Objectives: The association between fish consumption and the risk of breast cancer has not been established yet. Results from epidemiological studies are inconsistent. We conducted a meta-analysis to examine the association between fish consumption and the risk of breast cancer.
Methods: We identified eligible studies in Medline and EMBASE up to February 2015 and the reference lists of original studies and review articles on this topic. Summary relative risks with their 95% confidence intervals were calculated with a random-effects model.
Results: We identified 27 studies eligible for analysis. The summary relative risk of breast cancer for the highest consumption of fish compared with the lowest was 0.96 (95% CI = 0.87-1.07), with evidence of heterogeneity (Q = 69.09, p < 0.001, I2 = 68.0%). Four studies investigated lean fish consumption and revealed that there was a small increase in the risk of breast cancer (summary RR = 1.09, 95% CI = 1.00-1.19). As only four studies were included in the subgroup analysis, results must be interpreted with caution.
Conclusions: The overall current literature on fish consumption and the risk of breast cancer suggested no association. Further well-designed prospective studies are needed to explore fish consumption in relation to breast cancer risk.
Keywords: Breast cancer. Fish consumption. Systematic review. Meta-analysis. Relative risks.