White bottle and pills, letters Melatonin, alarm clock and sleep mask on light grey background

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Are you one of the one in three Americans who struggle to get the recommended amount of sleep? As sleep problems are made worse by pandemic stresses, many are turning to popular sleep aids, such as melatonin supplements, to help catch Z’s.

According to NielsenIQ, Americans spent over a billion dollars on melatonin supplements last year, and high-dose melatonin use has tripled since 1999. But is this sleep aid safe? We asked Dr. Smita Patel, an integrative neurologist and sleep medicine physician who is a member of HealthyWomen's Women's Health Advisory Council, to learn more.

What is melatonin?

We naturally produce melatonin, a hormone that helps regulate our sleep cycle or “circadian rhythm” — the 24-hour cycle of sleep and activity. Melatonin production peaks in the evening when the sun goes down, signaling to our bodies that it's time for bed. In the morning, as our melatonin levels decrease, we begin to wake up.

The most important factor for melatonin production is light exposure. “Light is the part that sets the rhythm,” Patel said. She further explained that synthetic light can disrupt melatonin production. “Once our bodies see light in the evening, melatonin production shuts down. That’s why we want to try to minimize the light in the evening as [much as] possible just to try to keep our circadian rhythm in check.”

Melatonin is naturally synthesized from serotonin, a neurotransmitter, in the pineal gland in our brain. While humans make melatonin on our own, we can take it too — as an over-the-counter (OTC) dietary supplement in gummy, liquid or capsule forms. Melatonin supplements can be made synthetically or by using animals and microorganisms.

Does synthetic melatonin work?

Research shows that melatonin supplements improve sleep quality, but more studies are needed to understand the long-term effects of melatonin supplements. We also don’t know the risks for high-dose melatonin use. Check with your healthcare provider (HCP) about how much melatonin would be right for you.

Research shows melatonin supplements help these conditions:

Melatonin supplements shouldn’t be used to counteract the detrimental effects of late-night screen time. “It’s not like ‘consume the media and then take a melatonin.’ I wouldn’t use it like that. I would actually use it more for people who are off cycle, who need help going to bed on time or if they need to travel,” Patel advised. “It’s like putting your hand in a hot fire and then putting it in an ice bath.”

Side effects of melatonin supplements can include headache, dizziness, nausea and irritability. And melatonin use has also been linked with vivid dreams or nightmares; this may be because melatonin causes the body to stay in deeper sleep for longer, as the deepest stage of our sleep cycle, the REM cycle, is generally associated with more intense dreaming.

Warnings about melatonin

The U.S. Food and Drug Administration does not regulate supplements, including melatonin, and a recent study found that more than 71% of melatonin supplement brands did not contain what their label advertised. Even more, 26% of surveyed melatonin supplements contained serotonin, a dangerous contaminant that can cause fatal overdose, even at low levels.

This study underlines the importance of making sure your supplements come from reliable companies. Patel recommends looking for third-party verifiers on your melatonin supplement’s packaging. Common third-party verifiers include United States Pharmacopeia (USP), NSF International, Underwriters Laboratories or Consumer Labs.

It’s always best to consult with your HCP before beginning any type of supplement, and those who are pregnant, breastfeeding, or have an autoimmune disorder should stay away from melatonin.

As helpful as melatonin supplements can be, it’s important to remember that light exposure is much more powerful. Strategically reducing light exposure and avoiding light sources as your bedtime gets closer can have a large impact on your ability to get to sleep on time.

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