If You're Trying to Watch Your Weight: Sleep

A new study from France has found that people who are sleep deprived, even for as little as one night, eat significantly more the next day, compared to people who are well-rested. The study is published in the March 31st online issue of the American Journal of Clinical Nutrition.

Earlier studies have suggested that there may be a link between sleep and weight (i.e., less sleep may be connected to higher body mass indices (BMI) in general). But this is the first study to put that idea to the test over just a couple of nights.

But it’s just not that they ate a little more when they were sleep deprived – they ate 560 calories more, which is the equivalent of almost a full meal for most people.

Laurent Brondel of the European Center for Taste Sciences in Dijon, France, studied 12 healthy, normal weight men whose average age was 22. On the first day of the study, the men slept from 12 a.m. to 8 a.m. (this was the well-rested condition) and on the second day they slept from 2 a.m. to 6 a.m. (the sleep-deprived condition). They were able to eat as much as they liked throughout the study.

After getting only four hours’ worth of sleep in the sleep-deprived condition, the men consumed 22% more calories than they had when they were well-rested on eight hours of sleep. But it’s just not that they ate a little more when they were sleep deprived – they ate 560 calories more, which is the equivalent of almost a full meal for most people.

Why might this be the case? Earlier work has suggested that sleep deprivation disrupts normal levels of the hunger and satiation hormones, ghrelin and leptin. While this study didn’t measure hormone levels in the men, the participants did report feeling much hungrier after the night of sleep deprivation, suggesting that something may be occurring at the molecular level which should be teased apart further in future studies.

The authors conclude by saying that “sleep restriction could be one of the environmental factors that contribute to the obesity epidemic.” Whether one is trying to lose weight or just maintain a healthy weight, it is clear that getting enough sleep is an important ingredient.