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Not all people who enjoy a glass of wine each day can expect a cardio-protective effect from the drink, according to Canadian and German researchers who conducted a meta-analysis of 44 studies involving nearly a million people and 38,627 ischemic heart disease events, including death. The researchers found that the protective effect can vary by sex, drinking patterns, and other health factors. Alcohol consumption can also be detrimental in the presence of other health problems, such as cancer. “Any advice by physicians on individual drinking has to take the individual risk constellation … into consideration,” the researchers said.
"The cardioprotective association of average alcohol consumption and ischemic heart disease: a systematic review and meta-analysis", Addiction, January 30, 2012
Reducing the amount of protein or amino acids consumed before surgery can reduce the possibility of dangerous complications such as heart attack or stroke, a U.S. study has found. For the study, two groups of mice were fed either a normal diet or one lacking certain amino acids for two weeks. Both groups were then subjected to surgical stress that affected the kidneys or liver. Forty percent of the mice that ate the normal diet died after the surgery; all of the protein-restricted mice survived. The researchers said the results are significant because they isolate protein as an important substance to eliminate from the diet before surgery to avoid complications.
"Surgical Stress Resistance Induced by Single Amino Acid Deprivation Requires Gcn2 in Mice", Science Translational Medicine, January 25, 2012
A U.S. study has found that women who reduce the number of calories consumed from animal fat and cholesterol before pregnancy can reduce the risk of gestational diabetes, a condition potentially harmful to both expectant mothers and infants. The study also found that the increased risk of gestational diabetes was independent of other dietary and non-dietary risk factors. For example, women who exercised but ate larger amounts of animal fat and cholesterol did not reduce the risk of gestational diabetes. Diets high in total fat or other kinds of fats -- but not in animal fat or cholesterol -- did not increase the risk, the study found.
"A prospective study of prepregnancy dietary fat intake and risk of gestational diabetes", American Journal of Clinical Nutrition, January 25, 2012
A U.S. study of 559 teenagers found a significant association between high-fructose diets and higher blood pressure, fasting blood glucose levels, insulin resistance and inflammatory factors that contribute to cardiovascular disease. Participants in the study were also found to have lower levels of cardiovascular protectors such as HDL cholesterol and the protein adiponectin. According to the researchers, the fructose in high fructose corn syrup is pretty much the same as in table sugar, “but it's believed there's something in the syrup processing that plays a role in the bad byproducts of metabolism."
"Greater Fructose Consumption Is Associated with Cardiometabolic Risk Markers and Visceral Adiposity in Adolescents", Journal of Nutrition, January 24, 2012
School-based childhood obesity programs may be having an unintended harmful effect on some kids, according to a poll of American parents. Nearly a third of parents of children ages 6 to 14 who were surveyed about obesity prevention programs in their schools said their kids were engaged in “worrisome behavior”: inappropriate dieting, excessive worry about fats in foods, preoccupation with food content and labels, refusing family meals, and too much physical activity. Eighty-two percent of parents reported at least one obesity intervention program in their child’s schools. Seven percent said their children were made to feel bad at school about what and how much they were eating.
"School Obesity Programs May Promote Worrisome Eating Behaviors and Physical Activity in Kids", National Poll on Children's Health, January 24, 2012
Spanish researchers report that in their country, where foods are fried in olive oil or sunflower oil, they observed no association between consumption of fried foods and the risk of coronary heart disease or premature death. The authors stress that their findings may not apply to other countries, where solid and re-used oils are often used for frying. The researchers surveyed the cooking methods of nearly 41,000 heart disease-free adults ages 29 to 69 years over 11 years. An accompanying editorial says that the study explodes the myth that "frying food is generally bad for the heart" but emphasizes that specific aspects of frying food are relevant, such as the type of oil used.
"Consumption of fried foods and risk of coronary heart disease: Spanish cohort of the European Prospective Investigation into Cancer and Nutrition study", BMJ, January 24, 2012
Though it has been the prevailing wisdom for four decades, a U.S. study finds that eating a high-fiber diet does not reduce the risk of diverticulosis – pouch formation – in the large intestine. In fact, consuming a diet high in fiber seems to increase the risk of diverticulosis, which affects a third of adults over age 60 and can be harmful if complications develop. The study was based on data from 2,104 patients aged 30-80 years who underwent outpatient colonoscopy from 1998-2010. "We were surprised to find that a low-fiber diet was not associated with a higher prevalence of asymptomatic diverticulosis," one researcher said.
"A High-Fiber Diet Does Not Protect Against Asymptomatic Diverticulosis", Gastroenterology, January 23, 2012
German researchers have confirmed a fact that most people already knew: pictures of delicious food trigger hunger pangs. The study, which was conducted among healthy young men, suggests that the pervasive presence of pictures of appetizing food in the media contributes to weight increase in Western populations. The researchers showed the study participants picture of food, then measured the amount of the neurosecretory protein hormone ghrelin in the blood. They found that the level of ghrelin, which controls both eating behavior and physical processes involved in food metabolism, increased significantly as a result of visual stimulation from food images.
