Long-term Melatonin Use and Health Risks
A review analyzed five years of health records for over 130,000 adults with insomnia who used melatonin supplements for at least one year. The study found a higher likelihood of being diagnosed with heart failure, increased hospitalizations for heart failure, and greater risk of death from any cause among chronic insomnia patients using melatonin.
Study Presentation and Context
This preliminary research will be presented at the American Heart Association’s Scientific Sessions 2025, held in New Orleans from November 7 to 10. The event is a leading global forum for the latest cardiovascular science and clinical practice updates.
About Melatonin
Melatonin is a hormone naturally produced by the pineal gland that regulates the sleep-wake cycle. Its levels rise in darkness and fall in daylight. Synthetic melatonin supplements, chemically identical to the natural hormone, are commonly used to treat insomnia and jet lag.
- Widely available over the counter in many countries, including the U.S.
- In the U.S., these supplements do not require government approval for quality or consistency.
- Supplements can vary significantly in strength and purity depending on the brand.
“Long-term use of melatonin supplements, often used to promote sleep and address insomnia, was associated with a higher risk of heart failure diagnosis, heart failure hospitalization and death from any cause in chronic insomnia.”
Melatonin use should be approached with caution, especially for long-term sleep support in patients with chronic insomnia.
Author's summary: Prolonged melatonin supplementation for insomnia may pose serious risks including heart failure and increased mortality, emphasizing the need for cautious use and further research.