Different Oat Products Elicit Different Glycemic Responses

The Glycemic Index is a measure of how much a food spikes your blood sugar (0-55 is low, 56-69 is medium and 70-100 is high). To see if different oat products have different effects on blood sugar, researchers from Quaker Oats tested the Glycemic Index of 72 oat products. They found that steel cut oatmeal, large flake oatmeal, muesli, and granola produced a significantly lower Glycemic Response (53-56, in the low/medium range) than quick cooking and instant oatmeal (71-75, in the medium/high range). The scientists concluded that “smaller particle size and increased starch gelatinisation appear to increase the glycemic response.”
British Journal of Nutrition. 2015 Oct 28;114(8):1256-62. (Tosh SM et al.)

Replacing Butter, Sugar, or Refined Grains with Whole Grains Cuts Heart Disease Risk

Harvard researchers followed over 120,000 adults for 24-30 years, tracking their diet and health records. The scientists found that replacing 5% of daily calories from saturated fat (like butter, cream, and red meat) with whole grains is associated with a 9% lower risk of heart disease, but replacing saturated fat with refined grains or added sugars does not lower heart disease risk. Additionally, they found that replacing 5% of daily calories from refined grains and added sugars with whole grains or polyunsaturated fats (found in fish, nuts, seeds, and safflower oil) can also significantly reduce heart disease risk. The researchers concluded, “Our findings provide epidemiological evidence of the current dietary guidelines, which recommend both “replacing saturated fatty acids with monounsaturated and polyunsaturated fatty acids” and “replacing refined grains with whole grains.””
Journal of the American College of Cardiology. 2015 Oct;66(14):1538-48. (Li Y et al.)

Whole Grains, Especially Oats, May Lower Cholesterol

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.)

Whole Grain Intake Linked with Lower Stroke Risk

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.)

Carbs (Like Whole Grains) Vital to Early Human Brains

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.)

Whole Grains Offer Benefits Beyond Fiber

Whole grains are well known for their fiber; however, fiber is not the only benefit of a diet rich in whole grains. This study uses nutritional metabolomics (a field of that looks at how different foods affect metabolism) to explore how the different compounds in whole grains may affect metabolism, and suggests scientific reasons behind the health benefits of whole grains, beyond just their fiber content. Specifically, this analysis suggests that whole grains may have positive effects on insulin sensitivity and protein metabolism, and may contain other beneficial compounds, such as glycine betaine.
Proceedings of the Nutrition Society. 2015 Aug;74(3):320-7. doi: 10.1017/S0029665114001542. Epub 2014 Oct 23. (Ross AB et al.)

High Phytate Foods (Beans, Nuts, Whole Grains, etc.) May Help Young Women Better Absorb Iron over Time

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 May Prevent Early Death

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]

Gluten Free Foods Are Not Healthier

While most whole grains are naturally gluten free (like quinoa, millet, and rice), many gluten-free packaged foods are made with refined, starchy flours, such as potato flour or white rice flour. To see how gluten free products stack up, researchers analyzed the nutrition on over 3200 food products in Australia, comparing the health of gluten free items to items containing gluten. Gluten free products were found to have significantly less protein across all major food groups, and gluten free pasta was found to be significantly less healthful than regular pasta (based on the Australian government’s “Health Star Rating”). Other than that, the researchers found no significant health differences between gluten free (GF) and gluten-containing products, concluding that “the consumption of GF products is unlikely to confer health benefits, unless there is clear evidence of gluten intolerance.”
British Journal of Nutrition. 2015 Jun 29:1-7. [Epub ahead of print]. (Wu JH et al.)

Refined Grains Linked with Depression

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 Diet with Whole Grains May Improve Prostate Cancer Survival

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.)

Fiber from Whole Grains May Reduce Diabetes Risk

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).