Sleep Loss Favors Weight Gain

Researchers measured biochemical, physiological, and behavioral responses to food after depriving participants of sleep. The results they found were sobering.

Much to the irritation of my wife, I like to keep to a regular sleep schedule. I’m asleep before 11 PM every night and up at 6 AM every morning. Even on the weekends, I still end up sleeping around this same time. Thankfully, I’ve got expert opinion backing me up on the importance of a regular sleep schedule.

According to a new study from the Uppsala University in Sweden, a lack of sleep can have a direct influence on your waistline. Insufficient sleep can lead to adverse metabolic effects, including obesity.

The Swedish researchers conducted multiple human studies into the consequences of sleep loss on energy metabolism. They measured biochemical, physiological, and behavioral responses to food after depriving participants of sleep. The results they found were chilling.

People suffering from sleep loss tend to consume more calories, experience more pleasure from food, prefer larger portions, and tend to be more impulsive with their eating and food choices. Not only that, but they expend less energy during the day.

Sleep loss changes the hormonal balance, decreasing the production of satiety hormones (leptin or GLP-1) and increasing hunger hormone production (ghrelin). Sleep loss also raises endocannabinoid levels, which can stimulate an increase in appetite. The gut bacteria are also affected by a lack of sleep, leading to a decrease in metabolic efficiency. Finally, the body is less sensitive to insulin when it’s running on less than a full night of sleep.

Sleep schedules are necessary because of the circadian rhythm, the 24-hour cycle of sleep and wakefulness that is affected by sunlight, exercise, food, temperature, and sleep patterns, among other things. With a regular sleep schedule, your body acclimates to getting a certain number of hours of rest per night. You can essentially train your body to sleep anywhere from 5 to 8 hours a night just by going to bed and getting up at the same time.

The author of the study, Dr Christian Benedict from Uppsala University, Sweden, remarks, “Since perturbed sleep is such a common feature of modern life, these studies show it is no surprise that metabolic disorders, such as obesity are also on the rise.”

Although Dr Benedict’s work has shed light on how short periods of sleep loss can affect energy metabolism, longer-term studies are needed to validate these findings. The group are now investigating longer-term effects and also whether extending sleep in habitual short sleepers can restore these alterations in appetite and energy metabolism.

Dr Benedict adds, “My studies suggest that sleep loss favors weight gain in humans. It may also be concluded that improving sleep could be a promising lifestyle intervention to reduce the risk of future weight gain.”


1. Benedict, Christian. “Candidate Mechanisms Underlying the Association between Poor Sleep and Obesity,” May 3, 2017. doi:10.1530/endoabs.49.S28.1.