even greater among those whose diet was heavy in sugar. Those who consumed a lot of protein and fat relative to carbohydrates were less likely to become cognitively impaired. At the start of the study participants showed no signs of cognitive impairment. But after four years 200 of those 940 were beginning to show mild cognitive impairment. When total fat and protein intake were taken into account, people with the highest carbohydrate intake were 3.6 times likelier to become cognitively impaired.
"Relative Intake of Macronutrients Impacts Risk of Mild Cognitive Impairment or Dementia", Journal of Alzheimer's Disease, October 16, 2012
A U.S. study in animals has found a connection between overeating and a brain malfunction associated with poor insulin control and eventually diabetes. Overeating impairs the ability of brain insulin to suppress glucose release from the liver and lipolysis in fat tissue. When a person overeats, the brain becomes unresponsive to important clues such as insulin, which then leads to diabetes. According to the researchers, the study shows “that it is really the brain that is harmed first [in overeating] which then starts the downward spiral."
"Short Term Voluntary Overfeeding Disrupts Brain Insulin Control of Adipose Tissue Lipolysis", Journal of Biological Chemistry, October 16, 2012
Children who have suffered from intestinal failure could benefit from adding the right prebiotics to their diet, a U.S. study has found in piglets. The researchers fed the newborn pigs the carbohydrate fructooligosacharide (FOS) as a prebiotic. Many premature infants develop necrotizing enterocolitis, a kind of gangrene of the intestine and have to be fed intravenously once the damaged parts of the intestine are surgically removed. The new research found that by adding FOS to the piglets’ diet, the gut grew and increased in function. FOS enters the intestines where bacteria convert it into butyrate, a short-chain fatty acid that increases the size of the intestines and their ability to digest and absorb nutrients.
" Intestinal Adaptation Is Stimulated by Partial Enteral Nutrition Supplemented With the Prebiotic Short-Chain Fructooligosaccharide in a Neonatal Intestinal Failure Piglet Model", Journal of Parenteral and Enteral Nutrition, October 15, 2012
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Pediatrics, October 22, 2012
News release, presentations at the annual meeting of the Society For NeuroScience, October 16, 2012
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