The influence of FADS1 and ELOVL2 genetic polymorphisms on polyunsaturated fatty acid composition in response to fish oil supplementation

Background: Unhealthy dietary habits have been recognized as key contributors to the increasing incidence of non-communicable diseases. Among the healthy nutrients studied, omega-3 fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have received considerable attention for their benefits in cardiovascular health and inflammation management. Their synthesis is regulated by enzymes encoded by FADS1 and ELOVL2 genes. Single nucleotide polymorphisms (SNPs) within these genes can modify the efficiency of fatty acid conversion, thereby influencing the Omega-3 Index, which reflects omega-3 status, particularly EPA and DHA. This study aimed to assess the impact of FADS1 (rs174537) and ELOVL2 (rs953413) polymorphisms on the effects on fatty acids profiles of fish oil supplementation in healthy individuals. Methods: Eighty-six healthy adults aged 20–70 participated in a quasi-experimental intervention involving a 4-week fish oil supplementation rich in EPA and DHA. Dried-blood spots (DBS) were collected before and after the intervention to evaluate lipid profiles. Genotyping for FADS1 and ELOVL2 SNPs was performed using high-resolution melting analysis. Results: Post-supplementation, the percentage of EPA and DHA increased significantly (p < 0.001), leading to an improved Omega-3 Index. Baseline omega-3 percentages did not differ significantly between FADS1 and ELOVL2 genotypes. However, individuals with the ELOVL2 minor allele (GA + AA) genotype benefited more from the fish oil supplementation with increased EPA and DBS Omega-3 Index, indicating a more favorable metabolic response. Conclusions: Genetic variability may influence the metabolic response to fish oil supplementation. These findings underscore the importance of personalized nutrition strategies to optimize health outcomes and prevent non-communicable diseases.