OBJECTIVE -The purpose of this study was to examine the associations of dietary fibers and glycemic load with plasma adiponectin in diabetic women and investigate the modification effect of obesity.RESEARCH DESIGN AND METHODS -We conducted a cross-sectional analysis in 902 women with type 2 diabetes from the Nurses' Health Study. Dietary information was obtained using semiquantitative food frequency questionnaires. RESULTS -After adjustment for age, smoking, alcohol consumption, physical activity, aspirin use, HbA 1c , history of hypertension and hypercholesterolemia, and postmenopausal hormone use, intakes of cereal fiber and fruit fiber (P for trend ϭ 0.002 and 0.036, respectively) were significantly associated with an increasing trend of plasma adiponectin concentrations. Further adjustment for BMI did not appreciably change the associations for cereal fiber but attenuated the associations for fruit fiber. Adiponectin concentrations were 24% higher in the highest compared with the lowest quintile of cereal fiber. Dietary glycemic load and glycemic index were significantly associated with lower plasma adiponectin levels, after adjustment for BMI and other covariates (P for trend ϭ 0.01 and 0.03, respectively). The percent differences in adiponectin concentration between the highest and the lowest quintiles of dietary glycemic load and glycemic index were 17 and 18%, respectively. The associations between dietary factors and plasma adiponectin were consistent across lean (BMI Ͻ25 kg/m 2 ), overweight (25 Յ BMI Ͻ30 kg/m 2 ), and obese subjects (BMI Ն30 kg/m 2 ).CONCLUSIONS -Our data indicate that dietary cereal fiber and glycemic load/index are associated with the circulating adiponectin concentration. Such associations were not modified by obesity status.
Diabetes Care 29:1501-1505, 2006A diponectin is an adipose-secreted cytokine that circulates at a high concentration in blood (1). It is well documented that adiponectin improves insulin sensitivity through reducing blood free fatty acids, enhancing insulin action, stimulating glucose utilization, increasing hepatic fatty acid oxidation, and decreasing hepatic fatty acid synthesis (2-5). Plasma adiponectin concentrations have been inversely associated with the risks of diabetes and cardiovascular diseases in the general population (6,7). Circulating adiponectin was found to be associated with a better lipid profile, better glycemic control, and reduced inflammation in diabetic patients from our cohorts (8,9) and another population (10). Furthermore, we have found that both blood adiponectin concentrations and the variability in the adiponectin gene might affect the risk of diabetes-related cardiovascular diseases (11,12). These data together suggest that adiponectin is an important target for management of diabetes, especially in regard to cardiovascular complications.Recently, we found that dietary cereal fiber and glycemic load were associated with plasma adiponectin in diabetic men (13). A previous study had documented that blood adiponectin levels were dif...