Medically reviewed by Priti Parekh, MD, Susan Kerrigan, MD and Marianne Madsen on January 9, 2023
Obesity doesn’t just kill people–it also costs $1.4 trillion a year in healthcare. Gasp! And it starts with our kids.
Something we probably don’t associate with childhood obesity is late bedtimes. Yup, bedtime can be a daily (or rather nightly) challenge that torments parents the world over.
Previous research shows that kids who get less sleep are more likely to be obese. In a very recent study (published in February 2020), Dr. Claude Marcus, a professor of pediatrics in Sweden, links a later bedtime with an increased risk of obesity for kids. Interestingly, Dr. Marcus reports that in his study, it didn’t matter whether a child slept for more or less hours. The children who went to bed after 9 p.m. were more likely to suffer from obesity and to have a higher BMI than kids who went to bed earlier.
Dr. Nicole Glaser and Dr. Dennis Styne, pediatric endocrinologists in California, commented on this study, saying that although other factors might influence obesity, there was an obvious interaction between sleep and body weight. This is because some of the brain regions involved in regulating sleep and wake cycles also manage eating and fasting behavior.
A new study, conducted in Australia and published in Acta Paediatrica, came to a similar conclusion: kids who go to bed early and who follow a consistent bedtime routine may be at a lesser risk of becoming overweight or obese.
But before you rush to get your kids tucked in early, Dr. Marcus points out that we don’t actually know if this would change anything. He suggests that instead of weight gain being directly caused by later bedtimes, staying up beyond 9 p.m. could point to an overall lifestyle that puts kids at greater risk of being overweight. He also recommends that parents maintain a regular routine for mealtimes and bedtimes.
Dr. Veronica Johnson, a pediatric obesity medicine specialist at UTHealth in Houston says that one shortcoming of Dr. Marcus’ study is that it only tracked the participants’ sleep over seven consecutive days, not taking into consideration how sleep changes over time.
It’s also important to note that kids from different cultural backgrounds sleep differently. They don’t all go to bed at 8 p.m. and don’t all sleep for 11-13 consecutive hours. Sara Harkness, a professor and director of the Center for the Study of Culture, Health, and Human Development at the University of Connecticut has conducted research on children’s activities and bedtimes. Harkness reports that during her research in Spain, she discovered that early bedtimes were not common for young children. However, in the Netherlands, babies and young children were put to bed early (at around 6:30 or 7) and expected to sleep through the night in their own bed.
Getting your kids into bed at a decent hour and starting kids off with good sleep hygiene from an early age may therefore help to prevent obesity and overweight. However, it will ensure that both you and your kids are well rested, which can only be a good thing.
References
- Late Bedtime Linked to Obesity in Children. Here’s What Parents Can Do
- Sleep and Adiposity in Children From 2 to 6 Years of Age
- Late bedtime and body mass index gain in indigenous Australian children in the longitudinal study of indigenous children
- A later bedtime linked with obesity for children under 6, study says
- Kids under 6 who go to bed after 9 p.m. may have a higher risk of obesity
- How parents tackle bedtime around the world
- Early bedtime may help children maintain healthy weight
