Obese adults sleep less than others, study finds

Sept. 14 (UPI) -- Obese adults get about 15 minutes less sleep per night than those who maintain a healthy weight or are merely overweight, a study published Monday by JAMA Internal Medicine found.

Those defined as excessively overweight slept about six hours, 36 minutes per night over more than a two-year period, the data showed.

Meanwhile, adults who were just overweight or who maintained a healthy weight got about six hours, 52 minutes of sleep per night over the same period, the researchers said.

"Shorter sleep duration and greater sleep variability were both associated with higher BMI," wrote the authors, from the Scripps Research Translational Institute in San Diego.

The findings are based on an analysis of sleep and body weight trends among U.S. adults based on body mass index.

BMI is calculated by taking people's weight in kilograms and dividing it by the square of their height in meters. It is a commonly used measure for assessing whether someone is overweight or obese.

A person with a BMI between 25 and 30 is considered overweight, while someone with a BMI above 30 is defined as obese, or excessively overweight, based on guidelines from the Centers for Disease Control and Prevention.

The agency recommends that adults get an average of seven hours of sleep during a 24-hour period.

For this study, the Scripps scientists analyzed sleep data on more than 120,000 American adults, based on Fitbit readings collected between March 2016 and May 2018.

Overall, the adults included in the study slept an average of about six hours, 47 minutes per night, the researchers said.

However, 46% of those with BMIs above 30 reported "sleep variability" -- meaning that the amount they slept varied nightly -- while 38% of those with BMIs below 30 reported sleep variability, the data showed.

"While we cannot determine the direction of association from our study result, these findings provide further support to the notion that sleep patterns are associated with weight management and overall health," the Scripps researchers wrote.