After pooling all the European data together, a significant association emerged between those eating the most fish and a 17 percent reduction in depression risk compared with those eating the least.
When the researchers looked specifically at gender, they found a slightly stronger association between high fish consumption and lowered depression risk in men (20 percent).
Among women, the associated reduction in depression risk was 16 percent.
“Higher fish consumption may be beneficial in the primary prevention of depression. Future studies are needed to further investigate whether this association varies according to the type of fish,” the authors noted in a paper which appeared online in the Journal of Epidemiology & Community Health.
Several previous studies have looked at the possible role of dietary factors in modifying depression risk, but the findings have been inconsistent and inconclusive.
The researchers pooled the data from relevant studies published between 2001 and 2014 to assess the strength of the evidence on the link between fish consumption and depression risk.
After trawling research databases, they found 101 suitable articles, of which 16 were eligible for inclusion in the analysis. These 16 articles included 26 studies, involving 150,278 participants.
“The high-quality protein, vitamins, and minerals found in fish may help stave off depression while eating a lot of fish may be an indicator of a healthy and more nutritious diet,” the researchers suggested.
Depression affects an estimated 350 million people worldwide, and is projected to become the second leading cause of ill health by 2020.