A later bedtime linked with obesity for children under 6, study says

(CNN)A new study has linked a later bedtime with an increased risk of obesity for kids -- although the researchers say parents shouldn't rush to put their preschoolers to sleep earlier as a result.

Instead, concerned moms and dads should focus on maintaining a regular routine when it comes to scheduling meal and bed times, said Dr. Claude Marcus, a professor of pediatrics at the Karolinska Institute in Sweden and an author of the study, which published Tuesday in the journal Pediatrics.
The research, which was part of a wider study on obesity, focused on 107 children in Sweden, with 64 of the children having a parent who classified as overweight or obese.
    The researchers monitored each child's weight, height and waist circumference from ages one to six; all of the children had similar measurements when the study started. Sleep was measured for seven consecutive days once a year for the length of the study by using a tracker worn on the child's wrist.
      They found that children who habitually went to sleep late -- defined by the researchers as past 9 p.m. -- had a wider waist and higher BMI (body mass index) by the end of the study.