A new study from Columbia University reveals that losing just 80 minutes of sleep per night can lead to an average weight gain of one pound every six weeks. The research, published in the Annals of Internal Medicine, also found that participants became more sedentary, spending an average of 17 extra minutes per day sitting.
Study Details and Methodology
The study recruited 95 adults who typically slept seven to eight hours per night. Participants were instructed to delay their bedtime by 90 minutes for a six-week period, followed by six weeks of their usual sleep schedule. Wrist monitors tracked sleep, while researchers measured body weight, waist circumference, body composition, and fasting levels of appetite-regulating hormones.
Lead author Faris Zuraikat, assistant professor of nutritional medicine at Columbia, noted: “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. 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.”
Impact on Sedentary Behavior and Health Risks
Sedentary time increased by an average of 17 minutes per day during the sleep-restricted period, and by nearly 30 minutes per day for men and postmenopausal women. “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 said. “This is notable, as people who are more sedentary have elevated risk for chronic diseases.”
Previous studies on the same participants found that women with increased cardiometabolic risk who shortened their sleep by around 80 minutes per night over six weeks had increased insulin resistance, a risk factor for type 2 diabetes. The effects were more pronounced in postmenopausal women. Another study found that men and women with elevated heart risk had an influx of inflammatory cells in the heart after losing sleep.
Expert Commentary
Study leader Marie-Pierre St-Onge, professor of nutritional medicine in Columbia’s department of medicine and institute for human nutrition, said: “Our study shows that getting adequate sleep may help reduce the risk of weight gain and obesity-related conditions like heart disease and diabetes. People tend to gain weight over the course of their adulthood, and obesity is a major risk factor for heart disease.”
She added: “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. Now we need to understand the health effects of improving sleep in those who fail to get adequate sleep on a regular basis.”
The study was published in the Annals of Internal Medicine.
