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Switching to Whole Grains May Help Improve Insulin/Blood Sugar Management

Insulin is a hormone that helps your body manage your blood sugar, by keeping it from getting too high or too low. In this study, 13 adults with “pre-diabetes” were given a diet with either whole grains or refined grains for 8 weeks, then given a glucose test to assess how well their blood sugar was being managed. They then had a washout period of their normal diet for 8-10 weeks, before switching to the other diet for 8 weeks and taking the glucose test again, thus serving as their own controls. The whole grain diet improved the function of beta cells (the cells that secrete insulin) compared with the refined grain diet, and this effect was found to be independent of gut hormones (such as grehlin, the “hunger hormone”).
Molecular Nutrition and Food Research. 2019 Apr;63(7):e1800967. doi: 10.1002/mnfr.201800967. (Malin SK et al.)

Mediterranean Diet in Adulthood Linked with Healthier Brain in Midlife

While there is much to learn about preventing dementia and cognitive decline, the Mediterranean diet seems to show promise in protecting brain health across the lifespan. In this study, scientists analyzed the eating habits of 2,621 adults at ages 25, 32, and 45 years, then analyzed their brain function at ages 50 and 55. Those most closely following a Mediterranean diet had a 46% lower risk of having poor cognitive function. Those whose diets scored highly on the A Priori Diet Quality Score (a measure of how nutritious your diet is) also had a reduced risk of poor cognitive function, while the DASH diet (a healthy diet to prevent high blood pressure) did not show a significant relationship with brain health.
Neurology. 2019 Apr 2;92(14):e1589-e1599. doi: 10.1212/WNL.0000000000007243. (McEvoy CT et al.)

Plant-Based Diet Linked with Higher Antioxidant Levels, Healthier Fat Distribution

Biomarkers in blood, urine, and fat tissue can provide valuable insight into a person’s diet. In this study, researchers took samples of blood, urine, and fat tissue of more than 800 volunteers. They analyzed the participants diets and divided them into 5 categories: vegan, lacto-ovo-vegetarian, pescatarian, semi-vegetarian, and non-vegetarian. Researcher found that vegans had a significantly higher concentration of antioxidants than non-vegetarians. The results were similar, but less significant, for the other vegetarian groups. They also found that vegans and vegetarians had less saturated fat and more omega-3 fats in their blood than non-vegetarians. The healthier fat distribution and higher concentration of antioxidants and other biomarkers in the vegetarian and vegan groups may help explain some of the benefits of plant-based diets.
The Journal of Nutrition. 2019 Apr 1;149(4):667-675. doi: 10.1093/jn/nxy292. (Miles FL, et al.)

Mediterranean Diet Linked with Improvements in Cardiodiabesity

“Cardiodiabesity” is an umbrella term which refers to the relationship between obesity, cardiovascular disease, metabolic syndrome, and type 2 diabetes. Researchers analyzed over 50 studies to answer several key questions about the impact of the Mediterranean diet on cardiodiabesity. The researchers found strong evidence that following the Mediterranean diet reduces obesity, blood pressure, and the risk of cardiovascular disease in healthy and at-risk people. They also found moderate evidence that the Mediterranean diet reduces the risk of developing metabolic syndrome and type 2 diabetes, and can reduce the symptoms of type 2 diabetes in diabetics.
Nutrients. 2019 Mar 18;11(3). pii: E655. doi: 10.3390/nu11030655. (Franquesa M. et al)

Different Saturated Fats May Have Different Impacts on Health

Replacing saturated fats, like those in butter, cheese, and red meat, with unsaturated fats, like those in walnuts, olive oil, and avocados, can help reduce risk of heart disease. But are all saturated fats created equal? To better assess this relationship, scientists analyzed the diets of 2 large groups of European adults (from Denmark & the U.K.) totaling more than 75,000 participants, and then monitored their health outcomes more than a decade later. In one of the groups (the Denmark group), saturated fats from meat were linked with a higher risk of a heart attack, but other sources of saturated fat were not significantly linked with heart attack risk in either direction. Scientists also noted that lauric acid and myristic acid (saturated fats found in foods like coconut oil) were also linked with lower heart attack risk in the Denmark group, but not the U.K. group. More research is needed to better understand how different foods might relate to heart attack risk.
International Journal of Cardiology.  2019 Mar 15;279:18-26. doi: 10.1016/j.ijcard.2018.10.064. (Praagman J et al.)

Mediterranean Diet Has Long History of Health Benefits

Mediterranean diet first rose to prominence in the 1950’s and since that time has become one of the most-studied diets in the world. In this study, researchers summarize the Mediterranean diet’s scientific history and key takeaways, including its benefits for weight loss and the prevention of heart disease and type II diabetes. The Mediterranean diet has also been linked with the possible prevention of certain types of cancer and neurodegenerative diseases such as Alzheimer’s. The authors note that the erosion of tradition threatens the Mediterranean diet in its place of birth, and that more populations could benefit from adopting a more Mediterranean inspired diet.
International Journal of Environmental Research and Public Health. 2019 Mar 15;16(6). pii:E942. doi: 10.3390/ijerph16060942. (Lăcătușu C-M et al.)

