Music does more than soothe the savage beast. It also provides relief for the irritated insomniac.

That’s the conclusion of a just-published meta-analysis by Chinese researchers, who examined 10 studies conducted on three continents. Across the globe, they report, sweet sounds induce sound slumber.

“Music appears to be effective in treating acute and chronic sleep disorders,” writes the research team, led by Chun-Fang Wang of the Department of Cardiovascular Surgery at Pingjin Hospital in Tianjin. “It is low-cost and safe, and could be used to improve sleep quality in various populations with different ages and cultural backgrounds.”

The researchers began by identifying 127 scholarly articles describing research into music and sleep. They narrowed those down to the 10 that met their criteria: All used a randomized controlled design, featured participants over 18 years of age, and involved listening to music rather than performing it.

The 10 studies—three from the United States, two from Taiwan, and one apiece from Italy, Austria, Hungary, South Korea, and Hong Kong—featured a wide range of participants, including university students, residents at a shelter for abused women, and hospital patients who had just undergone major surgery. Their music therapy lasted anywhere from one day to four weeks.

Despite all these differences, the results were strikingly consistent: Music therapy improved the quality of sleep in people with both acute and chronic sleep disorders. Results were similar for people of different ages, and in different parts of the world; they were positive both for participants who self-reported their quality of sleep, and those whose sleep was monitored using a polysomnogram.

The only exceptions were short-term studies (those lasting less than three weeks) featuring participants with chronic sleep problems. The researchers believe this was not enough time for the therapy to work on these patients.

Some of the Asian studies used traditional music from their nations' cultures, while those in Europe and the U.S. used Western classical music. But in all cases, the pieces were “characterized by a tempo of 60-80 beats per minute, slow, stable rhythm, low-frequency tones, and soothing and relaxing melodies,” the researchers write in the International Journal of Nursing Studies.

So why do these sophisticated lullabies work? “The possible underlying mechanisms are not fully understood,” the researchers concede. They note that music “acts upon the central nervous system, especially the deeper, more ancient parts of the brain such as the limbic system,” and add that some evidence suggests it can impact levels of opioids and oxytocin in the brain.

Given that an estimated 30 percent of Americans suffer insomnia at some point in a given year, this is encouraging news; it suggests music, under the right conditions, can be an effective, drug-free alternative to sleeping pills. If you’re counting sheep, perhaps you should be doing it to a gentle beat.