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Unhealthy "Southern Diet" Partially Explains High Blood Pressure Risk in African Americans

African Americans are disproportionally affected by high blood pressure (a risk factor for heart disease), so health experts wonder what might contribute to this risk. In a study of 6,897 adults, researchers found that eating a “southern diet” (lots of fried food, processed meats, added fats, and sugar sweetened beverages) accounted for 51.6% of the increased risk of high blood pressure in black men, and 29.2% of the increased risk among black women. Celebrating traditional, nutrient-dense African heritage cuisine could be a helpful approach to encourage people of diverse backgrounds to make healthier food choices, thereby reducing risk for high blood pressure.
JAMA. 2018 Oct 2;320(13):1338-1348. doi: 10.1001/jama.2018.13467. (Howard G et al.)

Mediterranean Diet Linked with 33% Lower Risk of Depression

Scientists are eager to learn more about the link between a healthy diet and a healthy mind. In this study, researchers analyzed existing observational studies between healthy diets (measured by the Mediterranean Diet score, the Healthy Eating Index, the Dietary Inflammatory Index, and related scoring systems) and depression. According to the researchers, “the most compelling evidence was found for the Mediterranean diet and incident depression.” Specifically, those most closely following a Mediterranean diet were 33% less likely to develop incident depression than those not following a Mediterranean diet. People whose diets scored well on some of the other diet scores also tended to have a lower risk of depression, though there were fewer studies using those indices.
Molecular Psychiatry. 2018 Sep 26. doi: 10.1038/s41380-018-0237-8. [Epub ahead of print] (Lassale C et al.)

Whole Grains Linked with Better Blood Sugar Management

Metabolic syndrome is a cluster of conditions (high blood pressure, high blood sugar, high cholesterol, and excess fat around the waist) that can increase your risk of heart disease, stroke, and diabetes if they occur together. In this study, researchers randomly assigned more than 100 adults with metabolic syndrome from Finland and Italy to a diet with whole grains or a control diet without whole grains for 12 weeks. The whole grain group had better blood sugar control after meals. Researchers hypothesize that this may be because eating whole grains may help stimulate the production of certain chemical compounds (betaine compounds, such as pipecolic acid betaine) which are linked with improved insulin resistance and insulin secretion.
American Journal of Clinical Nutrition. Am J Clin Nutr. 2018 Sep 25. doi: 10.1093/ajcn/nqy169. [Epub ahead of print]. (Kärkkäinen O et al.)

Mediterranean Diet Linked with 22% Lower Risk of Stroke in Women

The Mediterranean diet has been well studied for its link to stroke prevention, but researchers wonder how the effects may differ between different types of patients. In this study, scientists monitored the eating patterns and health status of 23,232 white Europeans in the UK. After 17 years, those most closely following a Mediterranean diet had a 17% lower risk of stroke. However, the findings seem to be driven primarily by women. Women who most closely followed a Mediterranean diet had a 22% lower risk of stroke, while the trend towards lower risk in men was not statistically significant. Additionally, the findings were stronger in people who had a higher risk of heart disease (due to family history or other factors).
Stroke. 2018 Sept 20. doi: 10.1161/STROKEAHA.117.020258. [Epub ahead of print.] (Paterson KE et al.)

Whole Grains Linked with Lower Cholesterol

To better understand whole grains’ relationship with heart health, New Zealand’s Heart Foundation analyzed 19 meta analyses encompassing thousands of participants, for their September 2018 report entitled “Whole Grains and the Heart.” The authors conclude that “observational research suggests three [servings] of whole grains per day are associated with heart health benefits, and there are likely to be additional benefits with higher intakes. Intervention studies on risk factors are less compelling but show most consistent evidence of benefits for a small reduction in total and LDL cholesterol, especially in relation to oats and barley, and possibly improved [glycemic] control.”
Heart Foundation. 2018 Sept. (Gorton D et al.)

Cheese Production in Mediterranean May Have Helped Reduced Infant Mortality in Middle Neolithic Period

The Neolithic Period, when communities transitioned from a largely hunter-gatherer lifestyle to a largely agricultural lifestyle, began about 12,000 years ago. Cheese production in the Mediterranean was thought to have begun in the Bronze Age (after the Neolithic Period). However, newly discovered fatty acid residue on pottery from Neolithic sites in Croatia indicates that milk was fermented into cheese much earlier than had been assumed, in the Middle Neolithic period (5200 BCE). The researchers suggest that “dairying and fermentation had additional human life-history dependent advantages by reducing infant mortality,” which “helped stimulate demographic shifts that propelled farming communities to expand and provided the demographic and dietary risk buffering to allow Neolithic farming to spread to colder, temperate climates.”
PLoS One. 2018 Sep 5;13(9):e0202807. doi: 10.1371/journal.pone.0202807. (McClure SB et al.)

Shifting to Healthy Vegetarian Diets Could Lower Earth's Water Footprint by 35-55%

Scientists are beginning to discover that eating choices that are best for people also happen to be best for the planet. Researchers from the European Commission’s Directorate for Sustainable Resources analyzed national food surveys, water footprint databases, and other datasets across the UK, France, and Germany to determine how the water footprint changes when people shift their diet. They found that shifting from the current eating pattern to a healthy eating pattern (that contains meat) cut reduce the water footprint by 11-35%, and that even larger reductions could be made by shifting to a healthy pescatarian (vegetarian with fish) diet (33-35% reduction) or a healthy vegetarian diet (35-55% reduction).
Nature Sustainability. 2018 Sept 1. doi: 10.1038/s41893-018-0133-x. (Vanham D et al.)

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.)

Whole Grains Associated with Lower Risk of Diabetes

Whole grains are healthy carbohydrate foods that may be especially protective against type 2 diabetes. In this study, researchers analyzed the eating habits and health status of 55,465 middle-aged adults in Denmark. Those eating more whole grains were 11% and 7% less likely to develop type 2 diabetes (for men and women, respectively) over the 15-year study period. Rye bread, whole-grain bread, oatmeal, and muesli were all significantly associated with a lower risk of type 2 diabetes for both men and women, indicating a benefit for whole grains in general, rather than just one specific type of whole grain food.
The Journal of Nutrition. 2018 Sep 1;148(9):1434-1444. doi: 10.1093/jn/nxy112. (Kyrø C 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 unless you have a medically-diagnosed reason to avoid gluten (such as celiac disease), 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.)

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