(The following press release was issued Monday, Feb. 28, by the National Center for Research Resources. An earlier story on the study was reported in Tech Talk on Nov. 17, 1993.)
Scientists at the MIT Clinical Research Center have shown that tiny oral doses of melatonin can put people to sleep--findings that suggests that melatonin may offer an alternative to hypnotic drugs, such as Valium, frequently used to relieve insomnia. Scientists say their results also suggest that melatonin plays a key role in inducing sleep.
"As you age, the amount of melatonin that your body secretes each evening from the pineal gland decreases and the incidence of sleeping difficulties increases. I see melatonin as being potentially useful, particularly in those who don't secrete enough of the hormone," said Richard Wurtman, MD, program director for the MIT Clinical Research Center and principal investigator in the current study. Results from the research, funded in part by the National Center for Research Resources (NCRR) and the National Institute of Mental Health (NIMH), will appear in the March 1 issue of the Proceedings of the National Academy of Sciences.
"This discovery is exciting from both basic and clinical perspectives and is a good example of what scientists can achieve given the proper research technologies and support," said Judith L. Vaitukaitis, MD, director of NCRR, which funds the MIT Clinical Research Center. "These results will help scientists to pull back the curtains that have obscured understanding of sleep. They also boost future hope for a natural, non-addictive agent that could improve sleep for millions of Americans."
Despite the promising results, consumers should not use melatonin that is sold in some health food stores, because the supplements may contain impurities and offer doses of the hormone that are "much too high," Dr. Wurtman cautions. "I am hopeful that a safe, regulated supply of the hormone may be available in the future." Extensive studies of the hormone would be needed before this would be possible.
In the placebo-controlled study, scientists gave 20 volunteers either a placebo or one of several very small (0.1-10mg) doses of melatonin and asked them to close their eyes while holding a switch in a darkened room They then measured how long it took for the volunteers to release the switch, an indication of their departure into sleep. All the various doses of melatonin significantly speeded the onset of sleep and increased time spent asleep when compared with placebo. In addition, volunteers also reported increased sleepiness and fatigue after receiving melatonin.
"All of us have wondered what makes you fall asleep and what determines when you fall asleep," said Dr. Wurtman. "These findings suggest that one answer may be melatonin."
NCRR, which funds a network of 75 Clinical Research Centers at leading academic medical centers nationwide, is part of the National Institutes of Health, located in Bethesda, MD.
A version of this article appeared in the March 2, 1994 issue of MIT Tech Talk (Volume 38, Number 24).