The association of n-3 fatty acids with serum High Density Cholesterol (HDL) is modulated by sex but not by Inuit ancestry

ObjectiveTo explore the association between dietary n-3 fatty acids and serum lipids in a population with a high intake of marine food. Specifically to test interaction with sex and ethnicity.MethodsInformation was obtained from 2280 Inuit who participated in a countrywide health survey in Greenland in 2005-2009. n-3 intake was estimated from an FFQ and analyses of Red Blood Cell (RBC) membranes. Serum total, HDL and LDL cholesterol and triglyceride were analysed. Obesity was measured. Information on ethnicity, smoking, alcohol consumption, and physical activity was obtained from an interview.ResultsIn linear regression models adjusted for age, sex, obesity, ethnicity, alcohol, and smoking serum HDL, LDL and triglyceride were associated with n-3 intake estimated as eicosapentaenoic acid (EPA) in RBC membranes. For HDL the interaction between EPA and sex was significant (p < 0.001). No significant interactions were observed for EPA and ethnicity.ConclusionA positive association of EPA with serum HDL and LDL and a negative association with triglyceride was observed among both men and women. For HDL, the association was stronger for men. The association of EPA with serum HDL was similar among Inuit with full Inuit ancestry and those with part Inuit ancestry. Diet and overweight are both realistic candidates for a population based intervention against dyslipidemia. Further studies of ethnic differences in the effect of n-3 fatty acids on cardiovascular risk factors are recommended.

► EPA was directly associated with serum HDL and LDL in male and female Inuit. ► EPA was negatively associated with triglyceride in male and female Inuit. ► For HDL, the association was stronger for men. ► EPA/HDL association was independent of the degree of Inuit ancestry. ► Diet and overweight are both candidates for intervention against dyslipidemia.