Key Highlights
- A new study has found that long-term use of melatonin for sleep aid increases the risk of heart issues.
- The research indicates that those prescribed melatonin for over a year are 89% more likely to develop heart failure and twice as likely to die from any cause compared to non-users.
- Medical researcher Ekenedilichukwu Nnadi warns that this could affect how doctors counsel patients about sleep aids.
- The study’s methodology has limitations, primarily due to reliance on prescription records without direct user surveys.
New Research Raises Concerns About Long-Term Use of Melatonin for Sleep Aid
A recent study presented at the American Heart Association’s Scientific Sessions in November 2025 has raised significant concerns about the long-term use of melatonin as a sleep aid. The research, which analyzed data from over 130,000 adults across multiple countries, revealed that those prescribed melatonin for more than a year faced an increased risk of heart issues.
According to the study, individuals who were prescribed melatonin long-term had an 89% higher risk of developing heart failure over five years compared to non-users. Moreover, they were twice as likely to die from any cause. These findings suggest that further research is necessary to ensure the safety of prolonged melatonin use.
Current Health Recommendations and Melatonin Safety
Melatonin is typically considered safe and well-tolerated for short-term use among non-pregnant adults, usually up to 1-2 months. However, comprehensive research on its effects after this period is limited. The study’s findings challenge the perception of melatonin as a benign chronic therapy.
Medical researcher Ekenedilichukwu Nnadi from SUNY Downstate/Kings County Primary Care in New York stated, “Melatonin supplements may not be as harmless as commonly assumed. If our study is confirmed, this could affect how doctors counsel patients about sleep aids.” This statement highlights the potential impact of the research on medical practice and patient care.
Study Limitations and Future Research
The study has some methodological limitations, particularly due to its reliance on prescription records. Participants were not directly surveyed regarding their melatonin use, which could introduce inaccuracies in the control group’s data. For example, individuals who took melatonin without a prescription in the US might have been included in the non-users group.
Carlos Egea, President of the Spanish Federation of Sleep Medicine Societies and an expert not involved in the study, noted these limitations but still emphasized their importance. “These findings challenge the perception of melatonin as a benign chronic therapy and only highlight the need for a prospective trial with a control group to clarify its safety profile,” he argued.
Despite these limitations, the research is concerning and requires further investigation. The study’s presentation at the American Heart Association’s Scientific Sessions underscores the growing importance of thoroughly examining the long-term effects of commonly used supplements like melatonin.
Broader Implications for Long-Term Supplement Use
The findings from this study have broader implications for long-term use of dietary and nutritional supplements. While many such products are widely available over-the-counter, their safety profiles may not be fully understood or documented. This research encourages both healthcare providers and consumers to approach the use of these supplements with caution.
As melatonin continues to grow in popularity, understanding its potential long-term effects becomes increasingly critical. The upcoming prospective trials mentioned by Egea will likely provide more clarity on the safety and efficacy of prolonged melatonin use for sleep disorders.
