Weekend 'Catch-Up' Sleep May Help Kids' Weight
Study: Children Who Don't Get Enough Sleep Have Higher Risk of Obesity, but Sleeping in on the Weekends May Help
Jan. 24, 2011 -- Children who get too little sleep and have irregular school-day sleep schedules are more likely to be obese, especially if they don’t make up for lost sleep on the weekends, a new study finds.
When researchers monitored the sleep patterns of about 300 children between the ages of 4 and 10 for a week, they found that very few slept the recommended amount. The National Sleep Foundation recommends that preschoolers aged 3-5 sleep 11 to 13 hours daily and children aged 5-10 sleep 10 to 11 hours.
Most Kids Sleep 8 Hours
Most children slept about 8 hours, and school-day sleep patterns were not radically different for normal weight, overweight, and obese children.
But obese children did sleep less overall, their sleep schedules were more irregular, and they were less likely to experience “catch-up” sleep on the weekends, University of Chicago professor of pediatrics David Gozal, MD, tells WebMD.
Compared to children who slept about 9 hours a night, children who slept an average of 7 hours and had the most irregular sleep patterns had a fourfold greater risk of being obese, Gozal says.
Kids with irregular weekday sleep schedules who made up for lost sleep during the weekend were less likely to be obese than children who did not get the catch-up sleep.
The research was published today in the journal Pediatrics.
“Their risk was still higher than kids who got enough sleep and had regular sleep patterns, but it was less than when short sleep was combined with irregular sleep,” he says.
Poor Sleepers Had More Metabolic Risk
Although earlier studies have linked insufficient sleep and poor sleep habits to obesity in children, most have relied on parental recall to determine how much sleep kids were getting.
Gozal says parents tend to overestimate the amount of sleep their children get during the night by 60 to 90 minutes.
The study is the first to actually monitor sleep in children over the course of a week.
The children wore a wrist device called an Actiwatch, which is similar to a wristwatch but measures and records motion.
Study participants slept, on average, about eight hours a night, whether they were normal weight, overweight, or obese. But obese children slept less on weekends, suggesting that they were not making up for missed sleep during the week, Gozal says.
The researchers also took blood samples from about half of the children to measure metabolic and inflammatory risk factors for heart disease and diabetes such as glucose, insulin, cholesterol, and triglycerides.
Shorter overall sleep duration and irregular sleep were associated with a greater prevalence of these risk factors.
The findings do not prove that sleeping too little or having a poor sleep routine are direct contributors to obesity and the development of metabolic risk factors for disease.