Study Reveals Impact of Sleep Loss on Weight Gain

New Delhi, India Jul 13, 2026 ALN: Getting a little less sleep each night may have a bigger impact on your than you realize. Researchers at Columbia University Vagelos College of Physicians and Surgeons found that adults who cut their nightly sleep by about 80 minutes for six weeks gained an average of one pound and spent more time being inactive. This study highlights the often-overlooked relationship between sleep patterns and weight management, suggesting that even minor reductions in sleep can have significant repercussions.

The findings add to growing evidence that consistently getting enough sleep may play an important role in preventing weight gain and lowering the risk of obesity-related diseases. Obesity is a complex condition influenced by various factors, including diet, physical activity, genetics, and environmental influences. However, the role of sleep has gained increasing attention in recent years, as researchers seek to understand how lifestyle choices contribute to overall .

"Our study shows that getting adequate sleep may help reduce the risk of weight gain and obesity-related conditions like heart disease and diabetes," says Marie-Pierre St-Onge, a professor of nutritional medicine in Columbia's Department of Medicine and Institute for Human Nutrition and study leader. "People tend to gain weight over the course of their adulthood, and obesity is a major risk factor for heart disease. But focusing on eating a ier diet and getting more physical activity to offset weight gain is simplistic and can be difficult to maintain." This statement underscores the need for a holistic approach to , one that incorporates not just diet and exercise but also sleep hygiene as a critical component of weight management.

Looking Beyond Extreme Sleep Deprivation

Much of the previous research connecting poor sleep with obesity has focused on severe sleep deprivation, often limiting people to only four hours of sleep. Those studies have shown that extreme sleep loss can increase appetite and overeating, factors that contribute to weight gain. However, such severe sleep restriction is difficult for most people to tolerate for more than a few days. This raises questions about the applicability of these findings to the general population, where most individuals experience chronic, mild sleep deprivation rather than extreme cases.

"These studies only show us what happens under the most extreme conditions and don't tell us if mildly sleep-deprived people, like a lot of Americans who get 5 or 6 hours of sleep a night, will gain weight," St-Onge says. To better reflect real life, the researchers examined the effects of chronic, mild sleep loss, a pattern experienced by roughly 30% of adults. This demographic includes those who may not recognize their sleep patterns as problematic, often attributing fatigue to busy lifestyles or stress rather than inadequate rest.

Six Weeks of Less Sleep Led to Measurable Changes

The study included 95 adults who normally slept between 7 and 8 hours each night. During one six-week study period, participants delayed their usual bedtime by 90 minutes. During another six-week period, they followed their normal sleep schedule. This design allowed researchers to compare the effects of reduced sleep with a baseline of adequate sleep, providing a clearer picture of how even slight changes in sleep duration can affect weight and activity levels.

Throughout both phases, participants wore wrist monitors that tracked sleep and physical activity. Researchers also measured body weight, waist circumference, body composition, and fasting levels of several hormones involved in appetite regulation. These comprehensive measurements are crucial for understanding the multifaceted relationship between sleep and weight, as they account for various biological and behavioral factors that may influence outcomes.

"While the one-pound weight gain observed with modest sleep curtailment is not overwhelming, it is important to remember this is occurring over just six weeks," says Faris Zuraikat, assistant professor of nutritional medicine in Columbia's Department of Medicine and Institute for Human Nutrition and first author of the study. "Our study was designed to mimic sleep patterns that most adults experience chronically. When extrapolated to a full year, we would expect that losing less than an hour and a half of sleep per night could result in clinically meaningful weight gain." This projection highlights the potential long-term consequences of chronic sleep deprivation, which could lead to significant issues if not addressed.

Less Sleep Also Meant More Sitting

The researchers found that participants became less active during the sleep restriction phase. On average, sedentary time increased by 17 minutes per day. Among men and postmenopausal women, inactivity rose by nearly 30 minutes each day. This increase in sedentary behavior is particularly concerning, as it has been linked to a range of problems, including cardiovascular disease and type 2 diabetes. The study suggests that insufficient sleep not only contributes to weight gain but also fosters a lifestyle characterized by reduced physical activity.

"Even when we accounted for the fact that they were awake longer when sleep was shortened, participants spent more time being inactive than when they got adequate sleep," Zuraikat says. "This is notable, as people who are more sedentary have an elevated risk for chronic diseases." The implications of these findings extend beyond weight management, suggesting that sleep quality and quantity may also play a crucial role in overall physical fitness and .

Earlier Research Suggests Broader Effects

The same group of participants has also been examined in related studies. In one previous investigation, women with increased cardiometabolic risk who reduced their sleep by about 80 minutes each night for six weeks developed greater insulin resistance, an important risk factor for type 2 diabetes. The effect was especially pronounced in postmenopausal women, highlighting the need for targeted interventions to address sleep deprivation in vulnerable populations. Another study found that men and women with elevated heart disease risk developed an influx of inflammatory cells in the heart after experiencing mild sleep restriction, further solidifying the link between sleep and cardiovascular .

"Though more research is needed to further understand how sleep restriction leads to weight gain, all of our findings suggest that insufficient sleep increases the risk of obesity-related conditions like type 2 diabetes and heart disease," St-Onge says. This statement reinforces the idea that sleep is a critical component of that should not be overlooked in discussions about obesity and chronic disease prevention.

"Now we need to understand the effects of improving sleep in those who fail to get adequate sleep on a regular basis." This call for further research emphasizes the importance of developing effective strategies to enhance sleep quality and duration, particularly for those at risk of obesity and related issues. The study, titled "Skimping on Sleep and Its Impact on Body Weight and Composition: A Pooled Analysis of Randomized Trials," was published on July 6 in Annals of Internal Medicine. The authors report no conflicts of interest, and the research was supported by the American Heart Association and the National Institutes of .