Mild Sleep Deprivation Leads to Measurable Weight Gain, Columbia Study Finds
核心洞察
A six-week study found that reducing sleep by approximately 80 minutes per night led to an average weight gain of about 0.45 kg (one pound) in adults.
Participants also increased sedentary time by an average of 17 minutes per day, with men and postmenopausal women increasing by nearly 30 minutes.
The findings challenge the notion that only severe sleep deprivation affects weight, showing that mild, chronic sleep loss—affecting roughly 30% of adults—has measurable metabolic consequences.
Researchers at Columbia University's Vagelos College of Physicians and Surgeons have demonstrated that chronic, mild sleep deprivation—a pattern affecting roughly 30% of adults—can lead to measurable weight gain over a relatively short period. The study, which tracked 95 adults who typically slept seven to eight hours per night, found that delaying bedtime by 90 minutes for six weeks resulted in an average weight increase of approximately 0.45 kilogram, or about one pound.
"Our study shows that getting adequate sleep may help reduce the risk of weight gain and obesity (搜索)-related conditions like heart disease (搜索) and diabetes," said Marie-Pierre St-Onge, 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 healthier diet and getting more physical activity to offset weight gain is simplistic and can be difficult to maintain."
Bridging a Gap in Sleep Research
Much of the existing research on sleep deprivation and obesity (搜索) has focused on severe sleep restriction, typically limiting participants to about four hours of sleep opportunity. Those studies have shown that extreme sleep loss leads to changes in appetite and overeating, which can contribute to weight gain over time. However, most people cannot tolerate such severe deprivation for more than a few days, limiting the practical utility of those findings.
"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 noted.
The Columbia team designed their study to mimic the sleep patterns that many adults experience chronically. Participants were instructed to delay their normal bedtime by 90 minutes for one six-week phase and to maintain their usual sleep schedule for another six-week phase. Sleep duration and physical activity were measured throughout each phase using wrist-worn monitors, alongside changes in body weight, waist circumference, body composition, and fasting levels of several appetite-regulating hormones.
Sedentary Behavior Increases Alongside Weight
Beyond the weight gain, researchers observed a notable increase in sedentary time. During the sleep-restricted phase, the average amount of time participants spent sitting increased by 17 minutes per day. When the analysis was limited to men and postmenopausal women, sedentary time increased by nearly 30 minutes per day.
"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," said Faris Zuraikat, assistant professor of nutritional medicine at Columbia and first author of the study. "This is notable, as people who are more sedentary have elevated risk for chronic diseases."
Hormonal Findings Challenge Prior Theories
Interestingly, the study found that levels of leptin—a hormone that suppresses appetite—were actually higher during the period of sleep restriction. This finding runs counter to theories advanced by studies on severe sleep restriction, which have suggested that hormonal disruptions drive overeating. At least as far as leptin is concerned, that mechanism does not appear to apply in the context of mild, chronic sleep deprivation.
Broader Metabolic and Cardiovascular Implications
The weight gain findings build on previous research from St-Onge's team involving subsets of the same participant group. In one related study, women at high risk for cardiovascular and metabolic diseases who shortened their sleep by approximately 80 minutes per night over six weeks showed increased insulin resistance, a risk factor for type 2 diabetes (搜索). This effect was particularly pronounced in postmenopausal women.
Another study from the same cohort demonstrated that mild sleep reduction in men and women at elevated heart risk caused immune cells in the blood to become more likely to migrate to sites of inflammation.
"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 (搜索)-related conditions like type 2 diabetes (搜索) and heart disease (搜索)," St-Onge said.
Clinical Significance Over Time
While a one-pound gain over six weeks may appear modest, Zuraikat emphasized the cumulative implications: "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."
The research team's next focus will be understanding the health effects of improving sleep duration in those who chronically fail to get adequate rest. "Now we need to understand the health effects of improving sleep in those who fail to get adequate sleep on a regular basis," St-Onge said.