Long-term melatonin use linked to 90% higher heart failure risk
Preliminary research suggests a potential link between long-term melatonin use and an increased risk of heart failure in patients with chronic insomnia. While the study does not prove causation, it raises concerns about the safety of long-term supplement use.
Why it matters
Many people use melatonin as a natural sleep aid, making these findings significant for public health and medical counseling.
Long-term use of melatonin, a widely used sleep supplement, was linked to a higher risk of heart failure, hospitalization for heart failure, and death from any cause among people with chronic insomnia, according to preliminary research presented at the American Heart Association's Scientific Sessions 2025.
The findings do not prove that melatonin itself caused the increased risks. However, they raise new questions about the long-term safety of a supplement that many people view as a harmless or "natural" way to improve sleep.
Melatonin is a hormone made naturally by the pineal gland in the brain. It helps control the body's sleep and wake cycle, also known as the circadian rhythm. Levels of the hormone typically rise when it gets dark and fall during daylight.
Synthetic melatonin is chemically identical to the hormone produced by the body. It is commonly used for insomnia (difficulty falling and/or staying asleep) and jet lag.
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