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American Diet Slowly Gets a Tiny Bit Better, Still Needs Improvement

The standard American diet is infamous for its high levels of refined carbs, sugar, and saturated fats. To see if nutrition initiatives are taking hold, researchers analyzed the diets of 43,996 U.S. adults in 1999 and then again in 2016. Over this time period, people got 1.23% more calories from high quality carbs (whole grains), 0.38% more calories from plant protein, 0.65% more calories from polyunsaturated fats, and 3.25% fewer calories from low quality carbohydrates (sugar and refined grains). Unfortunately, calories from saturated fat increased by 0.36%, and the general diet is still far from ideal, with 42% of calories still coming from low quality carbs, and saturated fat remaining above 10% of energy intake.
JAMA. 2019 Sep 24;322(12):1178-1187. doi: 10.1001/jama.2019.13771.(Shan Z et al.)

Racial & Ethnic Minorities Carry Disproportionate Burden of Diabetes at Lower BMI

Being heavier for our stature (as measured by BMI) puts us at a higher risk of diabetes. In this study, researchers analyzed the prevalence of diabetes in nearly 5 million people. Hispanics, Asians, and Hawaiians/Pacific Islanders who were overweight had the same diabetes risk as whites, blacks, and Native Americans who were in the most obese tier (class 4 obesity). Further, they found that the link between BMI and diabetes is strongest in whites and lowest in blacks, indicating that other factors outside of overweight/obesity may increase diabetes risk in racial and ethnic minorities.
Diabetes Care.  2019 Sep 19. pii: dc190532. doi: 10.2337/dc19-0532. [Epub ahead of print] (Zhu Y et al.)

Sourdough Fermentation Methods Improve Quality of Partially Whole Wheat Pasta

Swapping out some of the white flour for whole wheat flour in pasta is a simple way for manufacturers to bump up the nutritional quality of their products. But researchers wonder if different whole wheat pasta formulations might be better than others. In this study, researchers compared the nutritional and sensory (taste, acceptability, etc.) characteristics on two types of partially (28.5%) whole wheat fresh pasta: in one, the whole wheat flour was fermented (essentially a sourdough starter) and in the other, the whole wheat flour was not fermented. The fermented pasta showed a higher content of free essential amino acids and phenolic compounds, lower phytic acid content, and higher antioxidant activity. In consumer testing in a group of 54 people, the fermented pasta was rated higher for overall acceptability (taste, texture, and flavor). Interestingly, when people were told about the use of sourdough fermentation in the pasta, the acceptability ratings were even higher, reflective of the growing appetite for functional foods.
Foods. 2019 Sep 18;8(9). pii: E422. doi: 10.3390/foods8090422. (Fois S et al.)

Whole-Food Plant-Based Diet Linked with Weight Loss, Healthier Gut Microbiome

Researchers randomly assigned 148 overweight and obese adults to a low-fat vegan diet, or to continue their usual diet for 16 weeks. Those in the vegan group lost about a pound per week, and also lost a significant amount of body fat. Additionally, the vegan group (who ate lots of legumes, fruits, vegetables, and nuts) also had higher levels of beneficial bacteriodetes in their gut. This may partially explain some of the health benefits of plant-based diets, because people with diabetes, insulin resistance, and inflammation tend to have low levels of bacteriodetes. (Note that findings presented at meetings are considered preliminary until published in a peer-reviewed journal.)
Presentation at European Association for the Study of Diabetes 2019 Annual Meeting. Barcelona, Spain. September 17, 2019.

Going Gluten-Free Does Not Improve Digestive Symptoms in Healthy Volunteers

If you don’t have a medically-diagnosed problem with gluten, is there any benefit to going gluten-free? New research suggests not. In this study, scientists randomly assigned 28 people without medical problems with gluten to a gluten-free diet or a gluten-containing diet for 2 weeks. The gluten-containing diet did not generate any symptoms (diarrhea, reflux, constipation, fatigue, etc.) in these healthy volunteers. They concluded that because a gluten-free diet is often less healthy than a typical diet, “there is possibly clinical justification in actively discouraging people from starting it if they have no diagnosable sensitivity.”
Gastroenterology. 2019 September;157:881-883. doi: 10.1053/j.gastro.2019.05.015. (Croall ID et al.)

AMERICANS CAN CORRECTLY CATEGORIZE MOST FOODS AS WHOLE GRAIN OR REFINED GRAIN

In this study, researchers asked 169 low-income adults to look at 11 foods in their original packaging and determine if each was a whole grain or a refined grain. The majority of participants (7 out of 10) correctly identified 4 out of 5 of the whole grain products as whole grain, and nearly as many (6 out of 10) participants correctly identified 5 out of the 6 refined grain products. Specifically, 9/10 people correctly identified whole grain bread, 8/10 correctly identified whole grain crackers & whole grain cereal, and 7/10 correctly identified oatmeal as a whole grain, while popcorn tripped most people up (with only 3/10 people correctly identifying it as a whole grain food). Similarly, 8/10 correctly identified refined crackers, 7/10 correctly identified refined macaroni and tortillas, and 6/10 correctly identified refined bread and cereal, while white rice was tricky for people (with only 4/10 correctly identifying it as a refined grain). Based on interviews with a subset of 60 of the participants, the researchers found that helping people more clearly identify whole grains on the package, and reducing the cost (or perceived cost) of whole grain foods may help increase whole grain consumption in low-income adults.
Current Developments in Nutrition. 2019 May 16;3(7):nzz064. doi: 10.1093/cdn/nzz064. (Chea M et al.)

Whole Wheat Promotes Resilience in Liver, Protects Against Higher Inflammation

Health not only implies being free of disease; health also takes into account how well we adapt to the stresses of everyday life, and the inevitable wear-and-tear on our bodies – in other words, resilience. To see how whole wheat might impact inflammation and resilience, 50 overweight and obese adults were randomly assigned to either 98 grams of whole wheat per day (from bread and cereal) or 98 grams of refined wheat per day for 12 weeks. Scientists then measured markers of inflammation and liver health and used modeling (the “health space” approach) to determine how resilient their bodies were to external stressors based on these findings. In this experiment, whole wheat was shown to protect against higher inflammation, and was also shown to promote resilience in the liver. 
Journal of Nutrition. 2019 Aug 27. pii: nxz177. doi: 10.1093/jn/nxz177. (Hoevenaars FPM et al.)

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.)

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