“# The leading explanation: melatonin is a marker, not a cause”
The strongest and most widely accepted interpretation is:
Confounding by insomnia and poor health
People using melatonin long-term often have:
- Chronic insomnia
- Circadian disruption
- Depression/anxiety
- Cardiometabolic disease
These conditions independently increase heart failure risk via:
- Sympathetic activation
- Elevated cortisol
- Inflammation
- Hypertension
So melatonin use may simply identify a higher-risk population, rather than cause the risk