The 2005 Dietary Guidelines for Americans and insulin resistance in the Framingham Offspring Cohort.

OBJECTIVE The aim of this study was to examine the relationship between a diet consistent with the 2005 Dietary Guidelines for Americans (DGA), as assessed by the 2005 Dietary Guidelines for Americans Adherence Index (DGAI), and measures of insulin resistance in the Framingham Heart Study Offspring Cohort. RESEARCH DESIGN AND METHODS We examined cross-sectional associations between DGAI score and degree of insulin resistance as measured by the homeostasis model assessment of insulin resistance (HOMA-IR) and fasting insulin in 3,082 participants in the Framingham Offspring Cohort fifth examination (January 1991-June 1995). RESULTS Participants in the highest quintile category of the DGAI score had significantly lower HOMA-IR than those in the lowest quintile category after adjusting for age, sex, and waist circumference (6.4 compared with 6.7, P = 0.04). We observed a significant interaction between DGAI score and sex, and upon stratification, the association appeared to be largely confined to women (5.9 compared with 6.6, P < 0.001). No association was apparent in men (7.2 compared with 7.1, P = 0.30). Similar associations were evident between the DGAI score and fasting insulin. CONCLUSIONS Consumption of a diet consistent with the 2005 DGA may be an effective means to limit insulin resistance in women.