It is a scenario played out nightly in countless bedrooms: popping a chewable, berry-flavoured gummy right before turning off the lights. For a while now, melatonin has been the internet’s favourite bedtime ritual — a simple trick to get some shut-eye. But a new study linking long-term use to heart issues has left many staring at their nightstands in panic. Also read | How much melatonin should one take as sleeping aid?
Is your nightly gummy actually dangerous, or is social media overreacting? Here is what triggered the online chaos, and what a cardiologist with over 30 years of experience says you should actually do.
What spurred the panic
On August 29, Parmita Mishra, founder and CEO of the biotech startup Precigenetics, sparked debate on X (formerly Twitter) when she questioned the safety of everyday melatonin habits: “Do you take melatonin every night? Have any of you seen this wild American Heart Association study?”
She highlighted statistics from the study — including a roughly doubled death rate over five years, a 90 per cent increase in new heart failure, and 3.5 times more hospitalisations for those using melatonin long-term. However, she urged her people to look closer at the fine print before tossing their bottles out.
Parmita said, “My analysis: They didn’t record doses. Melatonin is OTC in the US. Nobody tracks how much anyone actually takes. gummies = 5-10 mg dose that recreates your body’s natural nighttime = ~ 0.3mg. When labs test bottles, the actual content ranges from a fraction of the label to several times it. This is wild. Nuance before you throw your gummies out: this is health records, not a trial. Everyone in it had insomnia, and the melatonin group medicated nightly for a year+, meaning their sleep was probably worse to begin with. Chronic bad sleep ITSELF => heart failure risk!”
What the study actually found
Her post left many social media users overwhelmed, with one admitting, “I’m getting so confused about melatonin.” To clear up the confusion, HT Lifestyle reached out to Dr Rajiv Mehrotra, director of clinical and preventive cardiology at Medanta, Noida.
“Melatonin is commonly used to help with sleep,” he said, adding, “Since melatonin is a hormone naturally produced by the body, many people assume that taking it as a supplement regularly is completely safe. However, a recent study presented at the American Heart Association’s Scientific Sessions 2025 has raised questions about the long-term use of melatonin among people with insomnia.”
The research reviewed health records for ‘130,828 adults with insomnia:
⦿ 65,414 people took melatonin regularly for at least 12 months.
⦿ 65,414 people had insomnia but did not use recorded melatonin (the comparison group).
⦿ Anyone with pre-existing heart failure or prescriptions for other sleep drugs was excluded.
“Over a five-year follow-up period, the researchers found that 4.6 percent of people with long-term melatonin use developed heart failure, compared with 2.7 percent of those in the comparison group,” Dr Mehrotra noted. Also read | Taking melatonin for regular sleep support? Safety concerns, common effects, and expert advice you need to know
“This was reported as about an 89 percent higher relative risk. The researchers also looked at other outcomes. Heart-failure hospitalisation occurred in 19 percent of the melatonin group compared with 6.6 percent of the comparison group, while death from any cause occurred in 7.8 percent compared with 4.3 percent. A separate analysis using a stricter definition of melatonin exposure also found a similar association with heart failure,” he added.
Does melatonin cause heart failure?
The short answer: No. The study proves an association, not a direct cause, Dr Mehrotra said. He explained, “No. This study cannot establish that melatonin causes heart failure. This was an observational study based on electronic health records. The researchers observed that long-term melatonin use and these health outcomes occurred together more often; they did not conduct a randomised clinical trial that could determine whether melatonin itself caused the increased risk.”
According to Dr Mehrotra, several key factors explain why you shouldn’t panic:
⦿ Sleeplessness itself harms the heart: people who take melatonin nightly for a year usually suffer from severe, chronic insomnia. Long-term sleep deprivation is already a known risk factor for cardiovascular disease.
⦿ Data limitations: over-the-counter supplements are rarely accurately recorded in medical records, so dose and frequency weren’t strictly controlled.
⦿ Not yet peer-reviewed: the findings were presented as a preliminary abstract, meaning full medical journals have not completed peer review yet.
Should you stop taking melatonin?
If you rely on a gummy to deal with occasional jet lag, you are likely in the clear. But if you have been taking it every single night for months or years, it might be time to re-evaluate.
“Based on this study alone, people should not assume that they need to stop melatonin immediately,” Dr Mehrotra advised, adding, “The study does not show that occasional melatonin use causes heart failure, nor does it establish that every person taking melatonin long term will develop a heart problem. However, the findings do give us a reason to be more cautious about long-term, regular use, particularly because long-term cardiovascular safety data are limited.”
Dr Mehrotra shared that there is no magical dosage threshold where the supplement suddenly turns harmful: “There is no evidence from this study to suggest that people should change to a particular dose or that there is a specific number of days or months after which melatonin becomes dangerous. The study did not establish a safe or unsafe dose or duration. Instead, people who are using melatonin regularly should consider why they need it.”
He noted that official guidelines from the National Centre for Complementary and Integrative Health (NCCIH) actually recommend against using melatonin for chronic insomnia, favouring treatments like cognitive behavioural therapy for insomnia (CBT-I) instead. Also read | Cardiologist with 30 years of experience explains how prolonged and high dose melatonin use impacts the heart
What to keep in mind
Before grabbing your next bottle, remember that supplements act like medicine inside your body. “Melatonin can interact with medicines,” Dr Mehrotra highlighted. “NCCIH specifically advises people taking medicines to consult their healthcare provider before using melatonin and highlights the need for medical supervision for people taking blood-thinning medicines or those with epilepsy. People who are pregnant or breastfeeding should also speak with a healthcare professional before using melatonin because there is limited information about its safety in these situations,” he added.
The new findings offered a gentle wake-up call, not a reason to throw out your sleep routine in horror, Dr Mehrotra shared as he summarised: “The new study is important because it raises a question about the long-term cardiovascular safety of melatonin, but it does not prove that melatonin causes heart failure.”
“For someone who takes melatonin occasionally, these findings should not be a reason to panic. For someone taking it every night for months or years, however, it is worth discussing whether continued use is appropriate and whether the underlying sleep problem needs to be evaluated. The most accurate message at this point is therefore one of caution rather than alarm,” he concluded.
About the expert
Dr Rajiv Mehrotra is director, clinical and preventive cardiology at Medanta, Noida, with over 30 years of experience in invasive and non-invasive cardiology and critical cardiac care.
Note to readers: This report is based on user-generated content from social media. HT.com has not independently verified the claims and does not endorse them.
This article is for informational purposes only and not a substitute for professional medical advice.
