A recent study published in the American Journal of Clinical Nutrition suggests that “sleep restriction could be one of the environmental factors that contribute to the obesity epidemic.”* In particular, the study discovered that normal-weight young men ate several hundred extra calories a day when they’d gotten just four hours of sleep compared to when they slept for a full eight hours.
The study, led by Dr. Laurent Brondel of the European Centre for Taste Sciences in Dijon, France, followed the sleep, eating, and energy expenditure in 12 healthy young men across two 48-hour periods. Two days served as a control period, where the men in the study adhered to their normal routines but wrote down their sleep, eating, and activities in a diary. During the second 48-hour period, the men went to bed at 12 am and woke up at 8 am on one day, and on the other day they went to bed at 2 am and woke up at 6 am. There were no eating restrictions during each period.
Researchers found that after the short night sleep, the men consumed 22% more calories, on average, than when they were allowed to sleep eight hours. This accounted for nearly 560 extra calories a day per person.
Editor’s note: Getting adequate sleep may be beneficial when trying to follow a low-calorie or calorie restricted diet.