The average melatonin supplement sold in the US contains 5-10mg of melatonin. The dose shown in research to be effective for most sleep issues? 0.5mg.
That’s a 10-20x overdose in most products. And it matters — taking too much melatonin can actually disrupt your natural melatonin production over time.
What Melatonin Actually Does
Melatonin is not a sedative. It’s a timing signal. Your brain produces it naturally in response to darkness, signaling to your body that it’s time to prepare for sleep. It doesn’t knock you out — it shifts your biological clock.
This is why melatonin is most effective for circadian rhythm disruption: jet lag, shift work, delayed sleep phase syndrome. It’s less effective as a general sleep aid for people who just struggle to fall asleep at a normal time.
Why the Dose Matters So Much
A landmark study published in the Journal of Clinical Endocrinology and Metabolism found that doses as low as 0.3mg were effective for shifting sleep timing. Higher doses don’t produce proportionally better results — they just flood your melatonin receptors and potentially suppress your body’s natural production.
The 5-10mg products dominating US pharmacy shelves are a product of supplement industry marketing, not science.
What to Look For
Dose: 0.5-1mg for general sleep support. Up to 3mg for jet lag or significant circadian disruption. Nothing higher is necessary for most people.
Timing: 30-60 minutes before your target bedtime.
Form: Standard tablets or capsules work fine. Sublingual (under the tongue) forms absorb faster, which can be useful if you need quicker onset.
My Recommendation
For most people: a 1mg melatonin supplement taken 45 minutes before bed. Many brands sell this dose — look for it specifically. Avoid the 5mg and 10mg options.
For jet lag: 0.5-1mg taken at local bedtime for 3-5 nights after crossing multiple time zones. This is melatonin’s strongest evidence base.
One Important Note
Melatonin is a band-aid, not a solution. If you’re relying on it every night, the underlying issue — poor sleep hygiene, anxiety, light exposure, inconsistent schedule — is worth addressing. Melatonin is most valuable as a short-term tool and for specific situations like travel.