Melatonin – Supplement Friend or Foe?

Melatonin – Supplement Friend or Foe?

If you pay attention to health headlines, you’ve likely come across media coverage of a study that suggested an association between long-term melatonin use and increased risk of heart failure—bad news indeed for the ~20% of U.S. adults who don’t get enough sleep¹ and use melatonin as a natural aid.

The short-term safety of melatonin is widely accepted, and multiple clinical studies indicate that low-dose, short-term supplementation is safe for healthy adults when used as directed. It is not habit forming, and unlike synthetic aids, does not cause a “hangover” the next day. That said, long-term studies have been lacking.

Enter the recent presentation of an abstract to the American Heart Association’s Scientific Sessions 2025. Notably, what was presented was not a full, peer-reviewed study but an abstract (the introductory summary), meaning the findings are only preliminary and not necessarily cause to ring the alarm bell.

There have been numerous responses as lay media outlets have spread fear far and wide across social media. In response, The Council for Responsible Nutrition (CRN), among others, has issued the following statement:

“CRN urges all stakeholders to interpret these preliminary findings with caution and context. As the American Heart Association itself notes, this research represents early, non–peer-reviewed data that cannot establish cause and effect. Chronic insomnia—a condition shared by all study participants—may itself be a contributing factor to heart health outcomes, raising more questions than answers.”²

The study population was limited to those with chronic insomnia, and insomnia itself is linked to cardiovascular health. Therefore, we can’t conclude that melatonin use in healthy adults results in cardiovascular events.

Moreover, the study is observational, does not provide the dose used, and lacks data on insomnia severity and several other parameters that may distort the findings. As The Washington Post correctly summarized, the results “show association, not causation,” and experts agree that “further research is needed before drawing conclusions.”³

The observational data presented at AHA do not alter the safety profile of melatonin when used as directed for occasional sleep issues. According to the CRN, no single study—especially a preliminary abstract—should spur alarmist headlines.

To complicate matters further, but also to alleviate panic, a January 2025 meta-analysis (meaning they looked at several studies) examining circadian rhythm and melatonin in heart failure found that people with lower levels of melatonin had worse prognoses.⁴

Because of its circadian rhythm effects, melatonin has been studied in relation to mood disorders, seasonal affective disorder, neuroprotection, neonatal health, and sexual maturation, and protection against the oxidative stress that contributes to neurodegenerative diseases such as Alzheimer’s.⁵

What is Melatonin and How Can I Use It Safely?

Melatonin is a hormone that helps regulate your circadian rhythm (your bodily clock that signals the wake-sleep cycle). Taking anything, even natural compounds like herbs or hormones, is probably not something to do indefinitely. In the case of melatonin, people might be attacking their sleep issues from the wrong angle. For example, there is a difference between someone who gets into bed, suddenly feels anxious and wide awake, and doesn’t fall asleep for hours versus someone who’s asleep before their head hits the pillow but wakes up at 2 am. There are many natural compounds that can help with sleep, and they address these different scenarios.

The bottom line is that if you have to take something every night to induce the natural and essential bodily function of sleep, you need to examine the root cause. In the first example, that person may have a cortisol spike at night driven by chronic stress. The second person might have woken up by a need to visit the bathroom, which could be due to a variety of factors.

According to the Sleep Foundation, dosages of 0.5 to 1 milligram may be just as effective as higher doses. Children are especially sensitive, as are adults with liver and other medical issues.⁶ Always consult with your doctor and take the lowest dose possible of anything to achieve the desired effect.

Key Takeaway: Melatonin isn’t “bad” and may have other benefits. But nothing is risk-free. Check the evidence, talk to your healthcare provider, and don’t panic—it does not promote sound sleep.