Your Melatonin May Be More Powerful Than Its Labels Suggest

melatonin held in a palm

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A study found that 22 of 25 supplements were mislabeled.

Taking a melatonin gummy before bed is a nighttime ritual practiced by a rapidly growing number of Americans. The hormone, when administered at the right levels, may help you fall asleep faster and toss and turn less. But according to a new study, many popular supplements contain far more of the substance than advertised. Here’s what you need to know about these popular sleep aids — and if melatonin is safe to keep using.

Melatonin’s labeling problem

Researchers from Cambridge Health Alliance and the University of Mississippi tested 25 melatonin supplements, which they purchased online from major retailers like Amazon, Walmart, and Walgreens. They discovered that 22 of those products had levels of melatonin that differed from what was listed on the label. The study, published this week in the Journal of the American Medical Association, found that one brand didn’t contain any melatonin at all, but did have a considerable amount of cannabidiol (CBD), a compound found in marijuana. Another had 347 percent more melatonin than advertised. All but four of the tested supplements had levels higher than what was listed on their bottles. (The study did not disclose the names of the brands they analyzed.)

The findings really illustrate the lack of oversight in the supplement industry. In the U.S., melatonin and substances like vitamins, probiotics, and fish oil are considered dietary supplements and don’t need to be approved by the Food and Drug Administration before they hit shelves. However, some companies do have their pills and oils verified by third-party testing orgs like U.S. Pharmacopeia (USP) and NSF, the Washington Post reports

How much melatonin is safe?

Melatonin is a hormone that helps regulate our biological clocks. When more of it’s released it signals to our body that it’s time to turn in for the night. Research indicates that taking melatonin before bedtime can help the body ease into sleep mode. 

For those interested in trying the supplement, David N. Neubauer, an associate professor of psychiatry and behavioral sciences at Johns Hopkins University, told the Post that he typically recommends starting with 1 to 3 milligrams. (The strongest gummy tested in the study contained 13.1 milligrams.) Experts also recommend asking a pharmacist to help you choose a trusted brand or finding one that’s been vetted by the USP or NSF, and, of course, to consult your doctor. 

There’s not a lot of research about how large doses of melatonin affects adults, but scientists say it’s unlikely that it’s dangerous, the New York Times reports, although some patients have reported unsettling dreams or feeling groggy the next morning. There is, however, growing concern about its effects on children, thousands of whom have mistaken these fruit-flavored supplements for candy. An alarming report published last June by the Centers for Disease Control found that melatonin-related calls to poison control spiked 530 percent from 2012 to 2021.

“It continues to be problematic to me that we put dietary supplements unregulated by the FDA, such as melatonin…in a form that is attractive to kids,” Sarah Ash Combs, an emergency medicine physician at Children’s National Hospital, told STAT.