MORNINGSIDE HEIGHTS, N.Y., July 28 (Our New York News) — For many people in New York City, the question is not whether sleep matters, but how much one short night adds up over time. A new Columbia University study suggests that skipping sleep regularly may nudge weight upward in a way that is easy to miss week by week.
Researchers at Columbia University Vagelos College of Physicians and Surgeons and Columbia University Irving Medical Center reported that adults who slept about 80 to 90 minutes less per night for six weeks gained about 1 pound on average. The study, published July 6 in Annals of Internal Medicine, also found that participants became more sedentary and had a slightly larger waistline.
What did the study measure?
The Columbia team studied 95 adults who were already at elevated risk for heart or metabolic disease. In the sleep-restriction phase, participants slept less each night for six weeks. In the comparison phase, they got adequate sleep.
According to the university’s news release, the sleep-restriction phase was linked with an average increase of 17 sedentary minutes per day. Among men and postmenopausal women, sedentary time rose by nearly 30 minutes per day.
The reported waist change was modest: about 0.52 centimeters, or roughly half a centimeter. Secondary coverage of the paper also said the study did not find significant changes in body fat or muscle mass.
How much should a reader worry?
The key point is scale. The weight gain reported in the Columbia study was small over six weeks, not a sudden or dramatic jump. Faris Zuraikat, the study’s first author, said in Columbia’s release that the one-pound gain was “not overwhelming,” but that it matters because it happened over only six weeks. He also said that, if the pattern were stretched across a full year, losing less than an hour and a half of sleep each night could lead to clinically meaningful weight gain.
That does not mean every short night will cause a pound to appear on the scale. But the study suggests that a pattern of short sleep can affect daily behavior in ways that matter, especially if it becomes chronic.
Why would less sleep affect weight?
The Columbia release says the study was designed to mimic sleep patterns many adults experience over time. The researchers found that people were more sedentary when they slept less. One likely reason, based on the paper as summarized in later coverage, is that less sleep can change how active people are during the day. The exact mechanism was not fully spelled out in the Columbia release.
What is the takeaway?
For most people, the study’s message is not to panic over one late night. It is that repeated sleep loss may make it easier to sit more and gradually gain weight, even when the increase is small at first.
In other words, sleep is not just about feeling rested the next day. According to Columbia’s researchers, it may also be part of the long-term picture for body weight and waist size.
