Amounts of melatonin in supplements can vary widely from what’s on labels: study
TORONTO — Researchers have measured levels of melatonin in a number of over-the-counter supplements sold in Canada and found amounts of the hormone can vary dramatically from what’s listed on the products’ labels.
Melatonin is produced in the brain and occurs naturally in small quantities in some meats, grains, fruits and vegetables. Supplements containing melatonin are often taken by people in a bid to overcome sleep problems.
A study by the University of Guelph, published this week in the Journal of Clinical Sleep Medicine, tested 30 melatonin supplements produced under 16 brand names and sold in grocery and drug stores.
The researchers found 71 per cent of the products — which were not identified by name — did not meet label claims. Higher-than-listed amounts of melatonin ranged between 12 and 25 per cent on average, but some products had nearly five times the hormone they were said to contain.