The integrative panel of fatty acid desaturase-2 (FADS2) rs174583 gene polymorphism and dietary indices (DQI-I and HEI) affects cardiovascular risk factors among obese individuals

BACKGROUND: Recent studies have shown that dietary intakes and gene variants have a critical role in the obesity related comorbidities. This study aimed to evaluate the effects of the interactions between Fatty acid desaturase 2 (FADS2) gene rs174583 polymorphism and two dietary indices on cardiometabolic risk factors. METHODS: This cross-sectional study was carried out on 347 obese adults aged 20-50 years old in Tabriz, Iran. Healthy eating index (HEI) and Diet quality index-international (DQI-I) were evaluated by a validated semi-quantitative 147-item Food frequency questionnaire (FFQ). Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine FADS2 gene variants. Multivariate analysis of covariance (MANCOVA) was used to identify gene-diet interactions on metabolic parameters. RESULTS: Waist circumference (WC) and serum triglyceride (TG) levels were significantly higher among carriers of TT genotype of FADS2 gene (P < 0.05). In addition, the interactions between FADS2 gene rs174583 polymorphism and DQI-I had significant effects on weight (P (interaction) = 0.01), fat mass (P (interaction) = 0.04), fat free mass (P (interaction) = 0.03), and Body mass index (BMI) (P (interaction) = 0.02); the highest level of these parameters belonged to TT carriers. Similarly, the interactions between FADS2 gene variants and HEI had significant effects on insulin (P (interaction) < 0.001), Homeostasis model assessment of insulin resistance (HOMA-IR) (P (interaction) < 0.001), Quantitative insulin check index (QUICKI) (P (interaction) = 0.001), and alpha Melanocyte stimulating hormone (α-MSH) (P (interaction) = 0.03). CONCLUSION: In this study, for the first time, we reported the effects of gene-diet interactions on metabolic traits. Compliance with dietary indices (DQI-I and HEI) ameliorated the adverse effects of gene variants on metabolic risk factors, especially in heterogeneous genotypes. Further prospective cohort studies are needed to confirm these results. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12902-023-01289-3.