At a Glance
- In a randomized clinical trial, overweight adults who increased how much they slept took in fewer calories.
- The results suggest that improving sleep duration can help boost the success of weight-loss interventions
Sleep is as important for good health as diet and exercise. Guidelines recommend that adults get a minimum of 7 hours of sleep a night. Children and teens need even more. But sleep deprivation, whether temporary or chronic, is common in the U.S. About a third of American adults report not getting enough sleep.
Not getting enough quality sleep raises the risk of many diseases and disorders. And a chronic lack of sleep has been identified as a risk factor for obesity. Laboratory studies have shown that sleep restriction stimulates appetite and increases cravings for high-calorie food. However, the reverse—whether increasing the amount of sleep people get in their daily lives can help reduce calorie intake—hasn’t been clear.
To answer this question, researchers led by Dr. Esra Tasali from the University of Chicago enrolled 80 adults into a randomized clinical trial of sleep extension in real-world settings. All study participants were overweight and between the ages of 21 and 40. They regularly got an average of less than 6 and a half hours of sleep per night due to habits or lifestyle, not medical reasons.
During the study, participants’ sleep habits were monitored at home using motion trackers worn on the body. Energy expenditure was tracked by having them drink water with tracers that could be measured in urine over the course of the trial. The researchers also monitored participants’ body weight and composition during the study.
During the first two weeks of the trial, participants continued their regular sleep patterns. On day 15, they were randomly assigned to either receive sleep extension counseling or continue their sleep habits (the control group). The sleep extension group received a session of personalized counseling on good sleep hygiene, such as setting regular bed and wake times and limiting screen use before bed. They also received one follow-up session a week later.
The researchers calculated changes in calorie intake during the two-week intervention using the energy expenditure, weight, and body composition data. The trial was funded in part by NIH’s National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and National Center for Advancing Translational Sciences (NCATS). Results were published on February 7, 2022, in JAMA Internal Medicine.
Participants in the sleep extension group increased the amount of sleep they got by an average of 1.2 hours. They also took in an average of 270 calories a day less than the control group. If healthy sleep habits were maintained over longer periods, a deficit of 270 calories a day would lead to clinically important weight loss over time.
“We’ve shown that in real life, without making any other lifestyle changes, you can extend your sleep and eat fewer calories,” Tasali says. “This could really help people trying to lose weight.”
The study suggests that healthy sleep behavior could be a new tool to help tackle the epidemic of obesity. However, more work is needed to know whether improved sleep duration could help with obesity prevention and weight loss over a longer period of time.