More Pillow Time, Less Weight Worries for Teens

Too little sleep for teens linked to unhealthy weight control behaviors like purging and fasting

/ Author:  / Reviewed by: Robert Carlson, M.D Beth Bolt, RPh

(RxWiki News) Teens may be famous for not getting all the sleep they need — or getting too much. Either way, getting sufficient sleep may be important for both their weight and mental health.

A recent study found that teens getting less sleep than needed each night were more likely to try to lose weight in unhealthy ways.

Fasting (not eating at all), purging (vomiting) and diet pills are all unhealthy ways to lose weight, and some diets can be unhealthy as well.

Yet these behaviors were more likely among boys getting only five hours or less of sleep each night and girls getting only 6 to 7 hours or less.

"Be sure your teen gets enough sleep each night."

The study, led by Anne G. Wheaton, PhD, of the National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, in Atlanta, Georgia, looked at whether teens' amount of sleep each night was related to their attempts to control their weight.

The researchers analyzed data from 12,087 students who responded to the National Youth Risk Survey. This survey asked about their typical number of hours of sleep each night and whether the students had done anything in an attempt to control their weight in the month before the survey.

An attempt to control their weight meant any activity, such as dieting or exercise, that they did to lose or maintain their weight.

The teens' answers on sleep were divided into four categories: very short sleep (5 hours or less), short sleep (6 to 7 hours), moderate (8 to 9 hours) or long (at least 10 hours).

The researchers adjusted their analysis to account for differences among the teens in terms of their race/ethnicity, grade level and body mass index (BMI).

BMI is a ratio of a person's weight to height that is often used to determine if that person has a healthy weight.

About half the teens reported that they slept for short durations — 52 percent of boys and 54 percent of girls.

About 15 percent of boys and 17 percent of girls reported getting very short sleep of five hours or less each night.

Boys who slept these very short periods were more likely than those sleeping a moderate amount to have dieted, fasted or purged (intentionally vomiting up food they have eaten) in an attempt to lose or maintain their weight.

About 36 percent of boys sleeping a very short amount had dieted, compared to 26 percent of boys getting a moderate amount of sleep.

Meanwhile, 14 percent of boys getting very short sleep had fasted, compared to only 4 percent of boys getting moderate sleep.

While 4 percent of boys getting very short sleep had purged, only 1 percent of boys getting moderate sleep had purged.

The rates among girls for dieting, fasting or taking diet pills were highest for very short sleepers, but they were also increased for short sleepers.

Well over half the girls getting very short sleep (60 percent) reported dieting, compared to 55 percent of girls getting short sleep and 48 percent of girls getting moderate sleep.

Over a quarter of girls getting very short sleep (28 percent) fasted to lose or maintain their weight, compared to 15 percent of girls getting short sleep and 10 percent of girls getting moderate sleep.

Among girls who had taken diet pills in the previous month, 13 percent were very short sleepers, 7 percent were short sleepers and 4 percent were moderate sleepers.

The rates of purging among girls were only significantly higher among the very short sleepers, with 12 percent reporting purging in the past month. Among short sleepers, that number was 6 percent, and among moderate sleepers, the number was 4 percent.

"Self-reported short sleep duration was associated with dieting and three unhealthy weight-control behaviors in this population," the researchers wrote. "If our findings are confirmed, intervention studies should be conducted to examine the effect of educational interventions."

This study's findings affirm what sleep doctors already understand about the importance of sleep, according to William Kohler, MD, the director of Pediatric Sleep Services at Florida Hospital Tampa.

"The bottom line is basically that sleep and metabolism are linked, and adequate sleep is important as far as ideal functioning," Dr. Kohler said. "Whether it be for cognition, weight control or behavior, the proper quality and quantity of sleep is very important."

He noted that there is already awareness of a link between poor sleep and weight management.

"It's interesting that previous studies have shown that lack of sleep, insomnia, can predict later development of obesity," Dr. Kohler said. "In this particular study, apparently teenagers attempted to improve their weight by various types of dieting and binging."

This study was published in the August issue of the journal Sleep.

The research was funded by the Centers for Disease Control and Prevention (CDC) and the Association for Prevention Teaching and Research. The authors reported no potential conflicts of interest.

Review Date: 
August 29, 2013
Last Updated:
December 30, 2013