Manganese intake is inversely associated with depressive symptoms during pregnancy in Japan: Baseline data from the Kyushu Okinawa Maternal and Child Health Study

Background: One epidemiological study in Canada has addressed the association between zinc intake and depressive symptoms during pregnancy while another epidemiological study in Korea has examined the association between iron intake and depressive symptoms during pregnancy. The present cross-sectional study in Japan examined the association between intake of zinc, magnesium, iron, copper, and manganese and depressive symptoms during pregnancy. Methods: Study subjects were 1745 pregnant women. Dietary intake during the preceding month was assessed using a self-administered diet history questionnaire. Depressive symptoms were defined as a score >= 16 on the Center for Epidemiologic Studies Depression Scale. Adjustment was made for age, gestation, region of residence, number of children, family structure, history of depression, family history of depression, smoking, secondhand smoke exposure at home and at work, employment, household income, education, body mass index, and intake of saturated fatty acids, eicosapentaenoic acid plus docosahexaenoic acid, calcium, vitamin D, and isoflavones. Results: In crude analysis, significant inverse associations were observed between intake levels of zinc, magnesium, iron, copper, and manganese and the prevalence of depressive symptoms during pregnancy. After adjustment for confounding factors, only manganese intake was independently inversely associated with depressive symptoms during pregnancy: the adjusted prevalence ratio between extreme quartiles was 0.74 (95% confidence interval:0.56-0.97, P for trend=0.046). Limitations: Information was obtained between the 5th and 39th week of pregnancy. Conclusions: The current cross-sectional study of Japanese women demonstrated higher manganese intake to be independently associated with a lower prevalence of depressive symptoms during pregnancy.