Why in news?
A study presented at the American Heart Association’s Scientific Sessions 2025 has found that adults with chronic insomnia who regularly take melatonin supplements may be at higher risk of heart failure, hospitalization and death. The results, based on health records of thousands of patients, have sparked renewed debate over the long‑term safety of the popular sleep aid.
Background
Melatonin is a hormone produced by the brain’s pineal gland in response to darkness. It helps regulate the body’s internal clock and promotes sleep. Melatonin supplements are usually synthesized in laboratories and are widely marketed as remedies for jet lag, insomnia and other sleep disorders. Research shows they can be useful for conditions like delayed sleep‑wake phase disorder and to reduce pre‑surgery anxiety. However, supplements are regulated less stringently than medicines, and their long‑term effects are not well understood.
Study highlights
- Observational analysis: Researchers analysed medical records of adults diagnosed with chronic insomnia. They compared outcomes for those taking melatonin against those who did not.
- Increased risk: Long‑term users were about 90 percent more likely to develop heart failure than non‑users. They also faced higher rates of hospitalisation and mortality from heart‐related causes. The study could not prove causation but revealed a strong association.
- Call for caution: Doctors are urging patients to consult healthcare providers before using melatonin regularly, especially those with existing heart conditions.
Possible side effects and guidance
- Mild adverse effects: Short‑term studies report headaches, dizziness, nausea and sleepiness in adults. Children may experience drowsiness, increased urination, headaches or agitation. Serious side effects are rare.
- Unknown long‑term effects: Researchers do not yet know the consequences of taking melatonin for months or years. There is concern that prolonged use could affect hormone levels or interact with other medications.
- Safe use recommendations: People considering melatonin should start with the lowest effective dose and use it only for short periods. Consultation with a doctor is advisable, especially for children, pregnant women and those with chronic illnesses.
Conclusion
Melatonin supplements can be helpful for certain sleep problems, but the new findings highlight the importance of using them responsibly. Rather than self‑prescribing, individuals should seek medical advice and focus on improving sleep habits. More research is needed to fully understand melatonin’s long‑term effects on heart health.
Sources: ScienceDaily, National Center for Complementary and Integrative Health