Fish consumption and n-3 polyunsaturated fatty acids, and risk of hepatocellular carcinoma: systematic review and meta-analysis

Purpose To investigate the association between fish consumption and n-3 polyunsaturated fatty acids (n-3 PUFA) and the risk of hepatocellular carcinoma (HCC). Methods We identified eligible studies in MEDLINE and EMBASE up to July 2014 and the reference lists of original studies and review articles on this topic. Summary relative risks (SRR) with their 95 % confidence intervals (CI) were calculated with a random effects model. Results Eleven studies (three cohort studies, seven retrospective case–control studies, and one nested case–control study) met eligibility criteria. Ten articles investigated fish consumption, two articles investigated n-3 PUFA, and two articles investigated alpha-linolenic acid (ALA). The current data suggest that fish consumption was associated with 35 % reduction in HCC risk (highest vs. lowest category SRRs = 0.65, 95 % CI 0.51–0.79; test for heterogeneity p = 0.057, I 2 = 44.1 %). n-3 PUFA was associated with 51 % reduction in HCC risk (highest vs. lowest category SRRs = 0.49, 95 % CI 0.19–0.79). However, no significant inverse association was found in ALA (SRRs = 0.70, 95 % CI 0.30–1.10). Conclusion Our meta-analysis of observational studies provides evidence that fish consumption and n-3 PUFA has inverse association with the risk of HCC.