By Mary Elizabeth Dallas
So suggests research that compared preschoolers who went to bed at 8 p.m. with same-age kids who had later bedtimes. A team at the Ohio State University College of Public Health found that a bedtime just one hour later seemed to double the likelihood that young children will be obese teens.
"For parents, this reinforces the importance of establishing a bedtime routine," said the study's lead author, Sarah Anderson, an associate professor of epidemiology. "It's something concrete that families can do to lower their child's risk."
The study reviewed data on nearly 1,000 children who were part of a study that followed healthy babies born in 1991 at 10 U.S. locations.
When the children were about 4 years old, they were divided into three groups: those who went to bed by 8 p.m.; those whose bedtime was between 8 p.m. and 9 p.m., and those went to bed later.
Half of the youngsters went to bed between 8 p.m. and 9 p.m. The rest were evenly divided between early and late bedtimes, according to the study published July 14 in the Journal of Pediatrics.
Researchers then looked at the kids' weight at an average age of 15. They found that only 10 percent of kids with the earliest bedtimes were obese teens. That compared to 16 percent of the children with bedtimes between 8 p.m. and 9 p.m., and 23 percent of those who went to bed after 9 p.m.
Most likely to become obese were kids who went to bed latest and whose mothers' interactions with them were observed to be less supportive and more hostile, the researchers found. They said later bedtimes were more common among non-white children who had less-educated mothers and lived in lower-income households.
However, only an association was seen between bedtimes and obesity risk, rather than a cause-and-effect link.
"It's important to recognize that having an early bedtime may be more challenging for some families than for others," Anderson said in a university news release. "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."
The study authors said their findings suggest that household routines for preschoolers are important.