Editors' ChoiceObesity

Paying Our Sleep Debt in Extra Pounds

See allHide authors and affiliations

Science Translational Medicine  27 Mar 2013:
Vol. 5, Issue 178, pp. 178ec51
DOI: 10.1126/scitranslmed.3006149

Sleep is vital to sustain life and well-being, but the long lines at coffee shops suggest that many people don’t sleep enough. According to the National Sleep Foundation, on average adults need between 7 and 9 hours of sleep per night, but less than half of us report sleeping this amount during the work week. So what price do we pay for our national sleep debt? Increased risks for diabetes, hypertension, and obesity are all medical conditions associated with decreased sleep, yet the mechanisms for these associations are not well defined.

To elucidate mechanisms by which insufficient sleep may contribute to weight gain and obesity, Markwald and colleagues examined the costs of limited sleep with regard to both energy expenditure (assessed by whole-room calorimetry) and energy consumption (assessed by measuring ad libitum food consumption). During the sleep-deprived condition, healthy, lean, adult volunteers were limited to just 5 hours of sleep per night for 5 nights, in essence mimicking a work week, whereas during the sleep-sufficient condition these participants were allowed to sleep for 9 hours per night for 5 nights. On average, the sleep-deprived condition resulted in an increase in energy expenditure (~5%) and an increase in food intake that exceeded the amount of energy expended, resulting in weight gain of about 0.82 kg (1.8 lbs). Additionally, with the sleep-deprived condition, participants consumed more carbohydrates overall, especially after dinner. Nighttime snacking nearly doubled (an increase of 42%), including carbohydrate-, protein-, and fiber-containing foods.

The authors conclude that we may consume more energy (eat more) to compensate for the increased energy that we expend during our additional waking hours. This seems a sensible physiologic response, but the problem is when we are faced with an environment of readily available, highly palatable foods. We overcompensate and eat more food than we actually need, with resulting weight gain. Perhaps we should advise our patients not only to eat less and move more, but also to sleep more rather than pay the cost in extra pounds.

R. Markwald et al., Impact of insufficient sleep on total daily energy expenditure, food intake, and weight gain. Proc. Natl. Acad. Sci. U.S.A., published online 11 March 2013 (10.1073/pnas.1216951110). [Abstract]

Navigate This Article