USA: A recent study in the journal Obesity has reported that children with earlier wake times and sleep midpoints may gain greater fat mass over a year. However, the researchers add that there is a need for additional studies to determine whether sleep timing may be a modifiable target for the prevention of pediatric obesity.
Beyond sleep duration, other aspects of sleep such as timing and variability may be associated with obesity risk in youth. However, data regarding the same are limited. Marian Tanofsky-Kraff, National Institutes of Health, Bethesda, Maryland, USA, and colleagues tested whether multiple facets of sleep were associated with fat mass gain over 1 year using a longitudinal design.
For the study, a convenience sample of non-treatment-seeking youth (age 8-17 years) was made to wear actigraphy monitors for 14 days. The researchers calculated average weekly sleep duration, within-person sleep duration variability, weekend catch-up sleep, bedtime and wake time shift, social jet lag, bedtime, wake time, and sleep midpoint
A convenience sample of non-treatment-seeking youth (age 8-17 years) wore actigraphy monitors for 14 days. Average weekly sleep duration, within-person sleep duration variability, weekend catch-up sleep, bedtime and wake time shift, social jet lag, bedtime, wake time, and sleep midpoint were calculated. The association of each facet of baseline sleep with 1-year fat mass, adjusting for baseline fat mass and height, was examined.
A total of 137 youths (54.0% female; mean [SD], age 12.5 years; 28.4% non-Hispanic Black or African American; baseline fat mass = 15.3 kg; 1-year fat mass = 17.0 kg; 28.5% with baseline overweight or obesity) were studied.
Key findings of the study include:
Wake time and sleep midpoint were inversely associated with 1-year fat mass, such that earlier wake time and midpoint were associated with higher 1-year fat mass.
No other facet of sleep was significantly associated with 1-year fat mass.
"Using objective measures, youth with earlier wake times and sleep midpoints had greater gains in fat mass," the authors wrote. "Additional research is needed to determine whether sleep timing may be a modifiable target to prevent pediatric obesity."
Reference:
The study titled, "Longitudinal associations between facets of sleep and adiposity in youth," is published in the journal Diabetes.
DOI: https://onlinelibrary.wiley.com/doi/full/10.1002/oby.23281