Modest sleep loss linked to weight gain in Columbia trial
Adults who slept about 80 minutes less a night for six weeks gained about a pound and became more sedentary, Columbia researchers reported.
By Lucas Ferreira · Science & Environment Writer
3 min read
Adults who cut their sleep by about 80 minutes a night for six weeks gained weight and spent more time sitting, according to researchers at Columbia University Vagelos College of Physicians and Surgeons. The finding adds evidence that routine short sleep may contribute to obesity-related health risks, including diabetes and heart disease, Columbia University Irving Medical Center reported.
The study followed 95 adults who usually slept seven to eight hours a night. In one six-week phase, participants pushed their usual bedtime later by 90 minutes; in another six-week phase, they kept their normal sleep schedule, according to Columbia.
Participants wore wrist monitors that recorded sleep and activity during both phases. Researchers also tracked body weight, waist size, body composition and fasting levels of hormones tied to appetite regulation, Columbia said.
During the shortened-sleep phase, participants gained an average of about one pound, according to the researchers. They also spent an average of 17 additional minutes per day sedentary. Among men and postmenopausal women, sedentary time rose by nearly 30 minutes a day, Columbia reported.
Faris Zuraikat, first author of the study and an assistant professor of nutritional medicine at Columbia, said the weight change was measured over a short period and could become more meaningful if similar sleep loss continued over a year. He also said the increase in inactivity remained apparent even after accounting for the fact that participants were awake longer.
Marie-Pierre St-Onge, the study leader and a professor of nutritional medicine at Columbia, said the results suggest adequate sleep may help lower the risk of weight gain and conditions linked to obesity. She said advice focused only on diet and exercise may be too narrow because maintaining those changes can be hard for many adults.
The Columbia team said much previous research on sleep and weight has examined more extreme sleep deprivation, including experiments that limited people to about four hours of sleep. Those studies have tied severe sleep loss to increased appetite and overeating, but Columbia said such conditions are difficult to sustain for more than a few days and may not reflect common sleep habits.
The new work was designed to test milder, longer-running sleep restriction closer to what many adults report. Columbia said about 30% of adults experience chronic mild sleep loss, including nights of five or six hours of sleep.
Columbia said the same participant group has been assessed in related research. In one earlier study, women with higher cardiometabolic risk who reduced sleep by about 80 minutes a night for six weeks developed greater insulin resistance, with the strongest effect among postmenopausal women. Another study found that men and women at elevated risk for heart disease had an increase in inflammatory cells in the heart after mild sleep restriction.
St-Onge said more research is needed to determine how sleep restriction contributes to weight gain and to test the health effects of improving sleep among people who regularly get too little.
The paper, listed in Annals of Internal Medicine as “Prolonged Short Sleep and Its Effect on Body Weight and Composition,” was published July 6, according to the journal reference cited by Columbia. The authors reported no conflicts of interest, and the research was supported by the American Heart Association and the National Institutes of Health.
This story draws on original reporting from ScienceDaily.