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Red Meat Linked with Risk Factor for Heart Disease

TMAO is a potentially dangerous metabolite linked with heart attacks and stroke, so researchers wonder how diet can impact the amount of TMAO that our bodies produce. In this study, researchers assigned 113 adults to a high-saturated fat or low-saturated fat diet for 4 weeks, with a washout period before switching to the other diet. Interestingly, saturated fat did not impact TMAO. However, eating lots of red meat (but not white meat or nonmeat) was linked with significantly higher levels of TMAO through 3 different mechanisms (nutrient density of TMA precursors, increased production from carnitine, and reduced TMAO excretion).
European Heart Journal. 2018 Dec 10. doi: 10.1093/eurheartj/ehy799. (Wang Z et al.)

Mediterranean Diet Linked with ¼ Lower Heart Disease Risk in Women

The Mediterranean diet is closely linked with heart health, and researchers want to learn more about the underlying mechanisms behind this connection. In this study researchers analyzed the diet and health outcomes of 25,994 women for 12 years. Those most closely following a Mediterranean diet were 28% less likely to develop heart disease than those not following a Mediterranean diet. Even those who were only moderately following a Mediterranean diet had a 23% lower risk of heart disease, indicating that even small lifestyle changes can have a meaningful impact on health. The researchers suspect that part of the heart health benefits may be related to lower inflammation, as women most closely following the Mediterranean diet had significantly lower levels of biomarkers of inflammation. Other factors shown to affect the relationship between the Mediterranean diet and heart health are the Mediterranean diet’s links to blood sugar management, BMI, blood pressure, and cholesterol.
JAMA Network Open. 2018 Dec 7;1(8):e185708. doi:10.1001/jamanetworkopen.2018.5708 (Ahmad S et al.)

Mediterranean Diet with Dairy May Help with Blood Pressure and Cholesterol

In a traditional Mediterranean diet, dairy was eaten often, but in small amounts (typically fermented dairy products, like artisanal cheese and Greek yogurt). Researchers wonder if a Mediterranean diet with slightly more dairy might still offer some benefits, so they randomly assigned 41 adults at risk of heart disease to a Mediterranean diet with 3-4 servings of dairy per day, or a low fat diet. Compared to a low fat diet, the Mediterranean dairy diet resulted in significantly higher HDL (good) cholesterol, lower triglycerides (a fat in the blood) and significantly lower blood pressure in the morning. However, more research is needed to see how a traditional Mediterranean diet compares with a higher dairy Mediterranean diet.
American Journal of Clinical Nutrition. 2018 Dec 1;108(6):1166-1182. doi: 10.1093/ajcn/nqy207. (Wade AT et al.)

Switch to Whole Wheat for Better Liver Health

The liver is important for metabolism, so researchers wonder how substituting whole grains might impact liver health. To assess this relationship, 50 overweight middle-aged adults were randomly assigned to a diet with 5 servings of whole wheat foods per day or 5 servings of refined wheat foods per day for 12 weeks, and compliance was confirmed by measuring biomarkers of whole wheat intake (alkylresorcinol). The refined wheat diet significantly increased liver fat, indicating that it may contribute to the development of nonalcoholic fatty liver disease. On the other hand, the whole wheat diet prevented an increase in liver fat, and better maintained liver health.
American Journal of Clinical Nutrition. 2018 Dec 1;108(6):1264-1274. doi: 10.1093/ajcn/nqy204. (Schutte S et al.)

Frequent Family Dinners Linked with Healthier Eating, Even in "Dysfunctional" Families

Sharing meals amongst friends and family is an important component of traditional diets and lifestyles around the world. Families who eat together tend to eat healthier, but researchers wonder whether this holds true in more dysfunctional families. To assess this relationship, researchers analyzed the eating habits of 2,728 adolescents living at home, and also surveyed them on how well their family functions together. More frequent family dinners were linked with healthier diets, including more fruits and vegetables, and less take-out and fast food, regardless of how well the family functions together.
JAMA Network Open2018 Nov 21;1(7):e185217. doi:10.1001/jamanetworkopen.2018.5217 (Walton K et al.)

Fruits and Vegetables Linked with Healthy Brain Function Later in Life

Fruits and vegetables are the cornerstone of healthy traditional diets around the globe. In this study, researchers analyzed the fruit and vegetable intake of 27,842 men and monitored their brain health 20 years later. Not surprisingly, those eating more vegetables, fruit, and fruit juice were significantly less likely to have poor late-life subjective cognitive function, indicating healthier brain function.
Neurology. 2018 Nov 21. pii: 10.1212/WNL.0000000000006684. doi: 10.1212/WNL.0000000000006684. (Yuan C et al.)

