Scientists have discovered a surprising connection between long-term melatonin use and heart failure in patients with chronic insomnia.
A recent study presented at the American Heart Association's Scientific Sessions 2025 found that taking melatonin for a year or more can increase the risk of heart failure, hospitalization, and death.
Marketed as nature’s sleep switch, melatonin has become a nightly habit for millions.
Author's summary: Melatonin may harm the heart in insomnia patients.