Animal studies suggest that humans might need 100 to 200 milligrams of melatonin daily to get its protective and anti-inflammatory benefits, which is much higher than the 2 to 10 milligrams usually tested in heart studies. This big difference in dosage might be why past heart research hasn't shown clear results.

When you take melatonin pills, your body only absorbs about 15% of the dose into your bloodstream because most of it gets broken down before it can circulate. This means oral supplements deliver much less active melatonin to your system compared to an injection.

People process melatonin very differently, even when taking the exact same 10-milligram dose. Factors like your genes, metabolism, and body chemistry cause these wide differences, which is why it's so hard to create one-size-fits-all dosage recommendations.

Taking 10 milligrams or more of melatonin every day for at least three months may help lower your body's overall inflammation levels. This happens because the supplement might block a specific cellular switch that normally triggers inflammatory chemicals like IL-6 and TNF-alpha.

Taking a higher dose of melatonin might help more of the supplement actually get into your bloodstream. This happens because larger amounts can overwhelm the liver's natural breakdown process, making the supplement more effective than standard low doses.

This means that no matter whether you take melatonin as a pill or get it through an IV, your body clears it out at the exact same speed once it's in your blood. The way you initially get the supplement into your system doesn't change how long it stays in your body.