Association between polyunsaturated fatty acids intake and insulin resistance in Brazilian adolescents (ERICA Study).

Objective: Some studies have proposed a beneficial effect of polyunsaturated fatty acid (PUFA) intake with regard to insulin sensitivity. The aim of this study was to estimate the energy percentage and the daily PUFA intake to investigate the association between PUFAs and insulin resistance in a large sample of Brazilian adolescents.

Methods: We evaluated 37 023 adolescents ages 12 to 17 y, who were participants in ERICA (Study of Cardiovascular Risk in Adolescents). Energy percentage and PUFA daily intake were extracted from a 24-h dietary recall. The mean daily intake of total fat, median, and the respective 95% confidence intervals (95% CI) of daily intake of linoleic acid (LA), α-linolenic acid (ALA) and the ratio of LA to ALA were estimated according to sociodemographic variables. Associations of PUFA and markers of glucose homeostasis were analyzed by Poisson regression model.

Results: Mean total fat intake was 30.1% of energy (95% CI, 29.9-30.4). Most participants met the current recommended values of PUFA and LA/ALA ratio ranging from 5:1 to 10:1 (80.9%, 95% CI, 79.8-81.8). ALA intake was inversely associated with higher waist circumference (prevalence ratio [PR], 0.996; 95% CI, 0.994-0.998). LA/ALA ratio ≥9:1 was significantly associated with higher levels of homeostasis model assessment of insulin resistance (HOMA-IR; PR, 1.01; 95% CI, 1.006-1.02), and ratio >10:1 also showed significant association with higher levels of HOMA-IR (PR, 1.02; 95% CI, 1.01-1.03) and glycated hemoglobin (PR, 1.14; 95% CI, 1.04-1.26). These associations remained significant after adjustment.

Conclusion: Promotion of ALA intake and balanced LA/ALA ratio should be considered as a possible health strategy aimed at contributing to better control of glucose homeostasis and insulin resistance in adolescents.