MONDAY, June 8, 2009 (HealthDay News) -- Not getting enough sleep can make you start packing on the pounds almost immediately, a new study has found.
In the study, researchers put 92 healthy men and women aged 22 to 45 through an 11-day, controlled sleep-restriction experiment in a laboratory.
During the first two nights, study participants spent 10 hours a night in bed, followed by five nights of sleep restriction, and finally, four nights of varying recovery. Nine well-rested participants served as controls.
The sleep-deprived participants gained an average 1.31 kilograms (2.9 pounds) by the end of the study period. The well-rested controls gained none, according to the study to be presented Monday at the Associated Professional Sleep Societies annual meeting, in Seattle.
Participants were given three regular meals per day and access to healthy snacks. On the sleep-restriction nights, a small sandwich was provided at 1 a.m., the study authors noted.
Despite gaining weight, the sleep-deprived participants reported that their appetites had decreased, that they had fewer food cravings and that they had eaten less food, the researchers found. This contradicts previous research that has suggested lack of sleep may fuel cravings for the quick energy of carbohydrates.
Even though this study found the opposite -- lack of sleep didn't increase the desire to eat -- other factors may explain the weight gain, the researchers said. The sedentary environment of the laboratory and the opportunity to snack for longer periods due to reduction in time spent asleep might have encouraged noshing.
"During real-world periods of sleep restriction [say during shift work], people should plan their calorie intake over the time they will be awake, eating small, healthy meals," Siobhan Banks, a research fellow at the University of South Australia, said in a news release from the American Academy of Sleep Medicine.
To ward off weight gain, it's also a good idea to keep low-fat, low-sugar snacks on hand to reduce the temptation to eat high-fat, high-calorie comfort foods, and to maintain a regular exercise routine, Banks added.
"Even though people may feel tried, exercising will help regulate energy intake balance," Banks explained.
More information
The American Academy of Sleep Medicine has sleep tips for shift workers.
