Association between maternal fermented food consumption and infant sleep duration: The Japan Environment and Children's Study

BACKGROUND: Evidence indicates that human circadian rhythm is affected by the intestinal microbiota, and establishment of the circadian rhythm begins during fetal development. However, the relationship between maternal fermented food intake and infant sleep duration has not been previously investigated. In this study, we examined whether dietary consumption of fermented food during pregnancy is associated with infant sleep duration at 1 year of age. METHODS: This birth cohort study used data from a nationwide government-funded study called The Japan Environment and Children’s Study (JECS). After exclusions from a dataset comprising 104,065 JECS records, we evaluated 72,624 mother-child pairs where the child was 1 year old. We investigated the association between dietary intake of fermented foods during pregnancy and infant sleep duration of less than 11 h at 1 year of age. RESULTS: Multivariable logistic regression showed that maternal intake of fermented food, especially miso, during the pregnancy was independently associated with reduced risk of infant sleep duration of less than 11 h. CONCLUSIONS: Further research, including interventional studies, is warranted to confirm the association between consumption of fermented foods during pregnancy and sufficient infant sleep duration. TRIAL REGISTRATION: UMIN000030786.