The Scary Link Between Losing an Hour of Sleep and Packing on Weight Gain
By now, we all know that failing to get enough sleep on any given night is never a good thing. Aside from leaving you groggy and brain dead the following day, consistently getting poor sleep has been linked to serious long-term health consequences, including a higher risk of dementia and heart disease.
Now, as a recent study published in Annals of Internal Medicine suggests, sleep deprivation may not be so good for your waistline either. Researchers found that adults who consistently slept about 90 minutes less per night for six weeks gained weight, increased waist circumference, and became more sedentary compared to when they got adequate sleep.
The study pooled data from 95 adults at an elevated cardiometabolic risk. Prior to the study, all participants regularly slept at least seven hours per night. Each participant completed two six-week study periods. During one period, they maintained their normal sleep schedule. During the other, their bedtime was delayed by 90 minutes each night. Researchers measured body weight, waist circumference, body composition, and energy balance behaviors and biomarkers over these periods.
After six weeks of sleep restriction, participants weighed an average of almost one pound more than they did during the adequate sleep phase. Their waist circumference also increased by an average of 0.52 centimeters, and overall body volume was slightly higher. Researchers also found that participants spent an additional 17 minutes per day being sedentary during the sleep restriction phase. Leptin levels, a hormone involved in regulating energy balance and appetite, were also elevated.
While the average weight gain over six weeks of this study period was modest, researchers concluded that prolonged exposure to moderately short sleep may lead to weight gain. Accordingly, they suggest that weight management and cardiometabolic disease prevention programs should consider incorporating sleep strategies that help individuals consistently get adequate sleep.
The study's findings only add to the growing evidence that sleep is just as important to long-term health implications as diet and exercise. One previous study found that better sleep quality and quantity increased the likelihood of successful weight loss by 33 percent. Another meta-analysis linked insomnia to a 45 percent higher risk of developing or dying from cardiovascular disease.
Most experts recommend aiming for at least seven hours of sleep each night while keeping a consistent bedtime and wake-up time, even on weekends. If you struggle to get to sleep, experts also recommend reserving your bed as a place your body associates with sleep over stress.
"For people dealing with insomnia, it's easy to get into the habit of lying awake in bed for long stretches, checking the clock, getting frustrated, and basically training the brain that bed is where you struggle to sleep," says Drew Miller, Vice President of Marketing at Sit 'n Sleep . "If you're awake and restless, it can help to get up, do something quiet and low-stimulation in dim light, and come back to bed when you feel sleepy again. Over time, that consistency can help rebuild the connection between bed and rest."
Related: The Unexpected Trick Olympians Use to Instantly Upgrade Their Sleep Quality While Traveling
This story was originally published by Men's Journal on Jul 9, 2026, where it first appeared in the Health section. Add Men's Journal as a Preferred Source by clicking here.
