The role of n-3 long chain polyunsaturated fatty acids (LC n-3 PUFA) in reducing the risk of type 2 diabetes (T2DM) is not well established. The synthesis of LC n-3 PUFA requires fatty acid desaturase enzymes, which are encoded by the FADS gene. It is unclear if FADS polymorphism and dietary fatty acid intake can influence plasma or erythrocyte membrane fatty acid profile and thereby the risk of T2DM. Thus, the aim of this systematic review was to assess the current evidence for an effect of FADS polymorphism on T2DM risk and understand its associations with serum/erythrocyte and dietary LC n-3 PUFA. A systematic search was performed using PubMed, Embase, Cochrane and Scopus databases. A total of five studies met the inclusion criteria and were included in the present review. This review identified that FADS polymorphism may alter plasma fatty acid composition and play a protective role in the development of T2DM. Serum and erythrocyte LC n-3 PUFA levels were not associated with risk of T2DM, while dietary intake of LC n-3 PUFA was associated with lower risk of T2DM in one study only. The effect of LC n-3 PUFA consumption on associations between FADS polymorphism and T2DM warrants further investigation.
Keywords: FADS polymorphism; omega-3 fatty acids; type 2 diabetes.