Melatonin is a natural hormone
Dean Drobot/ShutterstockA good night's sleep is a crucial part of a healthy lifestyle. If you struggle to get enough shut-eye through the night, you might be tempted to take melatonin for sleep. But did you know that you already have melatonin in your body? According to the National Sleep Foundation, it's a natural hormone made by the body's pineal gland, which is the size of a grain of rice and located just above the middle of the brain. During the day the pineal is inactive, meaning levels of the hormone are barely detectable. However, when the sun goes down, the pineal "turns on" and begins to produce melatonin—typically around 9 p.m. As a result, the hormone's levels in the blood rise sharply and we begin to feel sleepier. For about 12 hours—throughout the night—those blood levels stay elevated, before the light of a new day when they fall back to low daytime levels.
It's not a cure for insomnia
Andrey Popov/ShutterstockWhile the supplement may be taken to help treat sleep problems, it's not a cure for insomnia; it can help induce sleep, but it won't help you stay asleep. According to the Mayo Clinic, this supplement is effective for conditions such as jet lag, seasonal affective disorder (SAD), controlling sleep patterns for people who work night shifts, preventing or reducing problems with sleeping and confusion after surgery, and reducing chronic cluster headaches. If you respond well to the supplement, there's no reason you can't continue to take it long-term without any negative side effects, but relying on it too heavily could have a negative effect. "It can de-sensitize your receptors so they're no longer responsive to lower doses of melatonin," says Andrew Westwood, MD, a board-certified sleep physician and assistant professor at Columbia University. "Then, if you come off [the supplement], you might have difficulty sleeping—and require more and more [of it] to fall asleep."
What you see is not always what you get
BW Folsom/ShutterstockMany people who have difficulty falling asleep take an over-the-counter melatonin supplement, which doesn't require the FDA stamp of approval. While there's no cause for panic—in general, melatonin is considered safe—this means very high doses can be sold, sometimes containing unknown additives. "These can have unwanted drug-like effects or unwanted side effects," says Brunilda Nazario, MD, associate medical director at WebMD. "A dose of 0.3 or 0.5 mgs at night helps induce sleep but higher doses can produce daytime sleepiness, grogginess, reduce physical performance, and cause a decrease in normal body temperature," she says. Because the supplement isn't regulated, levels of melatonin can vary. A study published in the February 2017 issue of the Journal of Clinical Sleep Medicine revealed that the melatonin content of dietary supplements often varies widely from what is listed on the label. Sanjeev Kothare, PhD, Director of the Pediatric Sleep Center and Sleep Education at NYU Langone, adds that the risk for allergic reaction can also vary, due to the carrier in the formulation. Here are more things you might be allergic to.
There is no one recognized dose
Terry Putman/Shutterstock"As melatonin is not a prescribed medication, the range of doses available is wide and there is no one recognized dose for patients with insomnia or sleep phase disorder," reveals James A. Rowley MD, Detroit Medical Center Interim Chief, Division of Pulmonary, Critical Care & Sleep Medicine. "Thus, the patient should follow the instructions of their physician (preferably a sleep physician) on what dose they should take. Then, they need to purchase it at a reputable pharmacy or general nutrition/supplement store; they should purchase a supplement made in a lab, not from animal sources, as these are more likely to have contaminants. Finally, if they have any side effects or perceived side effects after starting the supplement, they should stop taking it and return to their physician for more assistance."
The jury's out on side effects
Agnieszka Marcinska/ShutterstockAccording to Kothare, there are no short term melatonin side effects, but some individuals experience headaches, nightmares, or lingering sedation the next morning. It's not clear whether there are long-term side effects, because the majority of studies are of short duration, often less than six months, adds Rowley. In one six-month study published in BMC Medicine in 2010, side effects were mild and did not differ significantly from side effects reported in the placebo group, says Rowley; the most common side effects were cold-like symptoms, joint pain, diarrhea, upper respiratory tract infections and headache. Sore head? Here are seven home remedies for headaches.
It may be harmful during puberty
Africa Studio/ShutterstockMelatonin works on several parts of the brain and body, including the hypothalamus and pituitary glands, which are involved in pubertal development. Nazario cautions parents to discuss their child's sleep problem with a pediatrician before giving them the supplement. "The hormone is naturally reduced during puberty and changing this pattern with an unregulated compound and without supervision can potentially result in harm," she warns. "Instead, it's critical to try and determine the cause of lack of sleep, and eliminate any contributing factors to help correct his or her sleep problems." The supplement is considered safe for children, says Kothare, and is officially indicated for children with autism, but you should always check with your doctor before giving it to your kids.
It's not the only solution
Marcos Mesa Sam Wordley/ShutterstockBefore you start taking any supplements for sleep, be aware that the problem could be solved another way. There are various treatments to help normalize sleep including ensuring good sleep hygiene. Nazario recommends going to bed at the same time every night, removing stimulants that emit blue light (yes, turn off those screens and put them far away from your bed!), and avoiding late afternoon or evening naps. "You may want to start with other natural treatments, including chamomile and hops tea or valerian root," she suggests. Check out these sleep secrets from doctors.