Early bedtime may fight weight gain

VITAL SIGNS

Preschool children who are in bed by 8 pm are far less likely to be obese during adolescence than children who stay up late, a study has found. Their risk of teenage obesity is half the risk faced by preschoolers who stay up past 9 pm.

The research analysed data gathered on nearly 1,000 children born in 1991 whose bedtimes were recorded when they were 4 1/2, and whose height and weight were recorded at age 15. The children were part of the Study of Early Child Care and Youth Development, done under the auspices of the Eunice Kennedy Shriver National Institute
of Child Health and Human Development.

Among the children who were in bed by eight pm, 10% were obese as teens,
compared with 16% of those who went to bed between eight and nine and 23% of those who went to bed after nine, according to the study, published in The Journal of Pediatrics.

The researchers adjusted for factors such as socioeconomic status, maternal obesity and parenting style, and still found that the children who went to bed by 8 pm were at less than half the risk of teenage obesity as those who were up past nine, said Sarah E Anderson, the paper’s lead author and an associate professor of epidemiology at the Ohio State University College of Public Health in Columbus.

Although the study does not prove that early bedtimes protect against obesity, Sarah said, “there is a great deal of evidence linking poor sleep, and particularly short sleep duration, to obesity.”