A Common Supplement Displays a Concerning Link to Heart Failure

Key Points:

• Preliminary research presented at the American Heart Association's Scientific Sessions links long-term melatonin prescription (over one year) to an 89% higher risk of heart failure and nearly double the risk of death within five years among adults with insomnia.
• The study analyzed health records of over 130,000 adults across multiple countries, finding those prescribed melatonin long-term were 3.5 times more likely to be hospitalized for heart failure compared to non-users.
• Despite melatonin's widespread over-the-counter availability and perception as a safe sleep aid, these findings suggest potential serious health risks from prolonged use, prompting calls for more comprehensive and controlled research.
• Limitations include reliance on prescription records rather than direct surveys of melatonin use, meaning some control group members may have used melatonin without prescriptions, complicating the results.
• Saudi Arabia's drug regulator issued a formal safety signal regarding melatonin and heart failure in April 2026, highlighting growing regulatory concern, although melatonin remains considered safe for short-term use (1-2 months) in non-pregnant adults.