Research suggests that a good night’s sleep has tremendous positive impact on brain functions, metabolic processes and immune system function. However, as many as 50% of Canadian adults experience sleep problems. One reason may be insufficient production of melatonin, the hormone that prepares the body for sleep by lowering temperature and alertness.

German researchers evaluated the effects of melatonin on those with disturbed REM sleep. (REM, or rapid eye movement, signals a deep stage of sleep.) Fourteen male and female outpatients with reduced REM sleep participated in two consecutive trials. Patients received either placebo or 3 mg melatonin daily for four weeks, administered between 10 and 11pm. The results show melatonin was significantly more effective than placebo: patients on melatonin experienced increases in both REM sleep and daytime functions. These results were confirmed in the patients who received melatonin in the second study. The researchers concluded that melatonin helps normalize sleep cycles and may therefore improve general health.

At the National Institute of Mental Health and Neurosciences in India, researchers found that melatonin may be a useful for medically ill patients with insomnia. In this study, 33 medically ill persons with insomnia were randomly given either melatonin or placebo. Sleep assessments were obtained daily over the next two weeks. Relative to placebo, melatonin significantly hastened sleep onset, improved quality and depth of sleep, and increased sleep duration without producing drowsiness or adverse daytime effects. Melatonin also contributed to improved overall daytime functioning. These benefits were most apparent during the first week of treatment.

Sources: J Clin Endocrinol Metab. 2004 Jan;89(1):128-34; J Clin Psychiatry. 2001 Jan;62(1):41-5