Nine studies were included in the review: three cohort studies (n=75,593); three case-control studies (n=3,307); and three cross-sectional studies (n=10,074). Four studies were rated as being of high quality, three moderate and two low quality. All but two studies adjusted for age and smoking in their analyses. The funnel plot indicated possible publication bias.
A high dietary intake of ω-3 fatty acids was associated with a 38% reduction in the risk of late AMD (OR 0.62, 95% CI: 0.48 to 0.82, I2=0%; four studies). Eating fish at least twice a week was associated with a reduction in risk of both early AMD (OR 0.76, 95% CI:0.64 to 0.90, I2=11.5%; six studies) and late AMD (OR 0.67, 95% CI: 0.53 to 0.85, I2=0%; six studies).