What do the states mean?+
- Solid: well studied, and it works.
- Half-there: the science is still forming.
- A ghost: almost no real studies.
- Hollow: well studied, and it does not work.
- A cord: the pair itself has been tested together.
- Air: nobody has ever tested this pair.
The full scoring method: How we score
Melatonin benefits: where the science stands
For sleep: yes.
Sleep is what most people take melatonin for, and the strongest evidence says it helps (two combined reviews covering 54 trials). As of August 2026, the verdicts on this page rest on evidence from 151 trials, drawn from the strongest research among the 1,059 papers on PubMed that mention melatonin. Every claim is checked below.
1,059 papers on PubMed · evidence from 151 trials
Claim by claim
- SleepWell studied, and it works. The biggest review covered 31 trials.
- CholesterolThe science is still forming. The best studies disagree.
- EnduranceThe science is still forming. No real difference found so far.
- Energy and fatigueThe science is still forming. Results lean positive, but there is not much yet.
See 1 more scored claim+
- HeartThe science is still forming. Results lean positive, but there is not much yet.
Pairs people ask about
The six sources we read
- 2018Meta-analysis · pools 31 trials · small benefit for sleepsource
- 2022Meta-analysis · pools 23 trials · moderate benefit for sleepsource
- 2024Meta-analysis · pools 19 trials · no clear effect on endurancesource
- 2024Meta-analysis · pools 6 trials · no clear effect on cholesterolsource
- 2025Meta-analysis · pools 63 trials · small benefit for cholesterol; moderate benefit for heartsource
- 2025Meta-analysis · pools 9 trials · small benefit for energy and fatiguesource
Chosen as the strongest evidence out of 1,059 papers on PubMed. Every row links to its paper.
Fair questions
Does melatonin work?+
For sleep, yes. The biggest review covered 31 trials.
Is melatonin safe?+
No caution is recorded on this page. That is not a safety guarantee; the studies we read were not safety trials.
Why only 6 sources, when PubMed lists 1,059?+
The 1,059 is every paper that mentions melatonin in any way: animal studies, blood measurements, papers where it is a side note. The strongest sources are combined reviews, and each one already gathers every trial its authors could find. Our 6 cover 151 trials between them, and every one is linked above. Both counts are measured, not estimated.