Melatonin Heart Risk: What the Sleep Aid Study Found

The gummy you take every night to fall asleep might deserve a second look. A Melatonin Heart Risk signal from new research links taking the popular sleep aid for more than a year to a meaningfully higher chance of heart failure and death over five years, and regulators are starting to take the possibility seriously.

The analysis looked at the electronic health records of more than one hundred thirty thousand adults with insomnia across several countries. Those who were prescribed melatonin for longer than a year faced a heart failure risk nearly ninety percent higher than matched patients who were not, and they were roughly twice as likely to die from any cause within five years, according to ScienceAlert's report on the findings. Hospitalizations told an even starker story: long-term users landed in the hospital for heart failure at about nineteen in a hundred, compared with roughly seven in a hundred among non-users.

The work was presented in late 2025 at the American Heart Association's Scientific Sessions by medical scientist Ekenedilichukwu Nnadi of SUNY Downstate in New York. Melatonin ranks as the fourth most popular natural product taken by adults in the United States, which is what makes the numbers hard to ignore: about five in a hundred long-term users developed heart failure over the study window, versus fewer than three in a hundred of those who did not take it. "Melatonin supplements are widely thought of as a safe and 'natural' option to support better sleep," Nnadi said. "So it was striking to see such consistent and significant increases in serious health outcomes, even after balancing for many other risk factors."

A safety signal, not a verdict

There are important reasons not to panic. The study has not been peer-reviewed, and it does not prove that melatonin causes heart damage. The researchers did not survey people about their supplement habits; they used prescription records to estimate who was taking it. That matters enormously for American shoppers, where melatonin sits on store shelves and most users buy it without a prescription. Those over-the-counter users were counted as non-users, which muddies the comparison from the start.

Critics have been blunt about the design. Carlos Egea, who leads the Spanish Federation of Sleep Medicine Societies and was not involved in the study, flagged the prescription-record caveat while saying the associations should still be taken seriously. Harneet Walia, the medical director of sleep medicine at Baptist Health's cardiac institute in Miami, pointed to the same blind spot: electronic records miss the huge group of Americans taking the supplement off the shelf. One independent analysis noted the study's melatonin group was not made up of typical healthy supplement users at all, but people whose use showed up in medical records, meaning they were sicker and more medicated to begin with.

Even so, the signal has crossed into regulator territory. In April 2026, Saudi Arabia's drug regulator issued a formal safety signal on melatonin and heart failure after reviewing global case reports alongside the study's findings, concluding the evidence so far is "suggestive for causal association." That is not a ban or a new warning label, but it is the first official body saying the possibility cannot be waved away. Nnadi himself expressed surprise that physicians prescribe melatonin for insomnia for more than a year at a stretch, since the substance is not indicated for chronic, unmonitored use.

Why this hits close to home for Gen Z

Melatonin is not an abstract risk for young people. A recent campus survey found that nearly a third of students had used melatonin or another sleep supplement in the past year, while most had never tried the free fix of a consistent bedtime, as covered in GenZ NewZ's look at the body-clock knowledge gap. The supplement sits at the intersection of two Gen Z epidemics: terrible sleep and total trust in anything labeled natural. The researchers stress that short-term use, meaning roughly a month or two, remains generally considered safe, and none of this is a reason to flush your gummies in a panic.

What the Melatonin Heart Risk data really argues for is a check-in. If melatonin has quietly become a permanent part of your nightly routine, that is worth a conversation with a clinician about dose, duration, and whether something underneath the insomnia deserves attention. The biggest lesson of the study may be about research itself: correlation is not causation, a prescription database is not the same as a pharmacy shelf, and the Melatonin Heart Risk story will only be settled when someone runs the careful long-term trial this data cannot provide.

Until then, the boring advice wins. New research on teen sleep shows late-night phone use wrecks rest more than most people admit, and no gummy fixes a glowing screen at two in the morning. Sleep hygiene is unglamorous, but unlike a nightly supplement habit, it has never triggered a safety signal.

Sources: ScienceAlert, Alchemist