Whole grains

Don’t let a poor diet keep you up at night. In this study, researchers analyzed the diets and insomnia rates of more than 50,000 post-menopausal women. Eating more whole grains, fiber, fruit, and vegetables was linked with lower odds of insomnia. On the other hand, eating more added sugar, starch, refined grains, and a high glycemic index diet (diet of foods that raise your blood sugar quickly) was linked with higher odds of insomnia.
American Journal of Clinical Nutrition. 2020 Feb 1;111(2):429-439. doi: 10.1093/ajcn/nqz275. (Gangwisch JE et al.)

Healthy menu items are seemingly easier to find at restaurants than they were ten years ago, but are people actually eating these dishes? To find out, researchers analyzed the nutritional content of fast-food and full-service restaurant dishes eaten by 35,015 adults between 2003 and 2016. Although the overall diet quality remained poor for both fast-food and full-service restaurant meals eaten by the participants, there are a few promising signs of progress. Notably, whole grains eaten at restaurants increased from 0.22 to 0.49 servings per day in full-service restaurants, and 0.08 to 0.31 servings in fast food restaurants. There were also slight increases in nut/seed/legume intake at fast food restaurants, as well as slight decreases in soda consumption at full-service restaurants and saturated fat and sodium consumption at fast food restaurants. Unfortunately, over this time period, people also at fewer fruits and vegetables at both types of restaurants, and the nutritional disparities between different racial and ethnic demographic groups persisted and, in some cases, worsened.
Journal of Nutrition. 2020 Jan 29. pii: nxz299. doi: 10.1093/jn/nxz299. [Epub ahead of print] (Liu J et al.)

Eating a healthy, well-balanced diet is known to help prevent numerous chronic diseases, so it’s no surprise that eating healthier can reduce healthcare costs, too. In this study, researchers analyzed U.S. eating habits against dietary recommendations, and then calculated the cardiometabolic disease burden (heart diseases, stroke, type 2 diabetes) attributable to not meeting specific dietary guidelines. From there, they were able to calculate the costs associated with not meeting specific dietary recommendations. They found that diet-related healthcare costs were $301 per person annually (or $50.4 billion total) for cardiometabolic diseases alone. Specifically, the per-person annual cardiometabolic cost of not eating enough nuts & seeds was $81, seafood omega-3 fats was $76, vegetables and legumes was $60, fruits was $57, and whole grains was $45.
PLoS Medicine. 2019 Dec 17;16(12):e1002981. doi: 10.1371/journal.pmed.1002981. eCollection 2019 Dec. (Jardim TV et al.)

A balanced diet can go a long way towards nourishing our bodies, our brains, and our feelings. In this study, 76 young adults (ages 17-35) with symptoms of depression were randomly assigned to either continue their typical diet or eat a healthier diet with whole grains, fruits, vegetables, nuts, lean protein, and fish for 3 weeks. After the study period, those eating the healthier diet had significantly lower self-reported depression symptoms than the control group, and some of the beneficial results were maintained 3 months after the study as well.
PLoS One. 2019 Oct 9;14(10):e0222768. doi: 10.1371/journal.pone.0222768. (Francis HM et al.)

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.)

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.

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.)

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.)

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.)

Hepatocellular carcinoma is the most common form of liver cancer. In this study of 125,455 adults in the U.S., eating more whole grains was linked with a significantly lower risk of developing hepatocellular carcinoma over the 24-year study period. The results were statistically significant for whole grains overall and were not statistically significant when looking at bran intake, germ intake, or fiber from whole grains, thus indicating that the whole grain is greater than the sum of its parts.
JAMA Oncology. 2019 Jun 1;5(6):879-886. doi: 10.1001/jamaoncol.2018.7159. (Yang Y et al.)