For obese men, a dramatic weight loss can be an effective way to improve moderate to severe sleep apnea. Those with severe sleep apnea benefited most from weight loss.

"Our findings suggest that weight loss may be an effective treatment strategy for sleep apnea in obese men," says Kari Johansson, one of the researchers involved in the report from Karolinska Institute in Sweden.

Sleep apnea—the temporary cessation of breathing during sleep—is a relatively common but under-diagnosed disease. Five or more such events per hour is considered a disease. Untreated, sleep apnea is associated with an increased risk of traffic accidents, as well as stroke and heart disease. Moderate and severe sleep apnea also increases the risk of premature death. It has long been known that overweight or obese people are more likely to develop the disease, and that men are more affected than women.

In a randomized study published in the British Medical Journal, researchers at Karolinska Institute studied whether or not weight-loss can help to cure moderate and severe sleep apnea. The study included 63 obese men (BMI between 30 and 40) between the ages of 30 and 65. The participants had moderate to severe sleep apnea. All participants used CPAP— continuous positive airway pressure—treatment which produces more normal breathing patterns during sleep. The participants were randomly assigned to two groups. For nine weeks, one group underwent an intense weight-loss program while the other served as a control group.

The results of the study show that the weight loss group lost an average of 42 pounds and more than halved the number of apnea events.