Researchers gave a group of elderly insomniacs melatonin and found that the hormone significantly improved sleep maintenance, compared with a placebo.
In another study, 35 elderly insomniacs were given either 2 milligrams of melatonin or a placebo two hours before they went to bed. The groups were tested for two weeks. Those taking melatonin reported the most improvement in sleep patterns.
In a 1995 study in Israel, older people with sleep problems were given melatonin two hours before bedtime for seven days. Then researchers monitored the subjects' sleep and wake patterns. Melatonin, the scientists concluded, was effective for improving sleep maintenance.
A study in the journal Lancet suggested that controlled-release melatonin may help older people to stay asleep. Israeli researchers asked 12 people in their 70s and 80s, all of whom weren't producing enough melatonin at night, to take either placebo tablets or tablets that slowly release 2 milligrams of melatonin. After three weeks, the melatonin takers were falling asleep somewhat faster, waking for shorter periods after falling asleep, and spending more time asleep.
Still other studies have confirmed previous reports of melatonin's efficacy:
- A 1994 trial reported in the journal Neuroreport found that melatonin helped insomniacs to fall asleep nearly two hours sooner than usual.
- A 1995 study in the European Journal of Pharmacology showed that melatonin even improves napping. Young adults were treated with 3 to 6 milligrams of melatonin or a placebo. Those taking melatonin reported that they were able to get to sleep sooner and stay asleep longer than placebo-taking subjects. The melatonin group members also assessed the quality of their sleep as "deeper" than normal.
- Ten healthy young men were given tablets containing fast-release melatonin, controlled-release melatonin, or a placebo at 11 a.m. In the afternoon, they were asked to take naps. Those taking melatonin reported that the supplement helped them to fall asleep more quickly and to sleep better than usual.
- Researchers gave melatonin to 225 insomniacs and monitored their progress. Within three days, the subjects receiving melatonin reported significantly better quality of sleep and a feeling of "freshness" in the morning.
One metanalysis (a review of multiple studies that treats all the data as if it were part of one large study) did conclude that melatonin is ineffective for jet lag. However, this metanalysis was biased by a few negative studies. Still, the study found melatonin safe to use. Further research is needed, but melatonin should be viewed as a safe alternative to treat insomnia or jet lag.