This is quite a wake up call.
Emerging research from the Harvard TH Chan School of Public Health has revealed that melatonin-containing sleep aid gummies may contain alarming amounts of the hormone — far more than manufacturers claim.
One brand tested contained more than 300% of the promised melatonin per serving, according to the study published on the JAMA Open Network on Tuesday, while most others were found to be “mislabeled.”
Led by supplement industry expert Dr. Pieter Cohen, the research team tested 25 different varieties of gummy sleep vitamins, some of which were marketed with misleading labels and contained higher-than-advertised doses of melatonin. as well as CBD (cannabidiol), a chemical derived from the cannabis plant that is banned by the federal government.
Touted as a remedy for sleep disorder symptoms, melatonin supplements, a hormone that plays a role in the circadian rhythm, have sparked growing interest among US consumers, with sales rising to $821 million as of 2020 .
But regulation of supplements by the Food and Drug Administration is virtually non-existent, raising concerns among experts.
“When it comes to products like melatonin that are sold in the US as dietary supplements, current law leaves consumers at the mercy of the marketplace – whatever a manufacturer puts into the product is what you get,” Cohen told The Post.
“The FDA does not test products to ensure they are accurately labeled,” he reiterated.
The agency does not have the authority to test supplements before they hit store shelves, leaving manufacturers responsible for ensuring the safety and efficacy of their products. While regulations state that all ingredients must be listed on supplement packaging, there is no industry-wide standard for serving sizes, dietary supplement dosages, and quality control.
Cohen, associate professor of medicine and internist at Massachusetts Cambridge Health Alliance, found that many of the melatonin-containing supplements tested were misleading and had higher levels of melatonin or even CBD than advertised.
This is a significant risk for children, the study authors cautioned, due to the possibility of both intentional and unintentional consumption, and the fact that we don’t have much research on the effects of excess melatonin.
Cohen’s team cited a 2022 report from the Centers for Disease Control and Prevention that saw a 530% increase from 2012 to 2021 in pediatric melatonin intake.
The report stated that the majority of pediatric calls to Poison Control were due to unintentional consumption, and in some cases, ingestion resulted in hospitalization and even death.
Inspired by the alarming data, the researchers used the National Institutes of Health’s Dietary Supplement Label Database to identify new sleep aid gummies containing melatonin and CBD.

Of the 30 chosen by the team and ordered online, only 25 made the cut. Those without “melatonin” explicitly on the label were excluded from the study.
“To our knowledge, this is the first US study to quantify melatonin in over-the-counter melatonin products,” the study authors wrote.
Of the gummy brands tested, 88% were “mislabeled,” with melatonin percentages ranging from 74% to 347% of the claimed amount. Only three products contained the approximate amount of melatonin printed on the label.
One product contained no “detectable levels” of the hormone at all, but did have just over 31 milligrams of CBD.
Five products the team investigated claimed to contain amounts of CBD ranging from 10.6 milligrams to 31.3 milligrams per serving. But, according to the study, those products contained between 104% and 118% of the declared amount of CBD.
Despite the limited scope of just 25 types of gummies, the study “represents recently introduced melatonin gummies” that are currently all the rage on the market, Cohen told The Post,

But the Council for Responsible Nutrition, an interest group of supplement manufacturers and suppliers, disputed the study’s findings that ingredient amounts are “unpredictable.”
The association asserted that pediatric doses of melatonin can be safely administered under the supervision of a physician, arguing that “supplement companies go to great lengths” to ensure the safety of their products.
“This report completely undermines a safe product when used in accordance with the manufacturer’s instructions,” Steve Mister, CRN’s president and CEO, said in a statement. “Parents know how to care for their own children and, often in consultation with their health care providers, have been safely giving the pediatric versions of these melatonin products to their children for years.”
But last year, the American Academy of Sleep Medicine urged parents to refrain from giving melatonin to healthy children because of limited evidence that it “may help healthy children or adults fall asleep faster.”
Previous studies have found inconsistent levels of melatonin present in supplements, according to Cohen’s findings.
Adults can take anywhere from 1 to 10 milligrams of melatonin, but experts caution that in addition to people tolerating different amounts, there is no standard dosage for either product. This makes overdoses, which are possible, difficult to define.
But products that receive the National Sanitation Foundation (NSF) or United States Pharmacopeia (USP) seals of approval can give consumers peace of mind. Verified supplements undergo rigorous testing to ensure that the amount of ingredients is accurate.
As a general rule, Cohen advised parents to keep gummies out of reach of children, as they would medicines like Benadryl or Tylenol, to prevent accidental ingestion.
As for adults, she told The Post that “it’s not possible to just select any melatonin gummy and assume it’s accurately labeled.”