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Yes, studies have found some melatonin supplements contain mislabeled doses

To ensure you get the right dose, experts recommend looking for brands with a USP verified seal when shopping for dietary supplements, including melatonin.

Many people take melatonin supplements, or give their children melatonin supplements, to help them sleep. They typically come in pills that you swallow or dissolve on your tongue, or gummies that you can chew.

Recently, Google searches about mislabeled melatonin and a melatonin gummy study have been on the rise. Heidi texted VERIFY to ask if it's true melatonin dosage numbers are incorrect on labels.


Have studies found some melatonin supplements contain mislabeled doses?



This is true.

Yes, studies have found some melatonin supplements contain mislabeled doses.

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A peer-reviewed study in late April 2023 found that the majority of melatonin gummy brands contained quantities of melatonin that differed from the quantity advertised on the label.

Melatonin is a hormone your brain produces in response to darkness that helps regulate your sleep cycle, the National Institute of Health (NIH) says. People take supplements to increase the amount of melatonin in their bodies. Melatonin supplements may help with certain conditions, such as jet lag, delayed sleep-wake phase disorder, some sleep disorders in children, and anxiety before and after surgery, the NIH says.

The study on melatonin doses, published in a research letter to the Journal of the American Medical Association (JAMA), found that 22 out of 25 of the melatonin gummy products analyzed were inaccurately labeled. A gummy brand was classified “inaccurately labeled” if its individual gummies contained melatonin quantities that differed from what was listed on the bottle by more than 10%.

“In products that contained melatonin, the actual quantity of melatonin ranged from 74% to 347% of the labeled quantity,” the researchers said. One melatonin gummy brand didn’t actually have any melatonin in it at all.

This is not the first study to find melatonin products commonly have inaccurate labels. The researchers referenced a 2017 Canadian study that found similar results. The Canadian study’s analysis of 16 Canadian melatonin brands — which included liquids, capsules, tablets and gummies — found that the actual melatonin dose ranged from 17% to 478% of the labeled quantity.

The 2017 study found that the melatonin supplement that diverged the most from its labeled dose, the one that was 478% of the labeled quantity, was in the chewable category, which includes gummies. The American Academy of Sleep Medicine says gummies are the form of melatonin supplement that children are most likely to use.

While the appropriate melatonin dosage can vary depending on a person’s age and symptoms, the Sleep Foundation says the typical dosage ranges from 1 to 5 milligrams for adults. Doses lower than 1 milligram may be effective for certain sleep problems.

Scientists say short-term use of melatonin supplements appears to be safe for most people, but there isn’t enough research to make any conclusions about the effects of its long-term use.

Melatonin supplements are sometimes used as a long-term treatment option for sleep issues in children with certain conditions, such as learning disabilities like autism and ADHD. The NIH says there are few studies on melatonin supplements and how they impact children. There are uncertainties about what dose to use and when to give it, the effects of melatonin use over long periods of time and whether melatonin’s benefits outweigh its possible risks. 

Melatonin can cause adverse reactions at higher doses, but the supplement is unlikely to cause a lethal overdose, the Sleep Foundation says. Side effects of melatonin such as headaches, stomach cramps, dizziness and mood changes are more likely when taken in higher doses.

The National Capital Poison Center says adverse effects of taking too much melatonin are typically mild, and “significant toxicity is not expected to occur.” Still, a National Capital Poison Center review of pediatric melatonin ingestions reported to the Poison Center between 2012 and 2021 found that 1.6% of reported ingestions resulted in more serious outcomes. Five children required mechanical ventilation, and two children under 2 years old died.

NIH tells consumers they should remember the Food and Drug Administration (FDA) regulates dietary supplements less strictly than they do prescription or over-the-counter drugs.

The FDA does not have the authority to approve dietary supplements or their labeling before the supplements are sold to the public, the FDA says. But the FDA does periodically inspect dietary supplement manufacturing facilities and review labels after the products are put on the market. If the supplement is unsafe or doesn’t otherwise comply with the law, the FDA can work with the company to bring the supplement into compliance, ask the company to voluntarily recall the supplement or take action to remove the supplement from the market itself.

The United States Pharmacopeia (USP) is an independent, scientific nonprofit organization that sets standards for medicines in the United States. While the law requires pharmaceuticals to meet USP standards, the same requirements don’t apply to supplements, the USP says.

Still, the USP does review dietary supplements for quality, including verification that the product contains the ingredients listed on the label and in the declared strength and amounts. If you use melatonin, or purchase it for someone else to use, the American Academy of Sleep Medicine and other experts recommend looking for melatonin bottles marked with the USP “Dietary Supplement Verified” seal.

You can see what the USP seal looks like here.

“A USP stamp on the bottle, Cohen says, vastly decreases the likelihood of too much or too little melatonin in a supplement,” the JAMA study’s lead researcher told Consumer Reports in an interview. “‘But even if it has a USP stamp, that doesn’t mean it will be effective,’ he says.”

There are three verified melatonin supplements listed on the USP’s website. The verified supplements are the 3 mg and 5 mg tablets from NatureMade, and the 5 mg fast-dissolve tablets from Natrol.

Melatonin is not the only dietary supplement that could have mislabeled doses, says Carl Baum, M.D., professor of pediatrics and emergency medicine at Yale School of Medicine.

"This is true of all dietary supplements, not just melatonin — this is one of 90,000 some odd products," Baum said. "So you really have to be careful when you're going out there. Something that even looks natural, may not be safe and may not be effective."

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