Teens who skimp on sleep could be setting themselves up for obesity just a few years later, a new study suggests.
Researchers from Columbia University and the University of North Carolina found an association between getting fewer than six hours of shut-eye a night at age 16 and having a 20 percent higher risk of obesity by age 21, compared with 16-year-olds who slept more than eight hours a night.
Teens typically need around nine-and-one-quarter hours of sleep a night, according to the National Sleep Foundation.
For the study, published in the Journal of Pediatrics, researchers examined health information from 10,000 U.S. 16- and 21-year-olds who were part of the National Longitudinal Study of Adolescent Health. Researchers collected information on their height and weight in 1995, and then again in 2001.
When the study participants were 16, nearly one-fifth of them got less than six hours of sleep a night. Researchers found that these participants -- both male and female -- had an increased risk of obesity at age 21. "Optimizing sleep duration during adolescence may be an important modifiable intervention for obesity prevalence in older adolescents and young adults," the researchers wrote in the study.
While the study didn't examine reasons for the association, sleep deprivation has been shown in past research to affect the health of teens in a number of ways. A study presented at the SLEEP 2013 conference showed that sleep-deprived teens tend to gravitate toward more unhealthy food than well-rested teens. And a study published this year in the Journal of Pediatrics showed that for obese teens, sleep seems to be associated with cardiometabolic risk (which includes things like high blood pressure, blood sugar and body mass index). Another study published this year in the journal Preventive Medicine also showed that sleep-deprived teens are more likely to engage in a whole host of risky behaviors.