Whole grains

Whole grains are important to our brain health today, but new evidence suggests that they were also vital to our brain development millions of years ago. Researchers in Europe and Australia examined diet’s role in the development of early humans, and found that carbohydrates (such as whole grains, root vegetables, and other starchy plant foods) were “necessary to accommodate the increased metabolic demands of a growing brain.” While most depictions of early human foods emphasize hunter-gatherer diets full of meat, the scientists argue that cooked starches permitted “the acceleration in brain size increase from the Middle Pleistocene onward.”
The Quarterly Review of Biology. 2015 Sept;90(3):251-268. (Hardy K et al.)

It is estimated that up to 80% of strokes can be prevented, so food choices to protect against strokes are an important area of research. Scientists in China analyzed six large prospective studies following over 247,000 people to see how whole grain intake related to stroke risk. Those eating the most whole grains had a 14% lower risk of stroke than those eating the least whole grains. The authors concluded that “higher whole grain intake has a protective effect on stroke.”
International Journal of Clinical and Experimental Medicine. 2015 Sep 15;8(9):16978-83 (Fang L et al.)

Even modest reductions in cholesterol are thought to help prevent heart disease, so heart healthy diets are an important area of research. To determine the link between whole grains and cholesterol, scientists analyzed the results of 24 randomized controlled trials (totaling 2,275 participants). They found that eating whole grains is associated with lower LDL (“bad”) cholesterol and total cholesterol, with no significant effect on HDL (“good”) cholesterol or triglycerides (a type of fat in the blood). Whole grain oats specifically seemed to be linked with the greatest cholesterol lowering effects compared to other whole grain foods. The length of the study was also associated with positive changes in cholesterol, indicating health benefits are greater for those who make whole grains a regular part of their daily lifestyle.
The American Journal of Clinical Nutrition. 2015 Sept;102(3):556-72. (Hollaender PLB et al.)

Phytates are compounds found in many plant foods, especially in beans and whole grains. Although phytates are linked with health benefits, they can also block the absorption of non-heme iron (the type of iron found in beans and other plant sources). To see how eating these phytate-rich foods affects nutrition status, scientists in Iowa assigned 28 non-anemic young women to either a high phytate (lots of whole grains, beans, nuts, and tofu) or low phytate (refined grains, eggs, and cheese, avoiding high phytate foods) diet for eight weeks, then tested their iron levels. After consuming a high phytate diet for 8 weeks, there was a 41% increase in serum iron response (measured by area under the curve). This indicates that “habitual consumption of [a high phytate] diet can reduce the negative effect of phytate on non-heme iron absorption among young women with sub-optimal iron stores.”
Journal of Nutrition. 2015 Aug;145(8):1735-9. (Armah SM et al.)

Whole grains (like rye, oats, and whole wheat) have a strong history in traditional Scandinavian cuisine, but as in other regions, the food landscape is changing and refined grains have replaced some traditional foods. To see how eating whole grains relates to mortality, researchers analyzed the diets of over 120,000 people in Denmark, Norway, and Sweden.  The scientists found that those who ate the most whole grains had significantly lower risk of death from all causes. When analyzing individual whole grains, the researchers found significantly lower mortality rates in those who ate the most whole grain breakfast cereals, whole grain bread, oats, rye (only statistically significant for men), and whole wheat. These findings support existing evidence that whole grains may contribute to longevity.
British Journal of Nutrition. 2015 July 23:1-16. (Johnsen NF et al.) [Epub ahead of print]

It seems that comfort foods like refined sweets might not be so comforting in the long run. Scientists in New York analyzed the eating patterns of nearly 70,000 women without depression across the U.S. , then tracked their health records over three years to see how diet relates to developing depression. The researchers found that both refined grains and added sugars were significantly tied to a higher risk of developing depression over the three year study, while fiber, vegetables, fruit (excluding juice), and lactose (a sugar found in milk) was linked with a significantly lower risk of depression. A higher intake of whole grains was also related to a lower risk of depression, although this relationship was not statistically significant. Overall, foods that contributed to a high glycemic index diet were associated with increased odds of developing depression. 
American Journal of Clinical Nutrition. 2015 Jun 24. [Epub ahead of print] (Gangwisch JE et al.)

Healthy diets are an effective way to help prevent diseases, like cancer, but emerging research shows that they can also improve survival in people who have already been diagnosed. In a study of over 900 male physicians diagnosed with prostate cancer, Harvard researchers analyzed their eating patterns and followed their health records for 14 years after diagnosis. They found that men who ate a typical “Western diet” (high in red and processed meat, high fat dairy foods, and refined grains) had more than twice the risk of prostate-cancer related death, and a 67% increased risk of death from all causes. On the other hand, those who ate a healthy diet (with whole grains, fruits, vegetables, fish, and healthy oils) had a 36% lower risk of death from all causes. This study affirms that nutritious, balanced diets promote the best health outcomes, and that whole grains are an integral component of an overall, healthy diet.
Cancer Prevention Research. 2015 June 1. [Epub ahead of print] (Yang M et al.)

Studies have shown that fiber (especially from whole grains) may lower diabetes risk in Americans, but researchers wanted to know if the same was true in Europe. Analyzing the eating patterns of over 26,000 participants from 8 nations in Western Europe, the scientists found that total fiber was associated with a lower risk of diabetes, along with fiber from whole grains and vegetables (but not fruit). The researchers then combined these results with the results of 18 additional studies, following over 617,000 participants, and found that fiber from whole grains was the most protective. Indeed, for every additional 10g of total fiber or cereal fiber (the fiber in whole grains), the risk of type 2 diabetes was 9% or 25% lower, respectively. However, these results were not significant after adjusting for weight, meaning that whole grains and fiber likely play an important role in weight maintenance, another risk factor for type 2 diabetes.
Diabetologia. 2015 May 29. [Epub ahead of print] (InterAct Consortium).

Minorities and low-income populations are often underrepresented in nutrition studies, but new research indicates that healthy diets with whole grains can benefit all of us, including underserved populations. In this study, researchers examined the diets and medical records of over 77,000 people from 12 states in the southeastern US, most of whom were low-income and African American. Researchers found that those most closely adhering to a healthy diet (including at least 1 ½ servings of whole grains per day) had a 14-23% lower death rate from all diseases, heart disease, cancer, and more. Additionally, while overall dietary patterns are the best way to assess health, whole grains specifically were associated with a lower death risk (as were dairy, seafood, and plant proteins).
PLOS Medicine. 2015 May 26;12(5):e1001830; discussion e1001830. (Yu D et al.)

Eating whole grains daily may help keep breast cancer at bay. Approximately 1 in 8 women are diagnosed with breast cancer, and lifestyle factors are thought to play an important role in prevention. To determine the relationship between eating patterns and breast cancer, researchers analyzed the diets of 250 newly diagnosed female breast cancer patients, and 250 age-matched controls (without cancer). The scientists found that eating whole grains at least 7 times per week was associated with a decreased risk of breast cancer.
Journal of the American College of Nutrition. 2015 Apr 27:1-7 [Epub ahead of print] (Mourouti N et al.)