Millions of people may be taking melatonin as a sleep aid, but the hormone has not been scientifically proven either effective or safe, specialists said Monday at the National Institutes of Health.
Researchers at a conference on the use of melatonin said publicity about the presumed benefits of the hormone has created a brisk market even as scientists are scrambling to determine if it has serious side effects.
Melatonin is unregulated under federal law because it is a natural ingredient in some foods.
But the compound is also a natural hormone produced by the pineal gland in the brain. Studies 20 years ago showed that the natural levels of melatonin increase 10 times just before and during sleep.
More recent studies have suggested that the hormone can reset the sleep-wake cycle, and thus help overcome the effects of jet lag or night shift work.
But none of these studies has been scientifically conclusive, said Dr. Richard Wurtman of the Massachusetts Institute of Technology. “We need to go through testing to determine correct dose and the efficacy,” said Wurtman. He said people should not buy the hormone because its purity and dosage are not assured.
