Not only has recent research shown that poor sleep causes weight gain, but the reverse also appears to be true—dropping extra pounds enhances the quality of sleep among people who are overweight or obese, according to a new study by researchers Johns Hopkins University in Baltimore.
“We found that improvement in sleep quality was significantly associated with overall weight loss, especially belly fat,” says Dr. Kerry Stewart, professor of medicine at the Johns Hopkins School of Medicine and senior author of the study, which was presented at the American Heart Association Scientific Sessions in November.
For the six-month study, researchers followed 55 overweight volunteers who had Type 2 diabetes or prediabetes. Participants were divided into two groups—one went on a diet and had supervised exercise training, while the other only dieted.
Members of both groups lost an average of about 15 pounds and about 15% of belly fat.
Although a variety of sleep problems were reported by participants, none stood out as being most common, so the researchers analyzed a composite score that reflects overall sleep health and found both groups improved their overall sleep score by about 20%.
“The key ingredient for improved sleep quality from our study was a reduction in overall body fat, and, in particular, belly fat, which was true no matter the age or gender of the participants or whether the weight loss came from diet alone or diet plus exercise,” Stewart says.
