Long-term Melatonin Use May Pose Health Risks
A review of health records spanning five years and involving over 130,000 adults with insomnia who used melatonin supplements for at least one year revealed increased risks associated with prolonged use.
Key Findings
- Higher likelihood of being diagnosed with heart failure
- Increased chances of hospitalization due to heart failure
- Elevated risk of death from any cause among chronic insomnia patients
Study Context
This preliminary research was presented at the American Heart Association's Scientific Sessions 2025, held in New Orleans from November 7 to 10. The event showcases recent advances and clinical updates in cardiovascular science.
About Melatonin
Melatonin is a natural hormone produced by the pineal gland that regulates the sleep-wake cycle. Its levels rise during darkness and fall with daylight.
Synthetic melatonin supplements, chemically identical to the natural hormone, are widely used to help with insomnia and jet lag. They are available over the counter in many countries, including the United States.
Supplement Quality Concerns
In the U.S., over-the-counter melatonin supplements do not require government approval for quality or consistency, so their strength and purity can vary significantly between brands.
“Long-term use of melatonin supplements was associated with a higher risk of heart failure diagnosis, heart failure hospitalization and death from any cause in chronic insomnia.”
Author’s summary: Long-term melatonin supplementation for insomnia may increase heart failure and mortality risks, highlighting the need for cautious use and quality control.