Melatonin has been assumed, logically enough, to have some use as a sleeping pill. Here are some questions, facts, and mysteries. The answer, until recently, was thought to be yes. But a new study at the Harvard Medical School of healthy people taking no medications or drugs found no differences in melatonin levels between the young and old. In earlier studies medications such as aspirin taken by older people may have suppressed melatonin levels.
Different people have different levels, and levels vary according to time of day.
No one knows what the long-term effect might be. Most scientists agree that melatonin helps people fall asleep faster, but it may not help them stay asleep. Long-term safety is still a question. Melatonin is being heavily marketed as a sleeping pill, particularly for older people, but nobody knows if the dosages listed on labels are accurate or if the products are pure. Good clinical trials have never been done on melatonin treatment for insomnia.