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Healthy Diets (Like Mediterranean, Vegetarian) May Improve Gut Microbiome

Scientists are increasingly interested in researching the gut microbiome, the community of bacteria of our digestive tract, as studies suggest that the types of microbes we produce and carry around may impact our risk for chronic disease. In this review, researchers analyzed the existing research on diet and the gut microbiome, focusing on vegetarian diets and Mediterranean diets. Both epidemiological studies and randomized clinical trials demonstrate that healthy Mediterranean and vegetarian diets are linked with various beneficial changes to the gut microbiome (such as increased short chain fatty acid production, increases in Prevotella, and decreases in trimethylamine). They suggest that these healthy diets may lower risk of chronic disease by impacting our gut microbiome, but that more research is needed to identify the exact mechanism.
Journal of Nutrition. 2018 Sep 1;148(9):1402-1407. doi: 10.1093/jn/nxy141. (Tindall AM et al.)

Mediterranean Diet Linked with Prolonged Survival in Elderly

The Mediterranean Diet is well known for its links with longevity, but researchers wonder if this protective effect might apply to an elderly population as well. In a study of 5,200 older adults in Italy (ages 65+), researchers found that those most closely following a Mediterranean diet were significantly less likely to die over the 8-year study period. In fact, each 1-point increase in the Mediterranean Diet Score (0-9 point scale) was linked with a 4-7% lower risk of death from all causes over the 8 years.
British Journal of Nutrition. 2018 Aug 30:1-14. doi: 10.1017/S0007114518002179. [Epub ahead of print] (Bonaccio M et al.)

Low Carb Diets Linked with Early Death

There are countless different diets out there, from low carb to high carb to everything in between. But which eating pattern is linked with longer lives? Scientists are on a mission to find out. Researchers analyzed the eating habits and health outcomes of 15,428 adults in the US, following them for 25 years. The “sweet spot” for the lowest risk of mortality was diets that had 50-55% of their calories from carbohydrates, especially those with lots of plant foods, like whole grain bread, nuts, vegetables, and peanut butter. This amount aligns with traditional diets (such as the Mediterranean diet), as well as the US Dietary Guidelines for Americans. On the other hand, low-carb diets that had lots of meat were linked with higher mortality.
The Lancet Public Health. 2018 Aug 16. pii: S2468-2667(18)30135-X. [Epub ahead of print.] (Seidelmann SB et al.)

Gluten Free Kids' Foods No Healthier than Regular Kids' Foods

Many parents buy gluten-free foods for their kids because they think that those foods are healthier. But in reality, evidence suggests otherwise. Researchers in Canada went to 2 major supermarket chains and purchased all foods marketed to kids (with the exception of candy, soda, and a few other “junk foods”) – 374 products total. They then analyzed the nutrition labels of the foods, to see how products marketed as gluten free stacked up to those not marketed as gluten free. For a more direct comparison, they then identified 43 gluten-free foods marketed to kids that had a non-gluten-free counterpart, and compared nutrition between the matched products. Overall, nutrition was poor among all kids’ products, gluten-free or not, and there were few significant differences. Specifically, products marketed as gluten-free had slightly lower levels of sodium, but slightly higher levels of added sugar. Additionally, a higher proportion of gluten-free products had high levels of trans fat. The researchers concluded that “[gluten-free] supermarket foods that are targeted at children are not nutritionally superior to regular child targeted foods and may be of greater potential concern because of their sugar content,” adding that “parents who substitute [gluten-free] products for their product equivalents (assuming [gluten-free] products to be healthier) are mistaken.”
Pediatrics. 2018 Aug;142(2). pii: e20180525. (Elliott C et al.)

For Healthy Teeth, Choose Whole Grains Instead of Refined

Sugar build up between your teeth can cause cavities and other dental problems, but certain food choices can have a protective effect. To see how different carbohydrates play a role, researchers analyzed 28 studies comparing rapidly digestible starches (refined grains) to slowly digestible starches (whole grains). Some evidence suggests that whole grains lower the risk of oral cancer and gum infection (periodontitis), and that refined grains may significantly increase cavities, but more research is needed. The researchers conclude that “the best available evidence suggests that only [rapidly digestible starches] adversely affects oral health.”
Journal of Dental Research.  2018 Aug 3. [Epub ahead of print.] (Halvorsrud K et al.)

Evidence of Ancient Flatbreads Pre-Dates Neolithic Agriculture

Though many Paleo dieters believe that bread is a relatively “new” foodstuff, archeological evidence paints a different picture of what ancient diets were like for our hunting and gathering ancestors. Archeologists analyzed the remains of ancient fireplaces in what is today Jordan, and found the oldest empirical evidence of bread-like products from 14,400 years ago. These ancient flatbreads existed 4,000 years before Neolithic agriculture, and challenge previous assumptions about grains’ role (or lack thereof) in ancient, Epipaleolithic diets.
Proceedings of the National Academy of Sciences. 2018 Jul 31;115(31):7925-7930. (Arranz-Otaegui A et al.)

