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Processed Barley & Oats Linked with Less Gut Microbiota Diversity

A healthy diversity of gut microbiota is associated with numerous health benefits. To see how processing grains relates to the microbiome in animals, researchers analyzed the gut microbiota of pigs after feeding them whole grain barley and oats, or extruded whole grain barley and extruded oats. Extrusion is a process used to make pasta, cereal, croutons, and other grain products, by sending a flour and water mixture through a die to get uniform shapes. The gut microbiota of pigs eating the extruded grains showed less diversity and less presence of the microbes associated with health. The researchers concluded that “cereal extrusion affects the microbiota composition and diversity towards a state generally thought to be less beneficial for health.”
Food & Function. 2016 Feb;7(2):1024-32. (Moen B et al.)

Low Level Mercury Exposure from Fish Appears Safe During Pregnancy

Seafood is a staple in many traditional diets, but many wonder if the health benefits of fish consumption outweigh the risk of mercury exposure. In a study of 334 infants in Ohio, researchers assessed the neurobehavior of infants and the fish intake and blood mercury levels in mothers and cord blood. The researchers “found minimal evidence of mercury associated detrimental effects” on the infants, with no statistically significant problems related to level of mercury consumption when other lifestyle and dietary factors were controlled for. In fact, the researchers also observed that the infants with higher (but still safe) blood mercury levels had better attention and less need for special handling, suggesting that the benefits of fish consumption may outweigh the risks of low-level mercury exposure.
Neurotoxicology and Teratology. 2016 Feb 12. Pii: S0892-0362(13)30007-1. (Xu Y et al.)

Seafood Linked with Fewer Signs of Alzheimer’s Disease

To see how fish consumption and mercury exposure relate to Alzheimer’s, scientists analyzed the food intake of over 500 retired adults in Chicago each year for several years. They then autopsied the brains of 286 of the deceased participants to study signs of Alzheimer’s disease and measure levels of mercury in the brain. The scientists found that eating at least one seafood meal per week was linked with less Alzheimer’s disease pathology (including lower density of neuritic plaques, less severe and widespread neurofibrillary tangles, and lower neuropathologically defined Alzheimer’s disease) in participants with genetic predisposition to Alzheimers disease (APoE4 allele carriers). They also found that higher brain concentrations of mercury were not linked with increased signs of Alzheimer’s disease, and that fish oil supplementation had no effect on these markers.
JAMA. 2016 Feb 2;315(5):489-97. (Morris MC et al.)

Eating Fiber in Young Adulthood Linked with Lower Breast Cancer Risk

Dietary fiber is an important nutrient found in plant foods (mostly in whole grains, fruits, vegetables, and pulses). To study the link between fiber intake and breast cancer risk, Harvard scientists analyzed the adolescent and early adulthood diets of over 90,000 women, and noted any diagnosis of breast cancer. The researchers found that every 10g of fiber in adolescence and young adulthood was linked with a 14% and 13% lower risk of breast cancer, respectively. In fact, those eating the most fiber in adolescence and young adulthood (25g per day) were 25% less likely to get breast cancer than those eating the least fiber (12g per day).
Pediatrics. 2016 Feb 1. pii: peds.2015-1226. (Farvid MS et al). 

Consuming Fat from Plant Oils May Help Prevent Cardiac Death

In a large study, researchers from the Global Burden of Diseases Nutrition and Chronic Diseases Expert Group analyzed the fat consumption and coronary heart disease statistics of 186 nations across the world. They found that 10.3% of coronary heart disease deaths were attributable to not eating enough n-6 polyunsaturated fats (found in soy, walnuts, sunflower seeds, and some plant oils), while 7.7% were due to eating too much trans fat (found in margarine and highly processed foods), and 3.6% were due to eating too much saturated fat (found in red meat and butter). In 80% of nations studied, deaths from heart disease due to inadequate n-6 polyunsaturated fats was at least double the heart disease deaths due to too much saturated fat. This suggests that positive messages focused on adding in healthy foods (such as cooking vegetables in plant oils, and sprinkling nuts and seeds on meals) can have an important impact on public health.
Journal of the American Heart Association. 2016 Jan 20;5(1). Pii: e002891. (Wang Q et al.) 

