Study: Half of melatonin products for children list wrong concentration

Key takeaways:

• Half of products had a melatonin concentration within 23% of their labeled amount.
• The FDA recommends providers reach out directly to manufacturers with questions or concerns.

Half of melatonin products sold in the United States had significantly more or less melatonin than indicated on their labels, according to a recent study by the FDA.

Previous research has found that one in five school-aged children and preteens use melatonin as a sleep aid. The supplement was responsible for sending 11,000 children to the ED from 2019 to 2022 due to unsupervised ingestion.

In 2017, an investigation into 30 products sold in Canada found a high level of variability in the melatonin concentration in each product vs. their labels. Additionally, eight of these products had unlabeled serotonin.

In the new study, Rahul S. Pawar, PhD, a research chemist at the FDA, and colleagues tested the melatonin content in 110 melatonin products sold in the U.S., most of which were marketed for use by children, including gummies, chewable and fast-dissolving tablets, pills, liquids and other edible products like chocolate pieces and drink mixes.

Most of the products (70%) were labeled for use by children or had general instructions. However, the containers on 13 products said they were not for use by people aged younger than 18 years despite their website indicating they can be used by children and adolescents, according to the researchers.

“Such inconsistent or ambiguous directions for use by age in product label statements and online content may lead consumers to purchase an adult product for use in children,” Pawar and colleagues wrote.

Out of 110 products, 108 contained at least 0.01 mg/g of melatonin (median 1.2 mg/g; range, 0.017-130 mg/g or 0.042-50 mg/serving), the researchers found. None of the products contained serotonin.

Half of the products’ melatonin concentration was within 23% of the labeled amount, whereas 20 products contained less than three-quarters of the labeled amount and 35 products contained more than the labeled amount. One edible product had 667% more melatonin than the label indicated; the actual melatonin content was 3.3 mg/serving.

The products for children typically had a melatonin concentration of 0.2 mg/serving to 10 mg/serving on the label, and products for adults only were labeled with 1 mg/serving to 20 mg/serving.

Although most (98%) of the products reported melatonin content between 0.1 and 10 mg/serving, one had 20 mg/serving and another had 60 mg/serving.

Most of the products (71%) had child-resistant packaging.

An FDA spokesperson told Healio that dietary supplements, including melatonin products, are not approved by the FDA for safety or effectiveness, nor are their labels.

“Dietary supplement firms are responsible for ensuring that their products are safe and lawful,” the spokesperson said.

The FDA said these findings align with previous research into the accuracy of labels on melatonin products, and it will take these results into consideration when monitoring these products.

If health care providers are concerned about labels or ingredients in specific products, the FDA said it encourages them to reach out directly to supplement manufacturers.