Background. An ecological analysis found that the docosahexaenoic acid content in mother's milk and seafood intake were inversely correlated with postpartum depression. This prospective study investigated the relationship of consumption of selected high-fat foods and specific types of fatty acids with the risk of postpartum depression.
Method. The subjects were 865 Japanese women. Dietary data were obtained from a self-administered diet history questionnaire during pregnancy. The Edinburgh Postnatal Depression Scale (EPDS) was used for the evaluation of postpartum depression. Adjustment was made for age, gestation, parity, cigarette smoking, family structure, family income, education, changes in diet in the previous month, season when data at baseline were collected, body mass index, time of delivery before the second survey, medical problems in pregnancy, baby's sex and baby's birthweight.
Results. The percentage of women with high depression scores was 14·0%. No evident dose–response associations were observed between intake of fish, meat, eggs, dairy products, total fat, saturated fatty acids, monounsaturated fatty acids, n-3 polyunsaturated fatty acids, n-6 polyunsaturated fatty acids, linoleic acid, α-linolenic acid, arachidonic acid, eicosapentaenoic acid or docosahexaenoic acid and the ratio of n-3 to n-6 polyunsaturated fatty acids and the risk of postpartum depression. However, there was an inverted J-shaped relationship between intake of n-3 polyunsaturated fatty acids and docosahexaenoic acid and the risk of postpartum depression.
Conclusions. This study failed to substantiate a clear inverse relationship between fish and n-3 polyunsaturated fatty acid intake and postpartum depression. Further investigations are needed to determine whether fish and n-3 polyunsaturated fatty acid consumption is preventive against postpartum depression.