Losing weight, and more specifically belly fat, can improve the quality of sleep for people who are obese or overweight. A recent study found that weight loss due to diet and a combination of diet and exercise effectively improves sleep. Researchers looked at two groups of overweight or obese participants with diabetes or pre-diabetes. One group only dieted; the other group dieted and exercised. Both lost  an average of 15 pounds and 15 percent belly fat per person and also experienced improved quality of sleep.

Source:
Medical News Today