Nothing beats a good night’s sleep.

Medical research has linked quality sleep to everything from fighting obesity and diabetes to warding off depression. But new findings reveal that just as researchers are discovering more about the healing power of sleep, they are also learning just how widespread sleep problems are around the world.

Twenty percent of adults in Canada and the United States suffer from insomnia or other severe sleep problems, and the condition has long been seen as a first-world problem.

But a new study published in the journal Sleep includes the first-ever analysis of sleep problems in Africa and Asia and estimates that 150 million people worldwide suffer from sleep anomalies. In Bangladesh, for instance, nearly 44 percent of women reported sleep problems — more than twice the rate in the Western world.

Besides Bangladesh, Vietnam and South Africa had the highest percentage of people who have difficulty sleeping among the countries studied. India and Indonesia reported relatively few problems. But one trend became apparent: Across cultures, sleep problems are most pronounced among women and the elderly.

The widespread nature of sleep issues is even more worrisome given the health problems associated with not catching enough Z’s. Diabetes rates are increasing around the world, and research has shown that people with diabetes have a harder time controlling insulin levels when they aren’t sleeping well.

Improving sleep, on the other hand, can have positive effects: Proper sleep has been shown to reduce the risk of diabetes in teenagers.

Researchers also discovered something that people who struggle with sleep have in common, no matter where they live: This problem is most prevalent in people who suffer from depression and anxiety. It’s a small world, after all.