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Mediterranean Diet Is Linked with Specific Patterns in Gut Microbiota

Although the science is still young, researchers are finding that the foods we eat may influence the bacteria that inhabit our gut. To see how the Mediterranean Diet relates to the gut microbiome, researchers analyzed the diet and gut microbiome of 120 Greek adults. Participants most closely following the Mediterranean diet had lower E.coli levels and a higher bifidobacteria: E. coli ratio, among other favorable microbiome characteristics.
British Journal of Nutrition. 2017 June 5;117(12):1645-1655. (Mitsou EK et al.) 

Fiber Linked with Less Knee Pain Worsening and Less Symptomatic Osteoarthritis

Osteoarthritis is a painful joint condition in which the flexible tissues at the ends of bones get worn down. To see how eating patterns might relate to joint pain in this condition, scientists analyzed the diets of 5,227 US adults (average age = 61) with (or at risk of) osteoarthritis. Those eating 20.6 grams of fiber per day were 30% less likely to develop symptomatic osteoarthritis than those eating only 8.6 grams of fiber per day, and scientists noted a dose-response relationship (meaning that higher fiber intakes are correlated with a lower risk of symptomatic osteoarthritis). Similarly, the researchers found that those eating the most cereal fiber (the type of fiber in whole grains) had a 14% lower risk of knee pain worsening than those eating the least (8.4 grams vs 2.8 grams). However, results were not statistically significant for other types of fiber (such as fiber from fruit or nuts).
Annals of the Rheumatic Diseases. 2017 May 23. [Epub before print.] (Dai Z et al.) 

Plant-Based Diet Can Reduce Obesity Risk by 43%

Nearly every healthy diet around the world is centered on a foundation of colorful produce. To see how eating more plant foods relates to obesity risk, scientists analyzed the diets of 16,000 healthy (non-obese) adults in Spain. Those eating the most plant-based diets (high in fruits, vegetables, grains, nuts, olive oil, and pulses, and low in meat, dairy, seafood, and other animal products) had a 43% lower risk  of becoming obese throughout the 10-year study than those with the most animal-based diets, even after controlling for age, physical activity, and other demographic factors. (Note that findings presented at meetings are typically viewed as preliminary until they’ve been published in a peer-reviewed journal.)
Presented at the European Congress on Obesity. Porto, Portugal. May 18, 2017. (Sanz J et al.)

Pasta Meals Linked with Better Blood Sugar Response

Many are surprised to learn that pasta has a low glycemic index, meaning that it doesn’t spike your blood sugar as much as some other carbohydrate foods, like bread or potatoes. To see how pasta meals relate to health in a broader context, researchers analyzed 18 studies comparing the effects of pasta meals to other types of meals. They found that pasta meals are linked with a lower post-meal blood sugar response than bread- or potato-based meals. However, more research is needed to study how different types of meals relate to cardio-metabolic disease.
Nutrition, Metabolism, and Cardiovascular Diseases. 2017 Jul 18. pii: S0939-4753(17)30160-6. (Huang M et al.)

Mediterranean Diet Associated with Reduced Risk of Frailty

The Mediterranean diet is well known for its ties to healthy aging, but researchers wonder how the Mediterranean diet relates to frailty. In this study, frailty was defined as having at least three of these characteristics: unintentional weight loss, exhaustion, slowness, weakness, and low physical activity. Of the 560 participants, the researchers found that closely following a Mediterranean diet was linked with a 68% lower risk of incident frailty over time and 62% decreased risk of frailty two years later, compared with those not closely following a Mediterranean diet. Following a Mediterranean diet was also linked with a significantly lower risk of poor muscle strength, slowness, and low physical activity.
Clinical Nutrition. 2017 May. [Epub ahead of print.] (Rahi B et al.)

Vegetables at Dinner Linked with Better Academic Performance in Kids

Providing healthy food to children doesn’t just impact their health; it might give them a leg up in the classroom as well. Researchers analyzed the eating patterns and test scores of 4,245 Australian children (ages 8-15) to see if food choices relate to academics. They found that kids who ate vegetables every night at dinner scored significantly higher in spelling and writing than kids who ate the fewest vegetables, and that eating breakfast daily and at least 2 servings of fruit daily were also linked with significantly higher scores in writing. On the other hand, kids who drank the most sugary drinks (like soda) scored significantly lower in reading, writing, grammar/punctuation, and numeracy than those who drank the fewest.
Appetite. 2017 May 6. pii: S0195-6663(17)30374-4. (Burrows T et al.)

