Dietary glycemic index, glycemic load, and cardiovascular disease risk factors: Tehran Lipid and Glucose Study.

BACKGROUND Data available on the effect of quality (glycemic index [GI]) and quantity (glycemic load [GL]) of carbohydrates on the risk factors of cardiovascular disease (CVD) are inconsistent. The objective of this study was to examine the association between dietary GI, GL, and CVD risk factors among Tehranian adults, the participants of the Tehran Lipid and Glucose Study. METHODS This population- based cross-sectional study was conducted on 2457 subjects (46% men and 54% women), aged 19 to 84 years. Dietary GI and GL were measured using a validated 168- item semiquantitative food frequency questionnaire. Anthropometrics, blood pressure, fasting blood glucose, and lipid profiles were measured. RESULTS The mean intakes of GI and GL were 68.3 and 244.8, respectively. Rice (26.6%) and bread (19.0%) were the major contributors to dietary GI and GL, respectively. Higher dietary GI and GL were associated with high intakes of carbohydrate, fiber, refined grain, fruits, simple sugar, snack, and desserts. After adjustment for lifestyle and dietary variables, a higher dietary GI was positively associated with triglycerides and high-density lipoprotein (HDL) cholesterol concentrations among obese subjects. Dietary GL was positively associated with fasting and 2-h blood glucose among nonobese subjects, after adjustment for confounders.   CONCLUSION Dietary GI and GL were associated with a few CVD risk factors, and body mass index levels may modulate these associations.