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Red Wine Linked with Diversity of “Friendly Bacteria” in Gut

Moderate red wine intake has been linked with numerous health benefits, and researchers wonder if the gut microbiome might play a role in its protective effect. To test this relationship, researchers analyzed the alcohol intake (red wine, white wine, beer/cider, and spirits) across a group of 916 UK twins, as well as large cohorts of Flemish and American participants. Red wine consumption was linked with significantly greater diversity of gut microbes across all large cohorts studied, and even rare consumption of red wine showed a positive relationship. The authors also found that twins drinking red wine at least 2 categories above their co-twins had significantly higher gut microbe diversity. However, this significant relationship was not observed for the other alcoholic drinks studied.
Gastroenterology. 2019 Aug 23. pii: S0016-5085(19)41244-4. doi: 10.1053/j.gastro.2019.08.024. (CI Le Roy et al.)

Mediterranean Diet Linked with Improvements in Brain Function in Adults Age 70+

What nourishes your body can also help nourish your brain as well. In this study, researchers analyzed the eating habits and brain function of more than 1,400 older adults. In the adults aged at least 70 years old, closely following a Mediterranean diet was linked with improvements in global cognitive function, visual-spatial organization, memory, scanning, and tracking. However, the results were not statistically significant in the adults younger than age 70, or in the group as a whole.
Nutritional Neuroscience. 2019 Aug 21. doi: 10.1080/1028415X.2019.1655201. (Wade AT et al.)

Foods High in Salt, Low in Potassium May Be Linked with Depression in Teens

Highly processed and salty foods tend to be higher in sodium, whereas fruits and vegetables (such as bananas, avocados, dried fruit, lentils, potatoes, and acorn squash) are good sources of potassium. To see how eating habits might relate to depression, researchers took urine samples from 84 urban teens, and screened them for depression at baseline and then again 1.5 years later. Those who had more sodium and less potassium in their urine (a sign of eating high sodium, low potassium foods) were significantly more likely to develop depression at the end of the study period, with a particularly strong association in females. In fact, higher sodium and lower potassium was a better predictor of future depression than baseline depression levels.
Physiological Reports. 2019 Aug;7(16):e14213. doi: 10.14814/phy2.14213. (Mrug S et al.)     

Mediterranean Diet with Olive Oil May Delay Need for Meds in People with Type 2 Diabetes

People with diabetes often need to control their blood sugar using injectable or oral medications, such as insulin. In this study, researchers followed 3,230 people with type 2 diabetes who had been randomly assigned to either a Mediterranean diet with olive oil, a Mediterranean diet with nuts, or a low-fat control diet, and analyzed how the patients managed their blood sugar. Those in the Mediterranean diet with olive oil plan were significantly less likely to need new blood-sugar lowering medications at the 3-year and 5-year follow-up than the low-fat control group. The benefit of the Mediterranean diet with nuts group was not strong enough to be statistically significant. However, it should be noted that 22% of calories in the Mediterranean diet plus olive oil group came from olive oil, while only 8% of the calories in the Mediterranean diet plus nuts group came from nuts.
Diabetes Care. 2019 Aug;42(8):1390-1397. doi: 10.2337/dc18-2475. (Basterra-Gortari FJ et al.)

Native-Born Americans Who Live Near Immigrants Have Healthier Habits

Immigrants who retain their cultural food traditions tend to be healthier than native-born Americans. However, new research indicates that native-born Americans who live in immigrant neighborhoods also tend to have healthier habits than those who don’t live near immigrants. In this study, researchers analyzed the eating habits, blood pressure, and BMI of native-born Americans throughout Los Angeles to see if living in primarily immigrant or primarily native-born neighborhoods has any relationship with health. They found that native-born Americans who live in areas with a high proportion of immigrants tend to eat less fast food and more fruits and vegetables and are less likely to have high blood pressure.
Preventive Medicine. 2019 Aug 6;127:105792. doi: 10.1016/j.ypmed.2019.105792. [Epub ahead of print] (Shi L et al.)

Mediterranean Diet During Pregnancy Linked with Lower Risk of Diabetes During Pregnancy

Gestational diabetes is a form of diabetes that develops in pregnant women, and if left untreated, it can pose risks for birth complications down the road. In this study, researchers randomly assigned participants to either follow a Mediterranean diet (starting at 18-weeks pregnant) or receive their routine care. Those following a Mediterranean diet were 35% less likely to develop gestational diabetes. However, there was no significant relationship detected between the Mediterranean diet and other maternal or child outcomes (such as maternal high blood pressure, still birth, small birth size, or NICU admissions).
PLOS Medicine. 2019 Jul 23;16(7):e1002857. doi: 10.1371/journal.pmed.1002857. (Al Wattar BH et al.)

