According to new research people who snore burn more calories than those who sleep quietly. People who had severe sleep apnea burned 373 extra calories a day as compared to those who had mild sleep apnea though despite this the extra weight did not get offset.

Study author Dr. Eric J. Kezirian, director of the division of sleep surgery at the University of California, San Francisco said, "We want to figure out how to treat people with this disorder. Losing weight dramatically decreases obstructive sleep apnea in those who are overweight. But the success with behavioral interventions and bariatric surgery have been inconsistent. This study examined one of the important ways that obstructive sleep apnea can affect body weight. There are many things we do not understand about the relationship between obstructive sleep apnea and body weight, and this is one."

In the study conducted by Kezirian and senior study investigator Dr. Nelson B. Powell, of the University of California, San Francisco, researchers measured the number of calories burned "at rest" by 212 patients both with and without sleep apnea and all with a mean body mass index of 28.3(very overweight).

They found that volunteers expended 1763 calories a day but the people with the worst sleep apnea symptoms expended 1999 and those with mild sleep apnea expended 1626 calories. The extra calories expended roughly translate to the same as a vigorous 30 minute workout in the gym.

Dr. David Rapoport, director of the sleep program at New York Universitys Langone Medical Center in New York City said, "What they're saying is that these people have a higher metabolic rate which is not accounted for by their being overweight," he said. "People may be sleeping less and burning up more calories or are struggling to breathe and burning up more calories."

Kezirian said, "The combination of sleep deprivation and the surges of adrenaline could contribute to the increased metabolic rate during the day," he speculated.

"We have to do more studies to confirm this and to find out exactly what's going on," said Josephson. "[But] this study is important. It shows that people are starting to take this more seriously, and there is good reason to do so. Sleep apnea is the number one cause of heart attack and stroke in patients that have either while sleeping. We also know that snoring is the number one medical cause for divorce."

Professor John Stradling, a sleep expert from the John Radcliffe Hospital in Oxford, said that the study findings were "entirely plausible. If you have sleep apnoea, you are very sleepy during the day, and demotivated to do any exercise - we also know that sleep deprivation increases appetite and decreases willpower."

The study was published in the December issue of the Archives of Otolaryngology Head & Neck Surgery.