MORNINGSIDE HEIGHTS, N.Y., July 28 (Our New York News) — For people who routinely cut sleep short, the effect may show up first as a small bump on the scale and a little less movement during the day. Columbia University researchers in New York found that adults who slept about 80 to 90 minutes less per night for six weeks gained about 1 pound on average and became more sedentary.
What the study looked at
The study, published in Annals of Internal Medicine, followed 95 adults who were already at increased risk for heart or metabolic disease. Researchers compared a six-week period of adequate sleep with a six-week period of sleep restriction.
During the sleep-loss phase, participants also showed a modest increase in waist size, about 0.52 centimeters on average, or roughly half a centimeter, according to the study results reported by Columbia University.
What that means for everyday life
The finding is not a warning that one short night will cause major weight gain. Instead, it points to what can happen when short sleep becomes a pattern.
Columbia said participants spent more time being sedentary when they slept less, averaging 17 extra sedentary minutes per day overall. Among men and postmenopausal women, sedentary time rose by nearly 30 minutes per day.
Faris Zuraikat, an assistant professor of nutritional medicine at Columbia, said the change was small over six weeks but could add up over time. “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,” he said in Columbia’s release. He added that when the results are extended over a full year, losing less than an hour and a half of sleep per night could lead to clinically meaningful weight gain.
Why sleep matters here
The Columbia release said the study was designed to mimic sleep patterns that many adults experience chronically. That makes the result relevant to a common habit: shaving time off sleep to make room for work, family, screens, or other demands.
The practical takeaway is that sleep is not only about feeling rested the next day. In this study, repeated short sleep was linked to slightly higher body weight, a small increase in waist size, and more time spent sitting.
What the study does not show
The research does not prove that every person who sleeps less will gain weight at the same rate. It also studied a specific group of adults at higher health risk, so the results may not look exactly the same for everyone.
Still, the study adds to evidence that sleep habits can affect more than mood and alertness. For people trying to manage weight, the Columbia findings suggest that protecting sleep may be part of the picture, not just an afterthought.