"Ghrelin Levels Increase After Pictures Showing Food", Obesity, January 19, 2012
Swiss and U.S. researchers have discovered that limiting the effect of a molecule called NcoR that adjusts metabolism much like a dimmer switch adjusts electric flow could provide a way to ramp up metabolism and reduce the risk of obesity and diabetes. According to the researchers, it might be possible to produce drugs that specifically target NCoR activity only in one tissue or another, such as fat or muscle. "With this adipocyte [NCoR] knockout you get systemic insulin sensitivity; the liver and muscle gets better too," the researchers concluded. "At the end of the day, it's doing something good for metabolism."
"Adipocyte NCoR Knockout Decreases PPARγ Phosphorylation and Enhances PPARγ Activity and Insulin Sensitivity", Cell, January 18, 2012
Researchers in the U.S. have disproved the weight-loss tip that suggests smaller plates and portion sizes helps control food intake. For the study, normal weight women and overweight women were randomly assigned to eat lunch on two days. Lunch consisted of spaghetti and tomato sauce, using either a small or large plate. Each subject was asked to self-serve the food onto the assigned plate and told to eat until satisfied. During the second lunch, each subject went through the same procedure but using the alternative size plate. The researchers found that plate size did not have an impact on energy intake because participants, whether normal weight or overweight, ate until they were full regardless of what utensils they used.
"A pilot study to investigate the effect of plate size on meal energy intake in normal weight and overweight/obese women", Journal of Human Nutrition and Dietetics, January 18, 2012
European researchers who examined the regions in the brain involved in appetite sensation found that they are affected by acute sleep loss. Using magnetic imaging (fMRI), the researchers studied the brains of 12 normal-weight males as they looked at images of foods, then compared the results after a night with normal sleep with those obtained after one night without sleep. They found that a single night of total sleep loss curbed energy expenditure the next morning. In addition, subjects had increased levels of hunger, which indicates that an acute lack of sleep may affect human's food perception. The researchers conclude that poor sleep habits can affect people's risk of becoming overweight in the long run.
"Acute Sleep Deprivation Enhances the Brain's Response to Hedonic Food Stimuli: An fMRI Study", The Journal of Clinical Endocrinology & Metabolism, January 18, 2012
Researchers who analyzed data collected between 1998 and 2007 among school children found no correlation between overweight or obesity and the availability of junk food in schools. About 60 percent of fifth graders and 86 percent of eighth graders attended schools that sold junk food such as candy, soda, chips, etc. But despite the big increase in the percentage of students who attended schools that sold junk food between fifth and eighth grades, there was no rise in the percentage of students who were overweight or obese. In fact, the U.S. researchers said, despite the increased availability of junk food, the percentage of students who were overweight or obese actually dropped from fifth grade to eighth grade, from 39.1 percent to 35.4 percent.
"Competitive Food Sales in Schools and Childhood Obesity: A Longitudinal Study", Sociology of Education, January 16, 2012
A protein-based hormone in muscle cells that serves as a chemical messenger could be a very promising candidate for developing novel treatments for diabetes, obesity and perhaps even cancer, U.S. scientists report. The protein apparently triggers some of the key health benefits of exercise. Dubbed “irisin,” it directly affects adipose (fat) tissue that stores excess calories and contributes to obesity. A rise in irisin levels through repeated bouts of prolonged exercise – but not during short-term muscle activity – switches on genes that convert white fat into good “brown” fat, which burns off more calories than exercise itself.
"A PGC1-α-dependent myokine that drives brown-fat-like development of white fat and thermogenesis", Nature, January 11, 2012
Indian scientists who analyzed decades of research on the benefits of dietary fiber (or roughage) report that consuming adequate quantities can improve gastrointestinal health, reduce susceptibility to diseases such as diverticular disease, heart disease, colon cancer, and diabetes. Consuming more dietary fiber has also been associated with increased satiety and weight loss. Dietary fiber – i.e., the non-digestible parts of the fruit and vegetable products we eat – can be obtained from fruit, vegetables, whole-grain foods, such as muesli and porridge, beans and pulses, as readily available foods rich in dietary fiber.
"Dietary fibre and human health", International Journal of Food Safety, Nutrition and Public Health, January 11, 2012
Researchers at the University of Texas have found that significant numbers of young women do not realize that they have gained several pounds over six months. Nearly one-third of women in the study did not recognize weight gain of 4.5 pounds, and nearly one-quarter of women did not recognize gains of 8.8 pounds during a six month interval. Black women and DMPA users (depot medroxyprogesterone acetate, commonly known as the birth control shot) were more likely to recognize weight gain than their counterparts. Failure to recognize recent significant weight gain puts women at risk for cardiovascular disease and other obesity-related conditions. Researchers said self-perception of weight gain appears to be significantly influenced by race, ethnicity and contraceptive methods.
"Self-Perception of Weight Gain Among Multiethnic Reproductive-Age Women", Journal of Women's Health, January 10, 2012
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