The researchers now plan to work out which low-fat diets are particularly good at slimming down the tongue.
Sixty-seven subjects were enlisted for the latest study, all obese with mild to severe sleep apnea. His research team compared the upper airway anatomy of Chinese and Icelandic patients with sleep apnea, and found that, compared to Icelandic patients of similar age, gender, and symptoms, Chinese patients had smaller airways and soft tissues, but bigger soft palate volume with more bone restrictions.
"Most clinicians, and even experts in the sleep apnea world, have not typically focused on fat in the tongue for treating sleep apnea", says co-author Richard Schwab, chief of Sleep Medicine at the University of Pennsylvania.
Sleep apnoea is a common disorder that can cause loud snoring, noisy breathing and jerky movements when asleep. On average, the participants lost almost 10% of their body weight over six months, which resulted in a 31% improvement in sleep apnea.More news: Harry and Meghan to begin ‘new life’ after ‘transition period’, says Queen
"Our study is the first to show that weight loss decreases tongue fat in patients with sleep apnea, which explains an important mechanism for the improvements in sleep apnea with reductions in weight", Dr. Schwab said.
Currently, scientists - including those from the University of Pennsylvania in the United States - used magnetic resonance imaging (MRI) to measure the effect of weight loss on the upper airway in obese patients.
Study participants underwent lifestyle modification for weight loss (n=49) or bariatric surgery (n=18).
Standard polysomnography and MRI studies were conducted before and after the weight-loss intervention. The fat mostly accumulates toward the back of the tongue, which may raise the likelihood that the squishy tissue will block the throat during sleep, according to the new study.More news: Celtics start strong, but lose third straight game, 109-98 to Sixers
The study also found that weight loss resulted in reduced pterygoid (a jaw muscle that controls chewing) and pharyngeal lateral wall (muscles on the sides of the airway) volumes.
To understand how weight loss affected the upper airway and abdominal fat, the researchers assessed Pearson's correlations between percent changes in weight and anatomical structures. Overweight and obese people may make up as much as 70% of those with OSA, and weight loss reliably eases the symptoms of the disorder and sometimes resolves the problem altogether, according to a 2006 study. They also explored the role genetics may play in causing sleep apnea, and suggested that people of certain ethnicities may be predisposed to having fattier tongues. "If only fat tissue was removed, coblation could be more effective". These tests were carried out using MRI scanning. Also, the study included medical and surgical weight loss.
This study was supported by the National Institutes of Health.More news: Kentucky Police arrest GM engineers street racing C8 Chevy Corvettes