RESUMEN
OBJECTIVE: The aim of the present study was to investigate the association of diet quality with fasting glycemia, insulinemia, and insulin resistance in a cross-sectional sample of adults from families at high risk for type 2 diabetes mellitus (T2DM) from six European countries, taking into account their socioeconomic status (SES). METHODS: Baseline data from non-diabetic adults from the Feel4 Diabetes study were used and diet was assessed by the Healthy Diet Score (HDS). Insulin resistance (IR) was determined by homeostasis model assessment of IR (HOMA-IR). Sociodemographic and lifestyle characteristics were assessed through standardized questionnaires. Multiple linear regressions were adjusted for many confounders, in the total sample and by SES category. RESULTS: In 1980 adults, the third tertile of diet quality was inversely associated with insulin levels (-1.48; 95% confidence interval [CI], -2.34 to 0.62), and HOMA-IR (-0.33; 95% CI, -0.57 to 0.09), yet with no statistically significant results for glucose levels. In the SES subgroup analysis, in the high SES group, both second and third diet score tertiles were inversely associated with insulin levels (-1.81; 95% CI, -2.66 to 0.95) and HOMA-IR values (-0.45; 95% CI -0.69 to 0.21), independent of age, sex, smoking and body mass index. No such associations were observed for glucose levels in the high SES group and for all indices in the low SES group. CONCLUSION: In adults from families at high risk for T2DM, higher diet quality was negatively associated with fasting insulin levels and IR, only in the high SES group and not in the low SES group. Future larger studies may be able to explore further this association, as well as the potential factors that mitigate its strength in the low SES groups.