Whole grains

In a small European study, researchers supplied 33 adults who rarely eat whole grains (less than one ounce per day) with diet advice and a variety of whole grain foods. The participants increased their whole grain intake by 500% for six weeks (averaging six ounces per day) so that the scientists could assess diet’s relationship with gut bacteria, body fat and blood chemistry (like blood pressure and cholesterol). While the scientists found no significant health changes during this short-term experiment, what was remarkable is how the participants’ attitudes towards whole grains changed throughout the study. According to the researchers, nearly two thirds (65%) of the participants who provided post study data said they now prefer whole grains, “citing benefits such as improved bowel movements and appetite suppression, as well as taste.” Additionally, “the majority of subjects reported that it was not difficult to achieve the required level,” and a whopping 76% of subjects intend to continue eating and purchasing whole grains.
The Journal of Nutrition. 2015 Feb;145(2):215-21 (Ampatzoglou A et al.)

It appears that a ‘grain brain’ may be protective against Alzheimer’s. Researchers studied the relationship between eating patterns and Alzheimer’s in 923 retired adults in Chicago over an average of 4.5 years.  The scientists rated participants’ diets based on how closely they adhered to the Mediterranean diet, the DASH diet (a healthy diet used to treat hypertension that emphasizes fruits, vegetables, whole grains, low fat dairy, and limited sweets and salt) and the MIND diet. The MIND diet is a hybrid Mediterranean-DASH diet that emphasizes foods associated with brain health, including 3 servings per day of whole grains (more than any other food group), along with green leafy vegetables, berries, nuts, olive oil, and fish. The groups most closely following either the MIND diet or the Mediterranean diet cut their risk of Alzheimer’s dementia by more than half (53% for MIND and 54% for Mediterranean), while those closely following the DASH diet were 39% less likely to develop Alzheimer’s. Even those moderately following the MIND diet were at a 35% lower risk.
Alzheimer’s and Dementia. 2015 Feb 11. pii: S1552-5260(15)00017-5. [Epub ahead of print] (Morris MC et al.)

Chronic obstructive pulmonary disease (COPD), a type of lung disease, is commonly associated with smoking, even though up to one third of COPD patients have never smoked. In order to determine how other lifestyle factors may influence the risk of COPD, researchers analyzed over a decade of eating habits and new COPD cases from over 73,000 adult nurses in the US. The scientists concluded that diets high in whole grains, nuts, heart-healthy fats (polyunsaturated and omega-3), and low in red meat and sugar-sweetened drinks were associated with a significantly lower risk of COPD. This study adds to the growing body of evidence that whole grains are a vital component of an overall healthy diet.
British Medical Journal. 2015 Feb 3;350:h286. (Varraso R et al.)

Eating more whole grains may help you live longer! Researchers from the Harvard School of Public Health analyzed data from over 110,000 adults. The scientists found that every one-ounce serving of whole grains was associated with a 5% lower total risk of death, or a 9% lower risk of death from heart disease. Whole grain intake was not significantly associated with cancer mortality. The researchers of this study conclude “these results are in line with recommendations that promote increased whole grain consumption to facilitate disease prevention.”
JAMA Internal Medicine. 2015 Jan 5.  [Epub ahead of print] (Wu H, et al.)

We know that healthy microbes are present in yogurt and other fermented foods, but research is showing that these friendly bacteria are actually present all throughout healthy diets. Researchers at the University of California, Davis measured the microbes in meals from three common diets: the standard American diet (consisting of fast food and convenience foods, and no whole grains), a vegan diet (which included oatmeal and peanut butter, a vegetable and tofu soup with soba noodles, and a Portobello burger on a whole wheat bun), and a healthy diet based on the USDA dietary guidelines (which included whole grain cereal with fruit and yogurt, a turkey sandwich on whole wheat bread, and a quinoa, chicken, and vegetable dinner). Researchers found that the microbe level in both whole grain diets outnumbered that of the standard American diet lacking in whole grains. The USDA diet had 1.3 billion microbes per day, the vegan diet had 6 million microbes per day, and the standard American diet had only 1.4 million microbes per day. While it’s unclear whether the benefit can be traced directly to whole grains or to a combination of interacting factors, this study points to the overall benefits of a healthy diet including whole grains.
PeerJ. 2014 Dec 9. (Lang J M et al.)

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.)