Having a regular, age-appropriate bedtime and getting sufficient sleep from early childhood may be important for healthy body weight in adolescence, according to researchers at Penn State. In a national study of urban households, the researchers identified groups of children by bedtime and sleep routines and tested longitudinal associations for each group with adolescent body mass index (BMI). Their data suggest that childhood bedtime and sleep routine groups predict adolescent sleep patterns and BMI. One-third of children consistently adhered to age-appropriate bedtimes for ages 5 through 9. Those who had no bedtime routine at age 9 had shorter self-reported sleep duration and higher BMI at age 15, when compared to those children with age-appropriate bedtimes (after adjusting for age 3 BMI). Researchers analyzed longitudinal data from the Fragile Families and Child Wellbeing Study, a national cohort from 20 United States cities, with 2,196 subjects.
Childhood bedtime and sleep routines were assessed by mothers’ reports of their children’s presence and timing of bedtimes, adherence to bedtimes, and habitual sleep duration at ages 5 and 9. At age 15, these adolescents reported their height and weight, which were used to calculate BMI. Bedtime should provide enough of a “window” for the child to get an appropriate amount of sleep, even if the child doesn’t fall asleep right away. This study supports existing pediatric recommendations that having a regular and age-appropriate bedtimes is important for children’s health, said lead author Soomi Lee, now assistant professor of aging studies in the College of Behavioral and Community Sciences at the University of South Florida. Dr. Lee, who was at Penn State at the time of the study, received her graduate degree in human development and family studies, and her post-doctoral degree in Biobehavioral Health, at Penn State.
Additionally, the study shows continuity in sleep behaviors, in that those who had most optimal bedtime and sleep routines during childhood also had sufficient sleep duration in adolescence, whereas those with suboptimal bedtime and sleep routines had insufficient sleep duration in adolescence, she said. Overall, the research highlights the importance of educating parents in bedtime parenting, especially for those in low-income households as Dr. Lee keeps commenting: “In our sample that includes a large proportion of low-income, low-education, and ethnic minority households, only less than one third of children had age-appropriate bedtime routines at age 5 and 9. This raises a concern about development and health of children in disadvantaged households. Future family interventions may need to include parental educations about sleep health, particularly focusing on parents with low income and low education.”
Co-author Orfeu Buxton, professor of biobehavioral health at Penn State, and director of the Sleep, Health, and Society Collaboratory at Penn State, explained: “We think sleep affects physical and mental health and the ability to learn. Parenting practices in childhood affect physical health and BMI in the teenage years. Developing a proper routine in childhood is crucial for the future health of the child. Bedtimes should be determined by various factors, such as when the child has to wake up based on the time it takes for that child to get ready for school, and the time it takes to get to school, as well as the school start time. School start times aren’t determined by parents, but bedtimes and bedtime routines can be adjusted by parents. Giving children the time frame to get the appropriate amount of sleep is paramount, as achieving recommended duration of sleep can have an impact on BMI in adolescent years, according to our findings”.
Additionally, future studies should focus on whether childhood sleep behavior interventions promote healthier sleep and weight in later life course stages.
- Edited by Dr. Gianfrancesco Cormaci, PhD, specialist in Clinical Biochemistry.
Scientific references
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