Whole grains

For decades, experts have debated the merits of a low-fat versus a low-carb diet. In this review, nutrition scientists of widely varying perspectives detailed evidence supporting both low-fat and low-carb diets, as well as points of consensus they could agree on. The experts agreed that carbohydrate quality (whole grains and low Glycemic Index foods over refined grains and sugars) and fat quality (unsaturated fats over trans fats and saturated fats) are much more important than the amount of carbohydrates or fat in the diet.
Science. 2018 Nov 16;362(6416):764-770. doi: 10.1126/science.aau2096. (Ludwig DS et al.)

Metabolic syndrome is a cluster of conditions (high blood pressure, high blood sugar, high cholesterol, and excess fat around the waist) that can increase your risk of heart disease, stroke, and diabetes if they occur together. In this study, researchers randomly assigned more than 100 adults with metabolic syndrome from Finland and Italy to a diet with whole grains or a control diet without whole grains for 12 weeks. The whole grain group had better blood sugar control after meals. Researchers hypothesize that this may be because eating whole grains may help stimulate the production of certain chemical compounds (betaine compounds, such as pipecolic acid betaine) which are linked with improved insulin resistance and insulin secretion.
American Journal of Clinical Nutrition. Am J Clin Nutr. 2018 Sep 25. doi: 10.1093/ajcn/nqy169. [Epub ahead of print]. (Kärkkäinen O et al.)

To better understand whole grains’ relationship with heart health, New Zealand’s Heart Foundation analyzed 19 meta analyses encompassing thousands of participants, for their September 2018 report entitled “Whole Grains and the Heart.” The authors conclude that “observational research suggests three [servings] of whole grains per day are associated with heart health benefits, and there are likely to be additional benefits with higher intakes. Intervention studies on risk factors are less compelling but show most consistent evidence of benefits for a small reduction in total and LDL cholesterol, especially in relation to oats and barley, and possibly improved [glycemic] control.”
Heart Foundation. 2018 Sept. (Gorton D et al.)

Whole grains are healthy carbohydrate foods that may be especially protective against type 2 diabetes. In this study, researchers analyzed the eating habits and health status of 55,465 middle-aged adults in Denmark. Those eating more whole grains were 11% and 7% less likely to develop type 2 diabetes (for men and women, respectively) over the 15-year study period. Rye bread, whole-grain bread, oatmeal, and muesli were all significantly associated with a lower risk of type 2 diabetes for both men and women, indicating a benefit for whole grains in general, rather than just one specific type of whole grain food.
The Journal of Nutrition. 2018 Sep 1;148(9):1434-1444. doi: 10.1093/jn/nxy112. (Kyrø C et al.)

Many parents buy gluten-free foods for their kids because they think that those foods are healthier. But unless you have a medically-diagnosed reason to avoid gluten (such as celiac disease), evidence suggests otherwise. Researchers in Canada went to 2 major supermarket chains and purchased all foods marketed to kids (with the exception of candy, soda, and a few other “junk foods”) – 374 products total. They then analyzed the nutrition labels of the foods, to see how products marketed as gluten free stacked up to those not marketed as gluten free. For a more direct comparison, they then identified 43 gluten-free foods marketed to kids that had a non-gluten-free counterpart, and compared nutrition between the matched products. Overall, nutrition was poor among all kids’ products, gluten-free or not, and there were few significant differences. Specifically, products marketed as gluten-free had slightly lower levels of sodium, but slightly higher levels of added sugar. Additionally, a higher proportion of gluten-free products had high levels of trans fat. The researchers concluded that “[gluten-free] supermarket foods that are targeted at children are not nutritionally superior to regular child targeted foods and may be of greater potential concern because of their sugar content,” adding that “parents who substitute [gluten-free] products for their product equivalents (assuming [gluten-free] products to be healthier) are mistaken.”
Pediatrics. 2018 Aug;142(2). pii: e20180525. (Elliott C et al.)

Sugar build up between your teeth can cause cavities and other dental problems, but certain food choices can have a protective effect. To see how different carbohydrates play a role, researchers analyzed 28 studies comparing rapidly digestible starches (refined grains) to slowly digestible starches (whole grains). Some evidence suggests that whole grains lower the risk of oral cancer and gum infection (periodontitis), and that refined grains may significantly increase cavities, but more research is needed. The researchers conclude that “the best available evidence suggests that only [rapidly digestible starches] adversely affects oral health.”
Journal of Dental Research.  2018 Aug 3. [Epub ahead of print.] (Halvorsrud K et al.)

Though many Paleo dieters believe that bread is a relatively “new” foodstuff, archeological evidence paints a different picture of what ancient diets were like for our hunting and gathering ancestors. Archeologists analyzed the remains of ancient fireplaces in what is today Jordan, and found the oldest empirical evidence of bread-like products from 14,400 years ago. These ancient flatbreads existed 4,000 years before Neolithic agriculture, and challenge previous assumptions about grains’ role (or lack thereof) in ancient, Epipaleolithic diets.
Proceedings of the National Academy of Sciences. 2018 Jul 31;115(31):7925-7930. (Arranz-Otaegui A et al.)

Around the globe, increasing whole grain intake is widely recognized as an important dietary goal to improve public health. In this study, researchers analyzed 8 whole grain interventions in Australia, the US, the UK, the Netherlands, and Denmark, to determine the best practices for promoting whole grains. The authors conclude that “successful interventions included multiple stakeholder involvement, specified target intakes in dietary guidelines, and codes of practice for labeling WG foods.”
Journal of Nutrition Education and Behavior. 2018 Jul 31. pii: S1499-4046(18)30554-2. (Suthers R et al.)

Not all carbohydrates are created equal. After all, everything from quinoa and blueberries to candy bars and soda have carbohydrates. In this review, researchers examined the links between different types of carbohydrates and health. They concluded that whole grains are linked with numerous health benefits, including lower cholesterol, body fat, and healthier blood sugar management, as well as lower risks of type 2 diabetes, heart disease, many cancers, and death from all causes. Given that much of the research on whole grains is done using more processed whole grain products (like breakfast cereals and breads), the authors note that more research is needed to determine if intact whole grains without as much added sugar may have even greater health benefits.
BMJ. 2018 June 13. (Ludwig DS et al.) [Epub ahead of print.]

Brains tend to shrink in people who are suffering from dementia and other cognitive diseases, so researchers wonder if lifestyle factors may relate to brain structure. Scientists analyzed the eating habits and brain volume (using MRIs) of more than 4,000 adults without dementia. Eating lots of vegetables, fruits, whole grains, nuts, dairy, and fish, and drinking fewer sugary drinks was linked with larger brain volumes. Healthier diets were also linked with more gray matter, white matter, and hippocampal volume in the brain.
Neurology. 2018 May 16. (Croll PH) [Epub ahead of print.]