Dietary glycemic index, glycemic load, cereal fiber, and plasma adiponectin concentration in diabetic men

Adiponectin may improve insulin sensitivity, reduce inflammation, and ameliorate glycemic control. However, few studies have evaluated dietary predictors of plasma adiponectin levels, especially among subjects with type 2 diabetes.

To examine the associations of dietary glycemic load, glycemic index, and fibers with plasma adiponectin levels, we conducted a cross-sectional analysis in 780 diabetic men from the Health Professionals' Follow-up Study. Dietary information was obtained in 1986, 1990, and 1994 using semiquantitative food-frequency questionnaires.

After adjustment for age, BMI, smoking, alcohol consumption, physical activity, aspirin use, HbA(1c), history of hypertension or hypercholesterolemia, and fiber intake, dietary glycemic index and glycemic load were inversely associated with plasma adiponectin in a dose-dependent fashion (P for trend = 0.005 for glycemic index and 0.004 for glycemic load). Adiponectin levels were 13% lower in the highest quintile of dietary glycemic index than in the lowest quintile. For dietary glycemic load, adiponectin levels were 18% lower in the highest quintile than in the lowest. In contrast, high intake of cereal fiber was associated with increased plasma adiponectin levels, adjusting for lifestyle factors and dietary glycemic load (P for trend = 0.003). Adiponectin levels were 19% higher in the highest quintile than in the lowest quintile. Higher magnesium intake was also associated with increased plasma adiponectin.

Diets low in glycemic load and high in fiber may increase plasma adiponectin concentrations in diabetic patients.