With Type 2 Diabetes, Do Whole Grains Make a Difference?

Does processing whole grains impact blood sugar control in those with type II diabetes? We now have a better understanding of this combination thanks to a recent study that compared the impact of milling whole grains on blood sugar control in adults with type 2 diabetes. Subjects in the randomized crossover trial were picked to participate in two interventions lasting 2 weeks, separated by washout. Participants were told to consume intervention foods instead of their usual grain foods. Intervention foods were matched in nutrients to whole grain products including wheat, oats, and brown rice that had different degrees of processing. Those in the study were not advised to change anything else in their lifestyles. Researchers measured blood glucose through continuous glucose monitor systems worn. Pre and post intervention cardiometabolic risk factors were also checked (think alkylreorciols, a biomarker of whole grain consumption).The study included 31 adults with type 2 diabetes with an average age of 63 +/- 13 years old and an average BMI of 32.4 +/- 7 kg/m2 with a Hga1c of 7.5 +/_ 3.4. This group did both interventions. A change in alkylresorcinols was not observed between interventions and no difference in reported calorie consumption was noted. Consumption of less-processed grains resulted in 9% lower postprandial blood sugar after breakfast and 6% lower after other meals when compared to finely milled grains eaten. Day-long glycemic variability was also lower with less processed grains as was body weight. Body weight differed by .81 kg between interventions. It was generally higher with finely-milled grains and lower with less-processed whole grains. While the study was short, the researchers concluded that eating less-processed whole grain foods over 2 weeks showed improved blood sugar in free-living adults with type 2 diabetes when compared to the same amounts of finely-milled whole grains. Dietitians should promote intake of less processed grains. Consider the tips below:

• Choose old-fashioned rolled oats over instant. These cook in 2 minutes in the microwave.
• Switch from white rice to brown rice. Studies show this helps when it comes to reduction in blood sugar in various populations.
• Try bran flakes over corn flakes and wheat Chex in place of corn or rice Chex.
• Use 100% whole grain bread in place of refined white bread.
• Swap 100% whole wheat pasta or bean-based pasta over enriched white pasta.
• Choose whole wheat tortillas in place of white tortillas
• Use whole grain crackers like Triscuits or Wheat Thins in place of Saltines or buttery types of crackers.
• Enjoy air-popped popcorn in place of chips or pretzels.

By Lisa Andrews, MEd, RD, LDReferences:

1. Åberg S, Mann J, Neumann S, Ross AB, Reynolds AN. Whole-Grain Processing and Glycemic Control in Type 2 Diabetes: A Randomized Crossover Trial. Diabetes Care. 2020 Aug;43(8):1717-1723.
2. Malik VS, Sudha V, Wedick NM, RamyaBai M, Vijayalakshmi P, Lakshmipriya N, Gayathri R, Kokila A, Jones C, Hong B, Li R, Krishnaswamy K, Anjana RM, Spiegelman D, Willett WC, Hu FB, Mohan V. Substituting brown rice for white rice on diabetes risk factors in India: a randomised controlled trial. Br J Nutr. 2019 Jun;121(12):1389-1397.