Gluten Not Related to Heart Disease, but Avoiding Whole Grains Is

Unless you have celiac disease, you might want to rethink that gluten-free diet. In a study of more than 100,000 US adults without celiac disease, followed for more than 25 years, researchers found that eating gluten was not related to heart disease risk. In fact, the researchers caution that avoiding gluten may result in eating fewer whole grain foods, which may in turn pose a risk for heart disease.
BMJ. 2017 May 2;357:j1892. (Lebwohl B et al.)

Very Low Carb Diet May Impair Athletic Performance

Very low carbohydrate “keto” diets can increase oxygen uptake (VO2 peak). However, this doesn’t necessarily translate to an improvement in athletic performance, and may be detrimental. In this study of 21 race walkers, researchers assigned them to a very low carb “keto” diet, or 2 different types of high carb diets. In the keto diet, the participants experienced reduced economy, meaning their bodies required more oxygen at a given speed, despite their increased VO2 peak. This translated to no improvement in the keto diet group speed, with 5.3-6.6% improvements in speed for the high carb diet groups.
The Journal of Physiology. 2017 May 1;595(9):2785-2807. doi:10.1113/JP273230. (Burke LM et al.)

Whole Grains Linked with Lower Circulating Insulin in Kids

Whole grains have long been associated with chronic disease prevention in adults, but research suggests that children may benefit as well. In this study, researchers analyzed the 7-day food records of more than 700 Danish children and confirmed whole grain intake by also taking biomarkers of whole wheat and rye intake. They found that whole grains and fiber were linked with lower levels of serum insulin, indicating healthier blood sugar management. Additionally, oats were linked with less body fat, and lower systolic blood pressure (the first number in your blood pressure reading), insulin, and LDL (bad cholesterol).
Journal of Nutrition. 2017 May 1;147(5):816-824. (Damsgaard CT et al.)

Mediterranean-Based Diets Associated with Better Cognitive Function

Dementia is a serious neurological disease, so preventive measures are an important area of research.  In a study of 5,907 adults, researchers analyzed whether the Mediterranean diet and/or the MIND diet  (a diet similar to the Mediterranean diet, full of “brain-healthy” foods like leafy greens, nuts, berries, beans, whole grains, seafood, poultry, olive oil, and wine) have an effect on cognitive performance. Researchers found that those most closely following the Mediterranean Diet had 35% lower odds of having poor cognitive performance (assessed through tests of memory and attention), when compared to those not following a Mediterranean Diet. Results were similar for the MIND diet, probably because there is so much overlap in these two eating patterns.
Journal of the American Geriatrics Society. 25 April 2017. [Epub ahead of print.]  (McEvoy CT, et al.)

Mediterranean Diet & Healthy Nordic Diet Linked with Better Survival in Colorectal Cancer

Although food traditions vary from country to country, many traditional healthy diets are rooted in wholesome plant foods like fruits, vegetables, and whole grains. In a study of 1404 people who had been diagnosed with colorectal cancer at least six years prior, researchers analyzed their eating patterns based on how closely they aligned with a Mediterranean diet (fruits, vegetables, grains, unsaturated fats, legumes, moderate alcohol) and a healthy Nordic diet (fish, root vegetables, whole grain bread and oatmeal, apples, pears, cabbage). Those who most closely followed a Mediterranean diet were significantly less likely to die during the study period than those not following a Mediterranean diet. Similarly, each 1-point increase on the Modified Mediterranean Diet Score or the Healthy Nordic Food Index was linked with improved survival.
Journal of Nutrition. 2017 Apr;147(4):636-644. (Ratjen I et al.)

Mediterranean Diet Linked with Smaller Waists, Lower Inflammation, Lower Risk of Insulin Resistance in a Non-Mediterranean Population

Even if you don’t live in the Mediterranean, you can still follow a Mediterranean diet pattern emphasizing healthy foods like fish, whole grains, legumes, and olive oil. In a study of 1,194 Puerto Rican adults in the U.S., researchers analyzed their diets using several different health scores and also collected health measurements from the participants to look for relationships between diet and cardiometabolic health. Those whose diets most closely aligned with a Mediterranean diet were significantly more likely to have smaller waist sizes, a lower BMI, lower levels of inflammation (as measured by C-reactive protein), and lower levels of insulin resistance. The DASH Diet score and Healthy Eating Index 2005 score were not significantly associated with any health measurement, while the Alternative Healthy Eating Index was only weakly associated with some positive health markers.
The Journal of Nutrition. 2017 Apr;147(4):661-669. doi: 10.3945/jn.116.245431. Epub 2017 Mar 8. (Mattei J et al.)

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