Background and objectives: The consumption of fish and long chain omega-3 polyunsaturated fatty acids (n-3 PUFA) may influence the risk of all-cause mortality, but the findings have been inconsistent. The current systematic review and meta-analysis is to clarify the association between fish and long chain n-3 PUFA consumption with risk of all-cause mortality.
Methods and study design: Studies published before March 2017 were identified through electronic searches using PubMed, Scopus and Web of Science database. We included prospective cohort studies that reported relative risks with 95% CI of all-cause mortality for fish and long chain n-3 PUFA consumption. Results were combined using a random effects model.
Results: Twenty-three prospective cohorts with a total of 1,035,416 participants were included. Twenty-two pooled studies involving 985,126 participants indicated that fish intake was associated with 6% (RR: 0.94; 95% CI: 0.90, 0.98) reduction in risk of all-cause mortality. Six studies with 430,579 participants investigated the association between long chain n-3 PUFA and all-cause mortality risk, the relative risk for highest versus lowest category was 0.86 (95% CI: 0.80, 0.93). Doseresponse analysis suggested that the risk of all-cause mortality was reduced by 7% (RR: 0.93; 95% CI: 0.88, 0.99) for every 0.2 g per day increment in long chain n-3 PUFA consumption.
Conclusions: Current meta-analysis indicates that both fish and long chain n-3 PUFA consumption are inversely associated with risk of all-cause mortality. These findings could have public health implications with regard to lowering risk of all-cause mortality through dietary interventions.