[fnordpiglet]

That’s sort of a shocking statement. The primary use case is to feel drowsy and fall asleep. It’s the hormone that induces drowsiness that is readily absorbed by the gut unchanged and impacts systemic levels of said hormone. We not only know it’s effective by like billions of humans trying it trillions of times, we know it’s effective by like nearly every vertebrate animal in biochemical processes we kinda understand sleeping every single day for all of lifes history.

What evidence is lacking exactly?

[glitchc]

We used to think cocaine was an excellent cure for depression and not addictive at all. It's naturally occurring, millions of people took it.

https://www.narconon.org/drug-information/cocaine-circa-1860...

Anecdotal evidence is not a substitute for pharmacology research, controlled medical trials.

[fnordpiglet]

Cocaine isn’t naturally occurring in every vertebrate animal as the hormone responsible for not making you depressed. Plutonium is naturally occurring as well, but it’s not a part of the fundamental biology of all animals. Melatonin is as naturally occurring in animals as blood and its purpose we use it for as a supplement is precisely what it does in the body. It’s nudging the natural levels slightly higher to induce exactly what it does and we desire from it. There’s literally no debate anywhere in any context as to whether it does what it says on the tin, because it literally is the thing that does the thing on the tin.

But, you know, sure. Why not. Of course people did these studies because with positive results you’ll get published and it’s a bit of a softball, since it’s like, exactly what must be the result given the situation:

https://pubmed.ncbi.nlm.nih.gov/33417003/

Results: Of 2642 papers, 23 RCTs met inclusion criteria. Our results indicated that melatonin had significant effect on sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI) (WMD: - 1.24; 95% CI - 1.77, - 0.71, p = 0.000).

Conclusion: We found that the treatment with exogenous melatonin has positive effects on sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI) in adult.

https://pubmed.ncbi.nlm.nih.gov/31982807/

Conclusions: Melatonin was an effective and tolerable drug in the short-term treatment of sleep onset insomnia in children and adolescents.

Etc

There’s no controversy whether it works or not. The only controversy is on chronic supplementation, which is entirely fair.

[glitchc]

Certainly, if there's medical research indicating that melatonin is safe, all the better. As long as we're following the scientific process to generate a reproducible body of knowledge supporting the assertion that melatonin is safe.

[fnordpiglet]

Yeah. My point was though beyond random controlled trials we actually understand melatonin at a really fundamental level, and it’s not just that we understand it, but we identified it in as far as I can tell all vertebrates. That’s stronger than RCT’s. It’s like questioning we know whether blood infusions are actually effective at treating blood loss.