Melatonin and Sleep
Wednesday, January 1, 2014
levels in the blood to rise to much higher levels than are naturally produced in the body. Taking a typical dose (1 to 3 mg) may elevate your blood melatonin levels to 1 to 20 times normal. Side effects do not have to be listed on the product's packaging. Yet, fatigue and depression have occasionally been reported with use of melatonin.
When given to animals, melatonin can cause changes in blood pressure and affect fertility. Such effects in humans would be a medical risk for people with heart-related problems, hypertension and stroke, kidney disease and sleep apnea as well as for women of child-bearing age.
For melatonin to be helpful, the correct dosage, method and time of day it is taken must be appropriate to the sleep problem. Taking it at the "wrong" time of day may reset your biological clock in an undesirable direction. How much to take, when to take it, and melatonin's effectiveness, if any, for particular sleep disorders is only beginning to be understood.
While there are real concerns about the widespread use of melatonin sold as a consumer product, there have not been any reported cases of proven toxicity or overdose.
For some people, melatonin seems to help improve sleep. However, when scientists conduct tests to compare melatonin as a "sleeping pill" to a placebo (sugar pill) most studies show no benefit of melatonin. Evidence that melatonin can reset the body clock is more well established, although it is not clear whether exposure to light may be more effective. Overall, research indicates improved sleep when melatonin is taken at the appropriate time for jet lag and shift work. Appropriate dosage and any safety risks will become clear with further research.
Some studies show promise for the use of melatonin in shortening the time it takes to fall asleep and reducing the number of awakenings, but not necessarily total sleep time. Other studies show no benefit at all with melatonin.
Melatonin might help shift workers on irregular shifts who need to adjust their schedules. When taken in low doses at the appropriate time, melatonin