Omega-3 and omega-6 fatty acids food intake and metabolic syndrome in adolescents 12 to 17 years old: A school-based cross-sectional study.

BACKGROUND & AIMS: Fatty acids (FAs) of the omega-3 and omega-6 family are considered essential, and adequate intake seems to be associated with lower risk of developing chronic non-communicable diseases. The objective was to evaluate the association of omega-3 and omega-6 FAs dietary intake with the prevalence of MS and its components waist circumference (WC), blood pressure (BP), fasting blood glucose, triglycerides and High Density Lipoprotein - cholesterol (HDL-c) in Brazilian adolescents aged 12-17 years. METHODS: This is a school-based cross-sectional investigation, using data from the Study of Cardiovascular Risks in Adolescents (ERICA), carried out between 2013 and 2014. The following variables were collected and assessed: 1) sociodemographic (sex, age, type of school, school location whether urban or rural and region of the country); 2) food consumption was measured through a 24-h Food Recall (24 hR), and a second 24 hR was applied to 7% of the total sample; 3) anthropometrics (weight, height, WC), BP and biochemical (glycemia, triglycerides and HDL-c) were also assessed. Logistic regression analysis was performed according to gender and age group. RESULTS: A total of 36,751 adolescents participated in the study. The intake of omega-3 FAs in the total population was 1.71 g/day and of omega-6 FAs, 13.56 g/day, with an omega-6/omega-3 ratio of 7.93:1. It was found that higher intake of omega-3 FAs was associated with an 53% lower chance of low HDL-c. For omega-6 FAs, no significant results were found. CONCLUSIONS: The findings indicated an association between omega-3 FAs and HDL-c. More studies are needed to elucidate the effects of omega-6 FAs.

Scientific evidence of the association between oral intake of OMEGA-3 and OMEGA-6 fatty acids and the metabolic syndrome in adolescents: A systematic review.

AIMS: To conduct a systematic review of the literature on the scientific evidence of the oral intake of omega-3 and omega-6 FAs and metabolic syndrome (MS) in adolescents. DATA SYNTHESIS: The study was registered in PROSPERO (number 42020185370). Studies were carried out with adolescents aged 10-19 years, who presented as intervention/exposure the oral intake of omega-3 and/or omega-6 fatty acids (FAs), in the databases PubMed, Scopus, Web of Science, LILACS, CENTRAL, and PQDT Global e BDTD. The tools used to assess the risk of bias were RoB 2.0, Agency for Healthcare Research and Quality (AHRQ), and Newcastle-Ottawa Scale. Fifteen papers retrieved published from 2010 to 2019 were included (n = 3534); nine were randomized studies and controlled clinical trials, four were cross-sectional studies, one was a retrospective cohort study, and one case-control study. No studies have evaluated the effect or association of omega-3 and/or of omega-6 FAs with actual MS, only with its components. The randomized clinical trials identified the effects of omega-3 FA on the decrease in blood pressure (n = 1 out of six), glycemia (n = 2 out of seven), and triglycerides (n = 5 out of eight), and the increase in HDL-c (n = 2 out of eight) considering the comparison between the group that received omega-3 FA and the control group. CONCLUSIONS: Scientific evidence is controversial on the association between oral intake of omega-3 FAs and MS in adolescents, due to the heterogeneity between studies and the divergence of results for the same MS component.