Whole grains

Microbes are important for our digestive health, and researchers still have much to learn about how different foods impact our gut microbiome. In this study, researchers cooked 3 days worth of food from 3 different diets (a typical American diet with lots of convenience foods; a USDA recommended healthy diet with whole grains, fruits, vegetables, dairy, and lean meats; and a vegan diet consisting only of plant foods) and then analyzed the microbes present in the foods. The USDA recommended healthy diet was shown to have the highest total microorganisms. However, it was also the only meal plan that included yogurt, a non-heat-treated fermented food well known for its probiotic content.
PeerJ. 2014 Dec 9;(2):e659. doi:10.7717/peerj.659 (Lang JM et al.)

Low bone mineral density causes bones to become weaker, increasing the chance of fractures and osteoporosis. To determine the relationship between diet and bone health, researchers analyzed the food intakes and bone mineral density of over 1800 Korean adults. Four different dietary patterns emerged from this data (rice and kimchi; eggs, meat, and flour; fruit, milk, and whole grains; and fast food and soda). The ‘fruit, milk and whole grains’ pattern was associated with higher bone mineral density at multiple sites for both men and women, while ‘rice and kimchi’ pattern was only associated with higher bone mineral density in the arms. The other food patterns were not linked with bone health.
European Journal of Clinical Nutrition. 2014 Nov 5. [Epub ahead of print] (Shin S et al.)

Whole grains are starting to gain recognition as being rich sources of antioxidants, but many wonder if these antioxidants are affected during processing, such as bread baking. To test this theory, scientists at the University of Maryland measured phenolic acid (antioxidant) content in flour, dough, and bread fractions from three whole and refined wheat varieties. As expected, “all phenolic acids measured were more abundant in whole wheat than refined samples.” The researchers also found no significant change in antioxidant levels after the breads were baked. “Thus, the potential phytochemical health benefits of total phenolic acids appear to be preserved during bread baking.”
Journal of Agricultural and Food Chemistry. 2014 Oct 20 [Epub ahead of print] (Lu Y et al.)

Low diversity of gut microbes is associated with obesity and disease, so it’s important for any healthy diet to increase the variety of these friendly bacteria. In a study in Europe, 20 healthy adults were placed on a 3-week diet rich in whole grains (about 40g fiber, mostly from bread and muesli, and less than 2oz red meat) and a 3-week diet rich in red meat (at least 7oz red meat, and minimal fiber), with a 3-week washout in between. After the red meat diet, diversity of gut microbes remained stable, but after the whole grain diet, the diversity significantly increased. Additionally, although the diets were designed to be isocaloric (meaning that both diets had the same amount of calories), the whole grain intervention produced statistically significant decreases in BMI, weight, and body fat mass, leading researchers to hypothesize that “WG products influence energy utilization.”
PLoS One. 2014 Oct 9;9(10):e109606. (Foerster J et al.)

New research suggests that patients taking statins (cholesterol lowering medication) should also consider eating more whole grains for best results. Boston researchers used dietary recall data and cholesterol levels from 4,284 adults age 45 and older from a national nutrition and health survey. While all statin users had lower non-HDL (a combination of LDL and VLDL or “bad cholesterol”) than non-statin users, high whole grain consumption helped even more. Statin patients also eating more than 16 grams of daily whole grains had non-HDL cholesterol levels that were 11 mg/dL lower than those taking statins but not eating as much whole grain. Whole grain intake and statin use were also significantly linked with healthier  total cholesterol/HDL-cholesterol ratios and total cholesterol concentrations.
American Journal of Clinical Nutrition. 2014 Oct;100(4):1149-57. (Wang H et al.)

Research analyzing the cost of healthy eating suggests that money spent on whole grains is money well spent. In a recent study, scientists collected 3-day food records from 252 youth with type 1 diabetes, then graded them for diet quality and nutrient density. The researchers then calculated the food costs for each participant, to examine the relationship between diet quality and diet cost. The scientists found that higher quality diets came in at a comparable cost to lower quality diets (only $0.68 more per day), as those with the healthiest diets allocated more of their money to whole grains, produce, lean meat, and low-fat dairy, while spending less money on high-fat meat and high-fat dairy.  Based on their results, the researchers concluded, “that cost need not be an insurmountable barrier to more healthful eating,” and that “it is possible to improve diet quality without undue financial burden.”
Journal of the Academy of Nutrition and Dietetics. 2014 September 26. Pii: S2212-2672(14)01218-0. [Epub ahead of print] (Nansel T et al.)

A study commissioned by the Australian Breakfast Cereal Manufacturers Forum analyzed 232 articles to investigate the health benefits and risks of eating cereal. The researchers found that while breakfast cereal consumption of any type is associated with diets higher in vitamins and minerals and lower in fat and a lower body mass index and less risk of being overweight or obese, whole grain breakfast cereal consumption provided even more benefits. Specifically, the study found that oat and barley based cereals can help lower cholesterol, and whole-grain or high-fiber breakfast cereals are associated with a lower risk of diabetes and higher intakes of protein, fiber, niacin, folate, calcium, and zinc. Additionally, the study found that those who eat breakfast cereal regularly have higher whole-grain consumption per day.
Advances in Nutrition. 2014 Sep 15;5(5):636S-73S, (Williams PG et al.)

Dietary fiber is a healthy nutrient found in plant foods, such as fruits, vegetables, whole grains, nuts, and beans. But is the source of fiber important? New research says yes. Korean scientists analyzed studies following over 900,000 people to determine the relationship between fiber intake and mortality. Not surprisingly, those with the highest fiber intake (about 27g/day) had a 23% lower risk of death than those with the lowest fiber intake (about 15g/day). However, upon closer inspection, the researchers found that these results were largely dependent on the foods eaten. As fiber from grains increased, mortality significantly decreased. A similar, although much weaker, relationship was observed for fiber from beans and vegetables, while no association was observed for fruit fiber.
American Journal of Epidemiology. 2014 Sep 15;180(6):565-73. (Kim Y et al).

The new school lunch regulations represent large changes to the food environment of children, so it’s important to study how kids respond to food that’s provided to them. In an effort to see how changing the food environment affects the eating habits of kids, researchers assigned 83 middle schoolers to either a whole grain or refined grain group for six weeks. Participants and their families were given weekly grains (like pasta or cereal) based on their assigned group, and participants also got grain snacks at school. By providing children and their families with whole grain foods,researchers observed that the whole grain group was able to increase their whole grain intake from 1 to 4 servings per day. These results suggest that changing the food environment of children is a successful way to get them to eat more healthy foods, like whole grains.
Journal of the Academy of Nutrition and Dietetics. 2014 Sep;114(9):1417-23. (Radford A et al.)

Restaurateurs hesitant to offer healthier alternatives might want to think again. Nutrition researchers at the University of Minnesota conducted taste tests and studied plate waste data with 120 kids in school cafeterias and 394 kids in restaurants. Not only did they find that children consumed as much of the whole-grain pizza as the refined-grain pizza, but they also discovered that liking ratings for the pizza did not differ by crust type. Based on their research, the authors concluded that “the impact on whole-grain intake could be substantial if large, national restaurant chains served pizza made with whole-grain crust.”
Public Health Nutrition. 2014 Aug 16:1-5 [Epub ahead of print] (Tritt A et al.)