What do sleep, breathing, digestion, and your heart rate have in common? They’re all involuntary functions that we usually take for granted, right up until they start to fail.

Insomnia, or difficulty falling asleep, has many causes, the most common of which are stress and poor sleep habits. The latter is easier to manage by making lifestyle changes to promote sleep, such as setting a consistent bedtime, avoiding naps, and limiting screen exposure before bed. Stress, on the other hand, can be much more difficult to deal with, as factors that cause stress are often out of your control. Sleepless nights can quickly spiral into sleep anxiety, a fear of being unable to sleep, which often perpetuates a person's inability to sleep and starts a vicious cycle towards long-term insomnia. Given all these unpleasant experiences, it is unsurprising that those afflicted are quick to seek a short-term and effective solution.

The solution for many people, of course, is melatonin. Melatonin is a sleep aid named after a natural hormone produced in the body to regulate the sleep-wake cycle. The supplements help users to fall asleep by mimicking the hormone and can be used to treat afflictions from simple jet lag to sleep disorders.  A study at Dongzhimen Hospital analyzed the trends in melatonin use from 1999 to 2018 and found that the use of melatonin in US adults more than quintupled within the given timeframe. While this data alone is not medically concerning, it highlights the need for further studies on the long-term safety and efficacy of melatonin, given its increasing popularity.

You may have noticed that melatonin is always referred to as a supplement. This raises an important distinction between the terms “supplement” and “drug.” 

Drugs are tested by the Food and Drug Administration (FDA) and are intended to diagnose and treat disease. Drug manufacturers undergo rigorous clinical trials to demonstrate the safety of their products before they are approved for prescription. 

Supplements, on the other hand, are not regulated by the FDA and are considered safe unless proven otherwise to be unsafe. Additionally, supplements can be purchased over the counter without a prescription, leaving the use and dosage of supplements at the discretion of the user. This allows consumers to use melatonin for purposes beyond its intended use. 

In 2025, the American Heart Association Scientific Session explored the potential connection between long-term melatonin use and heart disease. This discussion arose from a research abstract that studied 5 years of health data and found that individuals with insomnia who used melatonin were more likely to develop an increased risk of heart failure or death, compared to individuals with insomnia who did not use melatonin. Given that melatonin supplements were previously considered virtually harmless, this finding may lead to a re-evaluation of how melatonin is prescribed. 

 It is essential to note that the article that generated these claims is a preliminary study. Additionally, since the research was a review of health records rather than a clinical trial, the study cannot establish a direct cause-and-effect relationship between melatonin use and heart disease. 

Melatonin is being increasingly used as a sleep aid. While the supplement may initially appear as a miracle drug for those facing restless nights, long-term use of melatonin is not encouraged and is still being researched. Aside from the direct possible effects of overusing the supplement, individuals should not solely use melatonin to combat stress-based insomnia. Melatonin is not an official cure for insomnia, and should not be treated as such unless prescribed by a doctor. Stress-based insomnia is your body’s sign that there is an issue in your life that needs addressing. Whatever the conflict, it should ideally be addressed at its core.