Vegetarian Diets Linked with Weight Loss

To determine if vegetarian diets might be useful for weight loss, Harvard researchers analyzed results from 12 different clinical trials encompassing 1,151 people. Those assigned to vegetarian diets lost 4.5 pounds more compared to those assigned to a non-vegetarian control diet, regardless of whether or not calories were restricted. Participants assigned to vegan diets (excluding all animal products) lost more weight (5.6 pounds) than those assigned to lacto-ovo vegetarian diets (3.2 pounds). The diets ranged from 9 weeks to 74 weeks, with a median duration of 18 weeks. The scientists conclude that “Vegetarian diets appeared to have significant benefits on weight reduction compared to non-vegetarian diets.”
Journal of General Internal Medicine. 2016 Jan;31(1):109-16. (Huang RY et al.)

Green Leafy Vegetables Linked with Lower Risk of Eye Disease

Primary open-angle glaucoma is an eye disease that can lead to irreversible vision loss. Because there is currently no cure for this disease, scientists are very interested in preventive measures, including diet. In a study analyzing over 100,000 health professionals, Harvard researchers found that those eating 1.45 servings of green leafy vegetables per day had an 18% lower risk of developing primary open-angle glaucoma than those only eating 0.31 servings of leafy greens per day. Dietary nitrate (a nutrient found in green leafy vegetables), was also significantly related to a lower risk of primary open-angle glaucoma.
JAMA Opthalmology. 2016 Jan 14:1-11. (Kang JH et al.) [Epub ahead of print]

Gluten Free Med Diet Improves Nutrition in Celiac Patients

Maintaining a healthy weight and optimal nutrition can be a struggle for patients with celiac disease, but nutritious diets can help. In a small Italian study, researchers assigned 39 celiac patients to a Mediterranean gluten-free diet. The scientists found that celiac patients following a gluten free diet based on the Mediterranean diet improved their nutritional status, without inducing overweight or obesity. In fact, two of the four malnourished celiac patients were able to reach a healthy BMI, without becoming overweight or obese.
European Journal of Clinical Nutrition. 2016 Jan;70(1):23-7. (Barone M et al.)

Vegan Diets Linked with Lower Risk of Prostate Cancer

Over a quarter of cancer cases in men are prostate cancer, so dietary strategies to prevent prostate cancer could benefit many. To study this relationship, scientists analyzed the diet and prostate cancer diagnoses in a group of over 26,000 men for nearly 8 years. They found that vegan diets (diets that exclude all animal products, including dairy and eggs) were linked with a 35% lower risk of prostate cancer than non-vegetarian diets that included meat, poultry, fish, dairy, and eggs. Other vegetarian diets (that include dairy and eggs) did not show a statistically significant protective effect.
American Journal of Clinical Nutrition. 2016 Jan;103(1):153-60. (Tantamango-Bartley Y et al.)

Diabetes-Protective Changes to Gut Bacteria after Year on Med Diet

In a small study, Spanish researchers randomly assigned 20 obese men to either a Mediterranean diet, or a low fat, high complex carbohydrate diet (with foods like pasta and cereals) for a year. After a year on their respective diets, both groups saw increases in various gut microbes that are thought to be protective against type 2 diabetes (Roseburia and Parabacteroides  distasonis for Med diet, and Prevotella and Faecalibacterium prausnitzii for low fat, high complex carb diet). The Mediterranean diet group also increased their insulin sensitivity over the year, meaning that their bodies better respond to insulin.
The Journal of Clinical Endocrinology and Metabolism. 2016 Jan;101(1):233-42. (Haro C et al.)

Med Diet Linked with Improved Gut Bacteria

Spanish researchers randomly assigned 239 adults (half with metabolic syndrome, half without) to either a Mediterranean diet, or a low fat, high complex carbohydrate diet (with foods like pasta and cereals) for two years. They found that the Mediterranean diet was able to “restore potentially beneficial members of the gut microbiota,” in patients both with and without metabolic syndrome. The low fat, high complex carbohydrate diet did not result in as many positive changes in gut microbiota as the Mediterranean diet did, although some beneficial changes still occurred.
The Journal of Nutritional Biochemistry. 2016 Jan;27:27-31. (Haro C et al.)

Mediterranean Diet During Pregnancy Linked with Lower Abdominal Obesity in Young Children

To see how diet during pregnancy affects the risk of childhood obesity, researchers analyzed data from over 1,800 mother-child pairs. They found that children were less likely to have a high waist circumference (a measure of abdominal obesity) at age 4 if their mothers were most closely following a Mediterranean diet during pregnancy. However, the researchers found no significant relationship between the expectant mothers’ diet and the subsequent BMI of their children in early childhood.
Pediatric Obesity. 2016 Jan 13. (Fernandez-Barres S) [Epub ahead of print]

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