Successful Whole Grain Public Health Campaigns Require Multiple Stakeholders

Around the globe, increasing whole grain intake is widely recognized as an important dietary goal to improve public health. In this study, researchers analyzed 8 whole grain interventions in Australia, the US, the UK, the Netherlands, and Denmark, to determine the best practices for promoting whole grains. The authors conclude that “successful interventions included multiple stakeholder involvement, specified target intakes in dietary guidelines, and codes of practice for labeling WG foods.”
Journal of Nutrition Education and Behavior. 2018 Jul 31. pii: S1499-4046(18)30554-2. (Suthers R et al.)

Mediterranean Diet Linked with Less Severe Psoriasis

Psoriasis is an inflammatory disease that causes itchy rashes on the skin. Since the Mediterranean diet has been known to lower inflammation, researchers wonder whether it may also help with psoriasis. In an online survey, researchers analyzed the eating habits of 35,735 French adults, and also surveyed them about psoriasis. Those most closely following a Mediterranean diet were 22-29% less likely to report having severe psoriasis than those not following a Mediterranean diet. The researchers concluded that “the Mediterranean diet may slow the progression of psoriasis.”
JAMA Dermatology. 2018 Jul 25. [Epub ahead of print.] (Phan C et al.)

Mediterranean Diet in Teens Linked with Better Sleep, Academic Performance

The Mediterranean diet is full of foods that promote brain health, so it stands to reason that this eating pattern may be especially beneficial for students. To see how the Mediterranean diet relates to sleep and brain health, researchers analyzed the eating patterns, sleep quality, sleep duration, school grades, and exam scores of 269 13-year-olds in Spain. Closely following a Mediterranean diet was linked with better sleep quality, as well as higher GPAs, and better grades in math, language, and core subjects. The researchers suggest that better sleep quality may play a role in the Mediterranean’s relationship with improved academic performance.
Acta Paediatrica. 2018 Jul 17. [Epub ahead of print.] (Adelantado-Renau M et al.)

Med Diet Linked with Less Death, Heart Attacks in People with History of Heart Disease

Even if you already have heart disease, it’s never too late to improve your health. Researchers analyzed the eating habits and health status of 3,562 adults with heart disease, to see how different eating patterns relate to further health complications down the road (like death or heart attacks). Those most closely following a Mediterranean diet were 20% less likely to die from all causes and 22% less likely to have a cardiovascular event (like a heart attack) during the 7-year follow up. On the other hand, a “Southern Diet” (lots of added fats, fried food, eggs, organ meats, processed meats, and sweetened beverages) was linked with a higher risk of death from all causes during the 7-year follow up. 
Journal of the American Heart Association. 2018 Jul 12;7(14). pii: e008078. (Shikany JM et al.)

Mediterranean Diet with Vit D Improves Neck Bone Mineral Density in Adults with Osteoporosis

A traditional Mediterranean diet has frequent but small portions of fermented dairy (like artisan cheeses or Greek yogurt), a food group widely associated with bone health. To see how a Mediterranean diet relates to bone health, researchers randomly assigned 1,142 elderly European adults to a Mediterranean diet with a vitamin D3 supplement, or a control group with pamphlets on healthy eating tips. After 1 year, the Mediterranean diet & vitamin D intervention had no effect on bone mineral density for most participants. However, in the small subset of participants (54 people) who already had osteoporosis, the Mediterranean diet & vitamin D intervention significantly reduced the rate of bone loss at the femoral neck, but had no effect on lumbar spine or whole-body bone-mineral density.
American Journal of Clinical Nutrition. 2018 Jul 11. [Epub ahead of print.] (Jennings A et al.)

Processing Corn to Remove Bran & Germ Reduces Nutrients

While some processing methods can improve the nutrition of food, some can also detract from it. To see how the nutrients in corn are impacted as corn is processed into cornflakes breakfast cereal, researchers analyzed the nutrient content at 5 points throughout the process (whole kernel, flaked grit, cooked grit, baked grit, and toasted cornflake). The scientists found that a large drop-off in phenolic acid (healthy phytochemicals that have antioxidant properties) occurred after the whole kernel was milled into flaked grits, when the bran and germ were removed. Smaller losses occurred at other points in the processing method as well, but were not as staggering.
Journal of Visualized Experiments. 2018 Jun 16;(136). (Butts-Wilmsmeyer C et al.)

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