Plant-Based Diets Linked with 23-30% Lower Risk of Type 2 Diabetes

Plant-based diets, which emphasize healthy plant foods like whole grains, legumes, vegetables, nuts, and fruits, and de-emphasize or eliminate animal foods like meat, dairy, and eggs, are gaining popularity among people with all sorts of dietary preferences. In this study, researchers analyzed the results of 9 observational studies totaling 307,099 participants to see how plant-based diets (including both vegan and vegetarian diets) relate to type 2 diabetes risk. Those most closely following plant-based diets had a 23% lower risk of developing type 2 diabetes across the study periods. When healthy plant-based foods, such as whole grains and vegetables, were included in the definition of plant-based, the relationship was even stronger, at a 30% lower risk.
JAMA Internal Medicine. 2019 Jul 22. doi: 10.1001/jamainternmed.2019.2195. [Epub ahead of print] (Qian F et al.)

Avoiding Wheat Linked with Low Fiber, High Saturated Fat Intakes

Although wheat has been a staple crop for centuries, in recent years it has (unjustly) become a scapegoat by fad-dieters seeking a wheat-free or low-carb diet. In this study, researchers analyzed the diets of 30 people who reported avoiding wheat to see if this wheat-free diet impacted their nutrient intake. The wheat avoiders (many of whom happened to be avoiding dairy as well) consumed too little fiber and calcium, and too much saturated fat and total fat according to dietary recommendations. Interestingly, although 85% of the participants reported avoiding ALL wheat products, ⅓ of the participants reported eating a wheat-based food in their food record (mostly in the form of discretionary snacks/desserts).
Nutrition & Dietetics: The Journal of the Dietitians Association of Australia. 2019 Jul;76(3):305-312. doi: 10.1111/1747-0080.12521. (Golly S et al.)

Low-Carb Paleo Diet Linked with Unhealthy Changes to Gut Microbiome

Paleo diets tend to be high in meat and vegetables, while restricting all grains and dairy products. In this study, researchers analyzed the microbiome of 44 people who had been following a Paleo diet for at least 1 year, and 47 people who eat a healthy diet reflective of dietary guidelines. Those strictly following a Paleo Diet and those eating a standard healthy diet ate significantly more fiber than those only loosely following a Paleo diet. However, those who strictly followed the Paleo diet (eating the lowest levels of whole grains and total grains) were significantly more likely to have higher levels of TMAO (a compound generated by the gut microbiome that is associated with plaque buildup in the arteries). The authors also added that “the rationale to exclude whole grains is not supported by data presented here; being inversely associated with body weight and TMAO concentrations.”
European Journal of Nutrition. 2019 Jul 5. doi: 10.1007/s00394-019-02036-y. [Epub ahead of print] (Genoni A et al.)

Whole Grains, Moderate Alcohol Intake Linked with Lower Diabetes Risk

Numerous studies have been published on diet and diabetes risk, but the quality of these studies varies widely, making it hard to compare the risks and benefits of different food choices. In this analysis, researchers reviewed 53 studies on diet and type 2 diabetes risk, and evaluated their strength and validity. There was high evidence that 30g per day of whole grains was linked with a 13% lower risk of developing type 2 diabetes and that 10g per day of fiber from grains was linked with a 25% lower risk of developing type 2 diabetes. There was also moderate evidence that 0.5-1 ounce of alcohol per day was linked with a 25% lower risk of type 2 diabetes than not drinking at all. On the other hand, eating 3.5 ounces of red meat daily, 2 ounces of processed meat daily, 2 slices of bacon daily, or one serving of sugar sweetened beverages were all strongly linked with a higher risk of type 2 diabetes.
BMJ. 2019 Jul 3;366:l2368. doi: 10.1136/bmj.l2368. (Neuenschwander M et al.)

Gluten-Free Diet Not Appropriate without Medical Diagnosis

Gluten is a compound found naturally in wheat, barley, and rye that helps dough stretch and bread rise. Many misguided dieters today choose to go gluten-free, even though only about 1% of the population has celiac disease (an autoimmune disorder where gluten must be avoided). In this review, researchers analyzed studies on the nutritional adequacy of gluten-free diets. They found that gluten-free diets tend to have less fiber, calcium, magnesium, zinc, vitamin B12, folate, and vitamin D, and tend to have more saturated fat and exposure to arsenic. The researchers note that “the majority of persons adopting a [gluten-free diet] have no medical basis for doing so,” and that “only persons with [celiac disease], [wheat allergy], or [non celiac gluten-sensitivity] should follow a [gluten-free diet], and they should do so under medical supervision.”
Journal of Nutrition and Metabolism. 2019 Jul 1;2019:2438934. doi: 10.1155/2019/2438934. [Diez-Sampedro A et al.]

An Overview of Healthy Phenolic Compounds in Foods

Polyphenols are a type of antioxidant that can combat cell damage, and they are also linked with lower inflammation and lower risks of chronic disease. In this review, researchers analyzed the different types of phenols in foods and how they are commonly measured, noting that “phenols are mainly found in vegetable foods in which the Mediterranean Diet is rich.”
Journal of AOAC International. 2019 Jun 14. doi: 10.5740/jaoacint.19-0128. [Epub ahead of print] (Delgado AM et al.)

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