Over 42,000 mostly middle-aged men in the Health Professionals Follow-up Study, without diabetes at baseline, were followed over six years to see if diet composition was related to onset of type 2 diabetes. Food intake was determined by a questionnaire. 95% of participants were white.
523 cases of type 2 diabetes developed. Men with the highest glycemic index eating pattern were 37% more likely to develop diabetes compared to the lowest glycemic index.
Cereal (grain) fiber was inversely related to risk of diabetes. That is, the higher the intake of grain fiber, the lower the risk of developing diabetes.
The combination of high glycemic load and low cereal fiber yielded the highest rate of diabetes.
Total dietary fiber was not associated with reduced risk of diabetes.
Fiber from fruits and vegetables was not associated with diabetes one way or the other.
As other studies found, total carbohydrate intake was not related to risk of diabetes.
These findings may or may not apply to women and non-white ethnic groups.
Grains in a minimally refined form reduced the incidence of diabetes in this population.
Diets with a high glycemic load increase the risk of diabetes, at least in men.
Elsewhere, I’ve reviewed studies indicating that, in women, both high glycemic load and high glycemic index eating increase the risk of type 2 diabetes. Click here for details.
We must wonder if established cases of diabetes would respond positively to diets with low glycemic load and grains in a minimally refined form. Or is it too late?
Steve Parker, M.D.
Reference: Salmeron, Jorge, et al. Dietary fiber, glycemic load, and risk of NIDDM in Men. Diabetes Care, 20 (1997): 545-550