Melatonin

Q: How much melatonin should you take for sleep?

Most positive sleep studies land somewhere between **0.5 and 5 mg** nightly, even though the full research range runs much wider. Bigger doses show up in papers, but the evidence doesn't tell a simple "more is better" story.

Q: Does melatonin actually work for jet lag?

Yes—jet lag is one of melatonin's clearest use cases. Reviews show it helps your body clock line up with local time faster when you take it around the new bedtime after crossing time zones.

Q: Why does melatonin help me fall asleep but not keep me asleep?

That pattern fits the data. Melatonin's main job is sending a "night has started" signal to your body clock, so studies more consistently improve sleep onset than overnight wake-ups.

Q: How long before bed should you take melatonin?

Think in terms of the bedtime you want to hit, not the middle of the night after you've already been awake for hours. Trials usually line melatonin up with the target sleep window or the destination bedtime in jet lag because it shifts timing more than it acts like an instant sedative.

Q: Can you take melatonin every night?

Many studies use melatonin nightly for days to weeks, and some continue much longer. It makes the most sense when you use it to solve an actual timing problem—like trouble falling asleep at the right time or travel-related clock mismatch.

Abstract

Evidence summary

Proven benefit

Melatonin provides proven benefit for falling asleep faster and easing jet lag in adults with sleep-timing problems, while benefits are smaller for total sleep time and nighttime awakenings.

Across 28 studies (n=3,962), melatonin shortened time to fall asleep.2
Melatonin evidence spans 101 papers and 203 outcomes, strongest for sleep timing and jet lag.
Benefits are smaller for total sleep time and inconsistent for nighttime awakenings.2