Science | Lab test
Most Melatonin Gummies Tested Did Not Contain What Their Labels Said
In a JAMA study, 22 of 25 products were off, one by more than three times the stated dose. This year, a magnesium gummy was recalled for melatonin it never listed at all.
If you take a melatonin gummy at night, you probably trust the number on the bottle. A study in JAMA suggests that, for most gummies, you should not.
Researchers led by Dr. Pieter Cohen of Cambridge Health Alliance and Harvard Medical School bought melatonin gummies sold in the US and measured what was inside them. Of 25 products, 22 did not match their labels.
How the test worked
The team searched the National Institutes of Health's Dietary Supplement Label Database in September 2022 and tried to buy 30 brands online. Four were unavailable and one did not list melatonin, which left 25 products. The gummies were then analysed in a laboratory at the University of Mississippi.
What they found
- 22 of 25 products, 88%, were inaccurately labelled.
- Actual melatonin ranged from 74% to 347% of the amount on the label.
- Only 3 products were within 10% of the label.
- Five products also listed CBD. In those, CBD measured 104% to 118% of the stated amount.
- One product contained no detectable melatonin at all, and 31.3 mg of CBD.
The authors warned that, taken as directed, these gummies could expose children to 40 to 130 times more melatonin than the body produces.
What the study could not show
The researchers tested one gummy from each brand, so the study cannot say how much batches vary. It covered gummies only, not tablets or capsules. The Council for Responsible Nutrition, an industry group, disputed the paper.
When the melatonin is not on the label at all
In 2026, Dkiru LLC recalled Adndale Magnesium Glycinate Gummies 400 mg because they contained melatonin that was not declared on the label, according to ConsumerLab. The Class II recall covered 13,920 bottles from lots 190824, 240923 and 240929, sold on Amazon and on the brand's own website.
For anyone who takes magnesium precisely to avoid melatonin, that is the worst kind of surprise.
What you can do
In the US, melatonin is sold as a dietary supplement and does not need FDA approval before it reaches the shelf. The American Academy of Sleep Medicine suggests looking for the USP Verified Mark, which shows a product has been independently tested to contain what its label says.