Children who sleep less than their peers may be at greater risk for abnormal blood glucose levels and other metabolic problems.
Researchers studied the sleep patterns of 308 children ages 4-10, half of them overweight or obese. They used wrist monitors to measure their sleep time over seven days, and did blood tests for cardiovascular risk indicators like glucose, lipids, insulin, and Creactive protein.
The study, published in the February issue of Pediatrics, found that obesity and abnormal blood tests were four times as common in children who slept the least, and three times as common in those who used the weekend to catch up on sleep lost during school days.
“We can't rule out that obese children first became obese and then started sleeping less,” said Dr. David Gozal, the senior author. “But it's unlikely.”
Among all children, obese or not, shorter sleep and greater variability in sleep patterns were more likely to be associated with abnormal blood tests. The researchers conclude that irregular sleep by itself may be a risk factor for metabolic problems.
"We sacrifice sleep to whatever else we do,” said Gozal, a professor of pediatrics at the University of Chicago. “But as parents we should be very attentive to preserving the treasure that is sleep — it means health for children's brains and their bodies, their happiness and their well-being.”