Mediterranean Diet Linked with Lower Rates of Obesity; More Research Needed on Korean Diets and Obesity

The Mediterranean diet is a well-studied cultural model of healthy eating, but less is known about other dietary patterns around the world. In this article, researchers analyzed the relationship between obesity and traditional Mediterranean and Korean diets. The researchers found considerable evidence on the Mediterranean diet’s protective effect against obesity. However, there was no significant association between a traditional Korean diet (a higher carb, lower fat diet with rice, vegetables, fish, and moderate amounts of meat, as well as fermented foods) and obesity. The researchers note that more research is needed on traditional Korean diets and their impacts on health, and that the research could be improved with a standard way of measuring and defining Korean diets. The researchers also noted that many of the Korean diets included in this analysis had higher levels of sodium, and lower levels of fruit and dairy, suggesting that healthier alternatives to some Korean dietary patterns may have a more beneficial impact on health.
Journal of Obesity and Metabolic Syndrome. 2019 Mar;28(1):30-39. doi: 10.7570/jomes.2019.28.1.30. (Choi E et al.)

Small Amounts of Red and Processed Meat Linked with Cardiovascular Death

Seventh-Day Adventism is a religion which promotes a vegetarian diet and overall healthy lifestyle as a spiritual practice. In this study, researchers followed a cohort of over 90,000 Seventh-Day Adventists for an average of about 12 years and analyzed their consumption of red and processed meats. They found that participants who ate the most red and processed meat tended to be less physically active, were more likely to smoke tobacco and drink alcohol, and had a lower intake of fruits, vegetables, legumes, and whole grains than the participants who ate no meat at all. Compared to vegetarians, participants who ate red and processed meat were more likely to die of any cause and of cardiovascular disease. Notably, the participants who ate the most red and processed meat in this study (about 1.5 ounces per day) still have a relatively low consumption when compared to the average American diet (sometimes closer to 5 ounces per day). This suggests that even a low consumption of red and processed meats may have negative health effects.
Nutrients.  2019 Mar 14;11(3). pii: E622. doi: 10.3390/nu11030622. (Alshahrani SM et al)

Mediterranean Diet May Help Prevent Heart Disease

Cochrane reviews are some of the most rigorous reviews in scientific research. In this Cochrane review, researchers analyzed 30 existing randomized controlled trials (the “gold standard” of nutrition research) and 7 ongoing trials of the Mediterranean diet and its impact on heart disease risk. The study found small to moderate evidence for benefits of the Mediterranean diet for preventing heart disease, but note that more research is needed to better understand the benefits, particularly in patients who already have heart disease.
The Cochrane Database of Systematic Reviews. 2019 Mar 13;3:CD009825. doi: 10.1002/14651858.CD009825.pub3. (Rees K et al.)

Frequent Olive Oil Consumption May Be Linked with Making Blood Less Likely to Clot

Olive oil is a well-known heart healthy food, and new research sheds light on a potential explanation behind this benefit. In this study, researchers analyzed the eating habits of 63 obese but otherwise healthy adults, and also analyzed the platelet activity in their blood. (Platelets are the building blocks of blood clots when they stick together.) Those eating olive oil at least once per week had significantly lower platelet activation, indicating that their blood may be less likely to clot. (Note that findings presented at meetings are considered preliminary until published in a peer-reviewed journal.)
Presentation at American Heart Association’s Epidemiology and Prevention | Lifestyle and Cardiometabolic Health Scientific Sessions. Houston, TX. March 7, 2019 (Heffron SP et al.)

Mediterranean Diet in Young Adulthood Linked with Healthier Brain in Middle Age

Eat a nutritious diet while you’re young, and your brain may thank you later. Scientists analyzed the diets of 2,621 young adults (average age: 25) and then assessed their brain health 25 & 30 years later (average ages: 50 & 55, respectively). Those most closely following a Mediterranean diet in young adulthood had a significantly lower decline in cognitive function than those not following a Mediterranean diet.
Neurology. 2019 Mar 6. pii: 10.1212/WNL.0000000000007243. doi: 10.1212/WNL.0000000000007243. [Epub ahead of print] (McEvoy CT et al.)

Mediterranean Diet Linked with Better Bone Mass in Women

A traditional Mediterranean diet includes frequent, but low-to-moderate amounts of dairy products, mostly in the form of artisanal cheeses and yogurts. In this study, researchers analyzed the eating habits and bone density in 442 pre-menopausal women in Spain. Following a Mediterranean diet was linked with significantly better bone mass.
Nutrients. 2019 Mar 5;11(3). pii: E555. doi: 10.3390/nu11030555. (Pérez-Rey J et al.)

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