Although common in Western countries depression appears to be virtually absent in countries where people eat a lot of fish. This is thought to be due to Omega-3 fatty acid in seafood. Researchers from the University of Bristol studied the effects of seafood consumption on prenatal depression in a sample of 9,960 pregnant women. Compared with pregnant women who ate 3 or more servings of seafood per week those who ate no seafood were about 50% more likely to report depression. Depression during pregnancy is harmful to both mother and child, however, pregnant women are currently warned to limit seafood consumption due to its mercury content.
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