Melatonin and Your Heart: New Research Raises Alarming Concerns

If you’ve been reaching for melatonin gummies night after night to coax yourself into dreamland, you might want to pause and read this.

A team of researchers affiliated with the American Heart Association dug into a massive database of anonymized health records and uncovered a startling pattern: people who used melatonin regularly for at least 12 months faced roughly a 90 % higher odds of being diagnosed with congestive heart failure over the next five years.

Now, before you fling your supplement bottle into the trash, there are a few important nuances. This wasn’t a randomized clinical trial where participants were assigned melatonin or a placebo. Instead, the investigators identified two cohorts among chronic insomniacs—those who reported using melatonin for a year or more and those who didn’t take the hormone at all.

The numbers paint a worrisome picture. In the melatonin‑using group, 4.6 % eventually developed heart failure, compared with just 2.7 % of the non‑users. And it gets worse: a secondary look at hospital records showed that melatonin takers were about 3.5 times more likely to be admitted for heart‑failure complications—19 % versus 6.6 %.

“Melatonin supplements are widely thought of as a safe and ‘natural’ option to support better sleep, so it was striking to see such consistent and significant increases in serious health outcomes, even after balancing for many other risk factors,” said Ekenedilichukwu Nnadi, the study’s lead author and chief resident in internal medicine at SUNY Brooklyn.

While the findings are far from definitive—observational data can’t prove cause and effect—they do raise a red flag. Nnadi warned that “melatonin supplements may not be as harmless as commonly assumed,” and that clinicians may need to rethink how they advise patients seeking over‑the‑counter sleep aids.

What does this mean for you? If you’re relying on melatonin nightly, consider discussing alternative sleep strategies with your doctor. Simple changes—like limiting screen time before bed, establishing a consistent bedtime routine, or exploring cognitive‑behavioral therapy for insomnia—might reduce the need for a supplement altogether.

Bottom line: the sleep‑helping hormone that many of us regard as benign could carry hidden cardiovascular risks when used long‑term. More rigorous studies are needed, but until then, a cautious approach seems prudent.