Cutting back on sleep, even for a short period, can lead to weight gain, according to a new study. Experts advise that sleep is as important as diet and exercise for weight management, and that chronic sleep deprivation should be viewed as a warning sign of health problems.
Cutting 90 Minutes of Sleep for Six Weeks Increased Both Weight and Waist Size
According to a recent report by the New York Post, a study published in the medical journal Annals of Internal Medicine found that adults who reduced their nightly sleep by about 90 minutes gained an average of roughly 0.45 kilograms over six weeks.
Researchers at Columbia University Irving Medical Center in the United States compared two lifestyle patterns among 95 adults at risk of cardiovascular or metabolic disease. Participants slept normally with sufficient sleep during one period, and during another period reduced their sleep by about 90 minutes each day, continuing this for six weeks.
As a result, participants' average weight increased by about 0.45 kilograms at the end of the sleep-restricted period, and their waist circumference also grew slightly.
Interestingly, no statistically significant changes appeared in body fat or muscle mass. The researchers explained that while weight increased first, an increase in body fat could only be confirmed after a longer period.
Changes also appeared in participants' lifestyle. During the sleep-deprived period, time spent sitting increased, but there was little difference in the time spent on moderate or higher physical activity such as walking or exercise.
"Sleep Is a Weight-Control Switch"...Menopausal Women More Vulnerable
Dr. Somi Javaid, an obstetrician-gynecologist in Ohio in the United States who did not participate in the study, explained that sleep is a key factor governing metabolism and weight control.
She said chronic sleep deprivation can reduce the body's ability to control weight, and that women going through menopause in particular may face an even greater risk of weight gain as hormonal changes and sleep disorders overlap.
"Women are experiencing a collapse in sleep quality at a time when their metabolism is most sensitive, yet we are telling them to eat less and just exercise more," Dr. Javaid said, raising questions about current approaches to weight management.
She also noted that the American Heart Association (AHA) includes sleep in "Life's Essential 8," its core set of metrics for assessing cardiovascular health.
The American Heart Association recommends 7 to 9 hours of sleep per day for adults.
"Sleep Deprivation Is Not a Lifestyle Habit but a Health Problem"
The researchers explained that several limitations should be considered when interpreting the results.
First, the study period was only six weeks, making it difficult to fully confirm changes that appear over longer periods, such as body fat, and the number of participants, at 95, was not large. Because food intake was not measured, it is also difficult to pinpoint the direct cause of the weight gain.
Nevertheless, experts assessed that the study once again demonstrates the link between sleep deprivation and weight gain.
"Chronic sleep deprivation is not simply a lifestyle habit but an important signal showing one's health condition," Dr. Javaid stressed. "For weight management or cardiovascular health, sufficient sleep must be managed together with diet and exercise."
