Getting just a bit less sleep than usual might be enough to cause weight gain, according to new research from Columbia University. While previous studies often looked at extreme sleep deprivation, this latest work suggests that chronic, mild sleep loss—like sleeping five to six hours a night—can have a real impact on your weight.
Dr. Marie-Pierre St-Onge, a professor at Columbia University's Vagelos School of Medicine, stated that adequate sleep could be key to reducing the risk of weight gain and associated health issues like heart disease and diabetes.
The study involved 95 adults who usually slept at least seven hours a night. For six weeks, they were asked to cut their sleep by about 90 minutes each night. Researchers tracked their sleep, physical activity, weight, waist size, body composition, and appetite-regulating hormones. For another six weeks, the participants returned to their normal sleep schedules.
Results showed that during the sleep-restricted period, participants gained an average of about a pound. Extrapolating this over a year suggests chronic mild sleep deprivation could lead to significant weight gain. Interestingly, during this time, participants also spent more time sitting, even after accounting for the extra waking hours.
While a hormone that typically suppresses appetite (leptin) was found to be higher during sleep restriction, challenging some previous theories about appetite hormones, the study also highlighted other health concerns. A previous look at a subset of these participants revealed that reduced sleep increased insulin resistance in women at high risk for cardiovascular and metabolic diseases. For both men and women at high risk for heart disease, mild sleep reduction also affected immune cells, making them more likely to move towards inflammation sites.
These findings suggest that even the everyday sleep deficits many people experience can measurably affect weight, activity levels, and appetite hormones. Dr. St-Onge emphasized that insufficient sleep increases the risk of obesity-related conditions and that the next step is to explore the benefits of improving sleep duration for those struggling with chronic sleep loss.
