Over the years, there have been reports on various benefits of the so-called Mediterranean diet — a style of eating that focuses on the consumption of healthful monounsaturated fats, fruits, vegetables, whole grains, low-fat dairy, fish, nuts, and legumes, as well as moderate daily consumption of alcohol and a relatively low intake of red meat. In previous studies, this eating pattern has been shown to have wide-ranging benefits, including reduction in the rates of Type 2 diabetes, cardiovascular disease, obesity, metabolic syndrome, and some types of cancer. Now, a small new study indicates that the Mediterranean diet, combined with exercise, has another benefit: potentially reducing the symptoms of sleep apnea.
Sleep apnea is a condition in which breathing stops for 10 seconds or more during sleep, sometimes hundreds of times a night. The disorder affects approximately 18 million people in the United States, and has strong links with diabetes: People who have sleep apnea are more than twice as likely as those who don’t to have diabetes, and 50% of men with Type 2 diabetes have sleep apnea.
To determine the effects of a Mediterranean-style diet on the symptoms of sleep apnea, researchers from the University of Crete in Greece randomly assigned 40 obese people with the condition to follow either a “prudent” diet or a Mediterranean diet. Participants in both groups were also encouraged to increase their physical activity, mostly by walking for at least 30 minutes a day, and additionally received continuous positive airway pressure (CPAP) therapy (a sleep apnea treatment that involves wearing a mask that uses a stream of air to keep the upper airway open during sleep). The participants were monitored during a sleep study that checked for markers of sleep apnea, including activity in the brain, eye movements, and snoring, both at the beginning of the study and again six months later.
The results showed that those following the Mediterranean diet had a reduced number of apneas, or pauses in breathing, during the REM stage of sleep, which accounts for roughly 25% of sleep during the night. Those assigned to the Mediterranean diet group also had a greater adherence to the diet, a greater decrease in abdominal fat, and an increase in physical activity compared to the “prudent” diet group. However, the study did not show an overall improvement in the severity of sleep apnea among those in the Mediterranean diet group.
Lead study author Chrisopther Papandreou, RD, PhD, noted that “Our results showed that the number of disturbances during REM sleep was reduced more in the Mediterranean diet group than the other group. Recent reports have related an increase in disturbances during REM sleep with the risk of developing significant systemic consequences like [Type 2] diabetes.” Papandreou further noted that more studies with larger numbers of participants are necessary to identify the exact relationship between the Mediterranean diet and sleep apnea.