According to a study from The Ohio State University College of Public Health, preschool children with early weekday bedtimes (by 8 p.m) are half as likely as children with late bedtimes (after 9 p.m.) to be obese adolescents. The study was published in the The Journal of Pediatrics.
“For parents, this reinforces the importance of establishing a bedtime routine,” said Sarah Anderson, lead author and associate professor of epidemiology in a news release. “It’s something concrete that families can do to lower their child’s risk and it’s also likely to have positive benefits on behavior and on social, emotional and cognitive development.”
Study results also arm pediatricians with scientifically based advice for parents, she said.
Poor sleep, especially short sleep duration, is a proven risk factor associated with increased risk for obesity. In fact, bedtimes have a greater impact on children’s sleep duration than wake times; are more modifiable than wake times; and are the likely behavioral target of clinicians and parents.
The recent study, “Bedtime in Preschool-Aged Children and Risk for Adolescent Obesity,” aimed to flip previous studies by showing that earlier bedtimes lower risk for adolescent obesity and that lowered risk is impacted by maternal sensitivity.
For the new study, Anderson and colleagues used records gathered from 977 young children enrolled in 1991 in the Study of Early Child Care and Youth Development. The researchers divided bedtimes into three groups: 8 p.m. or earlier; between 8 p.m. and 9 p.m.; and after 9 p.m. At the time when mothers reported typical weekday bedtimes, the children were all about 4 ½ years old.
The researchers later associated the young children’ bedtimes to wights of the children at age 15.
Researchers found that the prevalence of adolescent obesity was 10% for children who went to bed at 8 p.m.; 16% for children whose bedtimes were between 8 and 9 p.m.; and 23%, for those who went to bed after 9 p.m.
Dr. Anderson and colleagues also examined videotaped playtimes between mothers and the preschool children to observe if the emotional climate in which parents establish bedtime routines could impact the adolescent obesity result. Observations indicated that regardless of the quality of the maternal-child relationship, children who went to bed at the latest hours and whose mothers had the lowest interaction sensitivity scores, were found at the highest risk for obesity.
The results of the study also revealed that later bedtimes were more common in non-white children, in children whose mothers had less education, and children who lived in lower-income households.
“Having the same routine every night is important so children know what to expect,” said Dr. Meena Khan, a sleep medicine specialist at The Ohio State University Wexner Medical Center. “Kids do well with a schedule and a routine. They do better with that than one night they go to bed at 8 p.m., another night they go to bed at 9 p.m.”
Putting children early in bed doesn’t assure they will fall into deep sleep immediately, but creating a regular bedtime routine makes it more likely that children will get the amount of sleep they need, Anderson said.
According to previous studies, most young children are biologically pre-programmed to be ready for sleep well before 9 p.m. anyway.
“It’s important to recognize that having an early bedtime may be more challenging for some families than for others,” Anderson said. “Families have many competing demands and there are tradeoffs that get made. For example, if you work late, that can push bedtimes later in the evening.”