Prime Highlights
- A global study presented at the 2025 American Heart Association Scientific Sessions revealed that prolonged melatonin use may significantly increase the risk of heart failure and death.
- Experts warn that melatonin should not be used long-term and urge individuals with chronic insomnia to seek medical advice and evidence-based treatments like CBT-I.
Key Facts
- The five-year study of over 130,000 adults found that those using melatonin for more than a year had a 90% higher risk of heart failure.
- 19%of long-term melatonin users were hospitalized for heart failure compared to 6% of non-users, while 7.8% of users died versus 4.3% of non-users.
Background
A global study found that taking melatonin supplements for a long time may greatly raise the risk of heart failure and death. The study’s results were presented at the 2025 American Heart Association Scientific Sessions in New Orleans.
In a five-year study of more than 130,000 adults suffering from insomnia, researchers found that individuals who took melatonin for longer than a year faced a 90% greater risk of heart failure and were nearly twice as likely to die from any cause compared to those who did not use the supplement. The study was led by Dr. Ekenedilichukwu Nnadi at SUNY Downstate/Kings County Primary Care.
The American Heart Association reported that 19% of people who used melatonin long-term were hospitalized for heart failure, compared with 6.6% of those who did not use the supplement. The death rate among users was also higher, 7.8% versus 4.3%. The results stayed the same even after researchers considered age, gender, and existing health conditions.
Experts explained that the body naturally makes melatonin to control sleep, but melatonin supplements often have much higher doses than the body’s normal levels. These excessive amounts may disturb the cardiovascular and metabolic systems.
Dr. Marie-Pierre St-Onge, Professor at Columbia University and Chair of the AHA’s 2025 Sleep Health Committee, said that melatonin should not be taken for long periods and is not approved for treating chronic insomnia. She stressed that users should consult doctors instead of stopping suddenly.
Health experts advise people to improve sleep habits by keeping regular sleep schedules, avoiding screens before bed, and cutting back on caffeine. For those with long-term insomnia, cognitive behavioral therapy for insomnia (CBT-I) is the safest and most effective treatment.