Mediterranean Diet Filled with Health-Promoting Polyphenols

Polyphenols are naturally occurring antioxidants found in many foods including olive oil, fruits, vegetables, nuts, legumes, whole grains, and red wine; these foods are also key components of the traditional Mediterranean diet. In this review researchers analyzed the main sources of polyphenols in the Mediterranean diet and their potential health impacts. They found that the Mediterranean diet has a unique mix of polyphenols that is associated with decreased obesity; the polyphenols present in the Mediterranean diet may also promote the growth of good bacteria in the gut, which may aid in digestion and have other positive health effects.
Nutrients. 2018 Oct 17;10(10). pii: E1523. doi: 10.3390/nu10101523. (Castro-Barquero S et al)

Quality Trumps Quantity When Choosing Carbs and Fats

For decades, experts have debated the merits of a low-fat versus a low-carb diet. In this review, nutrition scientists of widely varying perspectives detailed evidence supporting both low-fat and low-carb diets, as well as points of consensus they could agree on. The experts agreed that carbohydrate quality (whole grains and low Glycemic Index foods over refined grains and sugars) and fat quality (unsaturated fats over trans fats and saturated fats) are much more important than the amount of carbohydrates or fat in the diet.
Science. 2018 Nov 16;362(6416):764-770. doi: 10.1126/science.aau2096. (Ludwig DS et al.)

Eating Omega-3 Fatty Acids While Pregnant May Reduce Pre-Term Births

Not many women eat fish frequently during pregnancy, but perhaps they should. In a rigorous Cochrane review of 70 randomized controlled trials (involving 19,927 women), scientists found that getting more omega-3 fatty acids (from food, like seafood, or supplements) may reduce the incidence of pre-term birth and low birthweight in babies.
The Cochrane Database of Systematic Reviews. 2018 Nov 15;11:CD003402. doi: 10.1002/14651858.CD003402.pub3. (Middleton P et al.)

Plant-Based Korean Diet with Brown Rice Can Improve Blood Pressure and Blood Sugar in Hospitalized Patients

Many people are surprised at how effective lifestyle changes can be when it comes to managing chronic disease. In this study, 160 hospital patients in South Korea with high blood pressure changed their diet to eat a plant-based (vegan) diet based on brown rice at each meal, with lots of kimchi and pickled vegetables, fermented soy foods, and lots of other vegetables (both raw and cooked). They averaged about 1,700 calories per day and did not eat any refined grains or any noodles or breads, relying on brown rice as the staple. Their sodium intake was quite high, at 7,382mg per day. However, after about 2 weeks, 86% of the patients were able to stop taking their blood pressure and diabetes medications, and their reduced blood pressure levels remained stable even after stopping the medications. Similarly, HBA1C reduced from 7.6 to 7.2, indicating better blood sugar management. More research is needed to see if similar approaches might be effective in other populations.
Journal of Ethnic Foods. 2018 Nov 1. DOI: https://doi.org/10.1016/j.jef.2018.09.002 (Jung SJ et al.)

Mediterranean Diet Linked with Better Brain Health in Adults at Risk for Alzheimer's

Numerous studies have observed a link between the Mediterranean Diet and slower cognitive decline, but researchers wonder how this might relate to the development of Alzheimer’s disease. To better understand diet’s relationship with Alzheimer’s pathology, scientists analyzed the eating patterns and buildup of Aβ (small pieces of protein that can accumulate in the brain, potentially creating plaques and causing brain cells to be destroyed) in 77 older adults who were already on the path to Alzheimer’s disease (by being flagged as being Aβ accumulators). Those most closing following a Mediterranean diet had significantly less Aβ accumulation over time, with fruit standing out as a particularly beneficial food. The authors suggest that improving your Mediterranean diet score by just 1 point (0-9 point scale) may result in a 20% decrease in Aβ accumulation over 1 year, and up to a 60% decrease over 3 years.
Translational Psychiatry. 2018 Oct 30;8(1):238. doi: 10.1038/s41398-018-0293-5. (Rainey-Smith SR et al.)

Waist Circumference Guidelines May Differ for African Americans

Waist circumference is an easy-to-measure predictor of diabetes and heart disease risk, but one measurement may not indicate the same level of risk across all races or body types. In this study, researchers analyzed the waist circumference, body fat, and insulin resistance of 375 African-born black adults living in America. They found that a waist circumference of 38 inches or greater in black women, and 36 inches or greater in black men is predictive of insulin resistance, which indicates increased diabetes risk. This differs from the existing waist circumference thresholds for white adults. The researchers suggest that public health organizations review the research on waist circumference and adopt African-centered thresholds for African Americans, rather than a one-size-fits-all approach.
BMJ Global Health. 2018 Oct 15;3(5):e001057. doi: 10.1136/bmjgh-2018-001057. (Kabakambira JD et al.)

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