Travel & Lifestyle: New Study Says Melatonin May Be Harming Your Heart

Is it time to rethink your melatonin habit? New research says potentially, but many doctors aren’t so sure.

In a new, not yet peer-reviewed report published by the American Heart Association, researchers looked at five years of medical records from 130,828 people and found that those who were prescribed and took melatonin for 12 months or more had a 90% higher chance of heart failure when compared to those who didn’t take the supplement.

Researchers also found that melatonin users were at higher risk of being hospitalized for heart failure and dying of any cause.

Heart failure is a condition in which the heart isn’t able to pump effectively and can’t provide the body with enough oxygen. It can be managed with medication, along with lifestyle changes (such as diet and exercise), but can also lead to heartbeat issues, liver damage and even death.

“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,” lead study author Dr. Ekenedilichukwu Nnadi said in a press release.

Melatonin is a naturally produced hormone in our body that helps manage our body’s sleep-wake cycle. It’s also available over-the-counter and via prescription in the United States.

“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,” Nnadi said in the press release.

It’s worth noting that this study has limitations. Since researchers relied on electronic medical records, only prescribed melatonin use was tracked, which means people in the control group could have been taking over-the-counter melatonin regularly without the researchers’ knowledge. Moreover, the melatonin dose for each participant is unknown.

Experts warn that correlation does not equal causation. This research doesn’t mean that taking a melatonin supplement for an extended period of time will cause heart failure. In fact, the need for sleep assistance could be a sign of other health problems that are tied to heart failure instead.

Nnadi told NBC News that “insomnia can increase blood pressure, stress hormones and inflammation.”

High blood pressure is a heart failure risk factor, and high stress levels can also contribute to the likelihood of developing the condition. People in the study who treated their insomnia with melatonin could have these underlying, insomnia-related conditions (that aren’t tied to melatonin use) that then put them at heightened risk of heart failure.

Other studies haven’t shown this melatonin-heart failure connection.

Joyce Oen-Hsiao, an associate professor of cardiovascular medicine at Yale School of Medicine, told the Washington Post that this report is “the only one that is saying that melatonin can cause heart failure.” Oen-Hsiao is not affiliated with the research.

“Right now, we don’t have enough information to blanketly say all people should stop using melatonin,” Oen-Hsiao told the Washington Post.

That isn’t to say you shouldn’t talk to your doctor about the potential risks. More research is needed to determine what risks are associated with melatonin, but just because it’s “natural” doesn’t mean it’s without consequences.

Not getting enough sleep or enough quality sleep can not only lead to high blood pressure, inflammation and higher stress, but is also linked to cardiovascular disease, plaque build-up in the arteries and other heart issues.

Adults should aim for seven to nine hours of sleep each night, Dr. Indira Gurubhagavatula, a professor of medicine in the division of Sleep Medicine at the University of Pennsylvania, previously told HuffPost.

Keeping your bedroom cool and dark, and staying off your phone in bed can help make drifting off to sleep a little easier. Limiting caffeine and exercising during the day can also help with sleep regulation.

However, for those with insomnia, this sleep advice may be of little benefit. Instead, a sleep specialist can help determine the necessary steps to help you get proper rest, while also evaluating for any underlying sleep conditions (such as sleep apnea) that may be preventing you from getting high-quality sleep.

Heart disease is the number one killer of adults in the United States. While following a healthy diet and exercising are well-known ways to lower your risk, prioritizing good sleep is, too — without the long-term help of melatonin.