Long-term use of melatonin supplements to support sleep may have negative health effects

 https://newsroom.heart.org/news/long-term-use-of-melatonin-supplements-to-support-sleep-may-have-negative-health-effects

A review of 5 years of health records for more than 130,000 adults with insomnia who had used melatonin for at least a year found they were more likely to be diagnosed with heart failure, require hospitalization for the condition or die from any cause.

The association between melatonin and increased risk of heart failure or death found in this study, which cannot prove a cause-and-effect relationship, raises safety concerns about the use of melatonin, which is widely available, and may warrant more research on melatonin to assess its cardiovascular safety, researchers said.