Supplementary Material for: PLASMA FATTY ACID BIOMARKERS OF DAIRY CONSUMPTION ARE ASSOCIATED WITH SEX-DEPENDENT EFFECTS ON METABOLIC SYNDROME COMPONENTS IN MEXICAN ADOLESCENTS

Introduction: During adolescence, dairy product intake has shown conflicting associations with Metabolic Syndrome (MetS) components, which are risk factors for cardiovascular disease. Objective: This study aims to investigate the association between plasma fatty acids (FAs) C15:0, C17:0 and t-C16:1n-7, as biomarkers of dairy intake, with MetS and its components in Mexican adolescents. Methods: A sample of 311 participants from the ELEMENT cohort were included in this cross-sectional analysis. FA concentrations were measured in plasma, as a percentage of total FA. We used quantile regression models stratified by sex to evaluate the association between FA quantiles and MetS components, adjusting for age, socioeconomic status, sedentary behavior, BMI z-score, pubertal status, and energy intake. Results: We found significant associations between dairy biomarkers and the median of MetS variables. In females, t-C16:1n-7 was associated with a decrease of 2.97 cm in WC (Q4 vs Q1; 95% CI: -5.79, -0.16). In males, C15:0 was associated with an increase of 5.84 mm/Hg in SBP (Q4 vs Q1; CI: 1.82, 9.85). For HDL-C we observed opposite associations by sex. C15:0 in males was associated with decreased HDL-C (Q3 vs Q1: β= -4.23; 95% CI: -7.98, -0.48), while in females C15:0 and t-C16:1n-7 were associated with increased HDL-C (Q3 vs Q1: β= 4.75; 95% CI: 0.68, 8.82 and Q4 vs Q1: β=6.54; 95% CI: 2.01, 11.07), respectively. Additionally, in both sexes different levels of C15:0, C17:0, and t-C16:1n-7 were associated with increased triglycerides (TG). Conclusions: Our results suggest that adolescent dairy intake may be associated in different directions with MetS components, and that associations are sex-dependent.