Although increasing cereal fiber in the diet appears to reduce the risk of developing type 2 diabetes and coronary heart disease, increased consumption of cereal fiber doesn’t seem to offer beneficial value to people with existing type 2 diabetes.
Researchers in Canada studied the effects of wheat fiber, in the form of wheat bran, on 23 people with type 2 diabetes who underwent two three-month phases of a randomized crossover trial.
Consuming 19 grams per day of additional cereal fiber failed to improve conventional markers of blood-glucose control or risk factors of coronary heart disease when compared to the control period, when subjects consumed only 4 grams per day of additional cereal fiber. The only statistically significant finding was that subjects experienced a slight increase in LDL (“bad” cholesterol) oxidation.
Researchers do not know whether the study period might not have been long enough, whether cereal fiber is a marker for another component of whole grains, or whether people who eat more whole grains practice an overall healthier lifestyle.
A related editorial suggests that more research is needed on the role of various grains.
In the meantime, the editorial says, the recommendation is to continue eating whole-grain foods.
—Diabetes Care, September 2002