Children who go to bed and wake up an average of 1 hour later on weekends vs. weekdays are more likely to have a higher body fat percentage, fat mass index, BMI and waist-to-hip ratio than children who maintain a consistent bedtime, reports Healio.

“In modern society, the rhythmicity of the circadian clock is often disrupted by social obligations, including work and school schedules,” Lee Stoner, PhD, MPH, of the department of exercise and sport science at the University of North Carolina at Chapel Hill, and colleagues wrote. “Social jet lag is simple to measure and may be a simple target for public health policy.”

Stoner and colleagues analyzed data from 341 children aged 8 to 10 years, recruited from schools in three major cities across New Zealand between April 2015 and April 2016 (50% girls; mean age, 10 years).