A Word About Melatonin
(From the Archives, May 2019)
by Chris McGinnis, PhD, BCBA-D
Melatonin is a naturally occurring hormone released primarily by the pineal gland deep within the brain, triggered by a complex mix of environmental time cues like sundown and your nightly routine. Contrary to popular belief, it does not make sleep happen, but it does let the rest of the brain know that it's almost bedtime.
Melatonin is produced usually without problem when a person's sleep schedule is consistent and environment and behavior within an hour or so of bedtime are pretty consistent with that of human beings centuries ago: when the sun goes down, there are no bright light sources, it's cooler than during the day, and there's not much else to do but sleep now. Of course, modern living includes flood lamps in the kitchen, a consistent set temperature, hot baths in the evening, and electronic screens everywhere, so we're now far away from our humble past when it comes to the sleep environment.
Well over 3,000,000 Americans now take synthetic over-the-counter (OTC) melatonin, and besides fish oil it is the most popular supplement taken by children. It's a $400,000,000 industry. As popular as it is, it might be worth ensuring that what is in the bottle is consistent with what the bottle says is in it.
Enter a study in the Journal of Clinical Sleep Medicine in 2017, among others, which revealed startling news. Analyzing samples of OTC melatonin in stores within one Canadian city, the researchers discovered that 70% of the products analyzed contained less than 10% of the dosage claimed on the packaging.
Such a finding might prompt one to argue that, well, less is better. This, however, could also make one assume that if you are not getting the effect hoped for, one might double or triple up on the dosage. Here's the problem: some products tested at 465% HIGHER of a dosage than that claimed on the packaging.
I would argue that one should receive what is advertised, particularly when it is a medicinal substance given routinely to children. FDA-approved pharmaceuticals are much more reliable in terms of getting what you pay for, but as I recently discovered, there are as of yet no FDA-approved, prescribed melatonin products for US consumers.
The good news is that a number of manufacturers of synthetic melatonin are producing it under Good Manufacturing Practice (GMP) standards which predicts more reliability in terms of dosage and, in turn, safety.
Synthetic melatonin is known to reduce fertility and gonadal size in rodents and primates. Short-term studies on humans appear to show that melatonin is reasonably safe, but the long-term effects are unknown. Notably, however, synthetic melatonin is known to interfere with diabetes and blood pressure management. It also inhibits REM sleep, a critical sleep stage during which neural connections made during the previous day are strengthened for better memory and focus tomorrow.
All that said, a good rule of thumb is to aim for a good, natural sleep each night without melatonin as a crutch. Behavioral treatment of childhood bedtime and sleep problems enjoys a very high success rate, especially with younger children. So, alternatives to OTC chemicals exist for better sleep. Be sure to ask your child's pediatrician for more information.
But if you or your physician insists on using OTC melatonin, look for a product manufactured consistent with GMP standards.
Dr. McGinnis is a family psychologist and a founding member of the Society of Behavioral Sleep Medicine. His practice is based in Jupiter, Florida. His website is www.mcginnisbehavioral.com.