Association between unhealthy dietary behaviors and sleep disturbances among Japanese adolescents: a nationwide representative survey

Purpose: Dietary behaviors and sleep are important lifestyle factors to protect adolescent health. However, little is known about how dietary behaviors are related to sleep disturbances. The purpose of this study was to conduct a large-scale survey among Japanese adolescents to verify the association between unhealthy dietary behaviors and sleep disturbances. Methods: This study included 65,688 and 99,581 students enrolled in 140 and 120 randomly selected junior and senior high schools, respectively. A total of 85,931 self-administered questionnaires were collected from 79 junior and 77 senior high schools from 2014 to 2015. The survey included questions on sleep patterns, dietary behaviors, alcohol consumption, and smoking, as well as questions on mental health. For dietary behaviors, we adopted the items on meal habits in the National Health and Nutrition Survey including, the frequency of eating breakfast, the frequency of family meals, and subjective diet quality. We performed a multivariate analysis on the relationship between the dietary behaviors and sleep disturbance. Results: Data from 84,988 questionnaires were analyzed. Boys and girls with less healthy dietary behaviors had a significantly higher prevalence for each sleep disturbance. Subjective sleep quality and insomnia were significantly associated with breakfast frequency, family meal frequency, and diet quality. Short sleep duration was significantly associated with breakfast frequency and family meal frequency, but not with subjective diet quality. Conclusions: Our study suggested that sleep and dietary behaviors affect one another. Those involved in public health education should encourage adolescents to establish healthy sleep patterns as well as healthy dietary behaviors.