Scroll Top

Sleep and Obesity

Woman Sleeping in Bed

Short sleep duration as a possible cause of obesity has received considerable attention in the media and scientific literature. Epidemiologic studies have consistently shown that short sleep and obesity are associated. Recent intervention studies have also shown that sleep restriction leads to weight gain in humans.  Other authors also reported that short sleep duration activates obesity-related genes, whereas longer sleep duration may be protective by suppressing genetic influences on body weight.

Previous research has been instrumental in showing that increased food intake is the main mechanism by which short sleep duration leads to weight gain. More recently, studies have provided important information to the effect that the hormonal explanation (e.g., changes in leptin and ghrelin concentrations) is probably not the most important mechanism to explain the link between reduced sleep and increased food intake. Indeed, in real-life conditions with free access to food, excess energy intake associated with sleep curtailment appears to be preferentially driven by hedonic rather than hormonal factors. Although food intake may be directly proportional to the time spent awake in the current obesogenic environment, studies consistently show that shortened sleep increases snacking, the number of meals eaten per day, and the preference for energy-dense foods. Interestingly, new neuroimaging experiments show that sleep restriction enhances hedonic stimulus processing in the brain underlying the drive to consume foods.

The growing body of evidence in this field of research reminds us that sleep is not a ‘‘waste of time’’ after all and the maintenance of healthy eating behaviors is compromised by not getting adequate sleep. Many people living in modern societies are sleep-deprived, and they generally underestimate the fact that sleep is as important as healthy eating and physical activity for good health. This observation is perhaps a wake-up call to better integrate our approaches to maximize success in our interventions aimed at managing weight problems and improving health outcomes.

Bottom Line: The longer you’re awake the more time you have to snack and the more you’ll crave sweet foods. Do everything you can to get 7 – 9 hours of sleep a night.

Here are some tips on How to Sleep Better.


  1. Chaput JP. Sleeping more to improve appetite and body weight control: dream or reality? Am J Clin Nutr. 2015 Jan;101(1):5-6. doi: 10.3945/ajcn.114.101543. Epub 2014 Dec 3. No abstract available.