Best Supplements for Sleep: One Is Supported, and It Buys You Seven Minutes
Melatonin is the most-studied thing on this list, and in the pooled trials it gets you to sleep about seven minutes faster. When someone went and measured what was actually in the bottles, the contents ran from 83% under the label to 478% over it. [the full verdict]
We have checked 10 of the things sold for sleep, one at a time, reading the trials rather than the packaging.
Exactly one of them is Supported for sleep itself. It is the seven-minute one. Everything else on this page is either unsettled, settled for a different outcome entirely, or did not hold up.
Nothing here is for sale and nothing links to a shop. Every row goes to the verdict it came from, so you can check the working.
| What | Verdict | What we measured |
| Melatonin Seven minutes faster to sleep, pooled. The dose on the bottle is usually far more than the trials used, and often far from what is actually inside. | supported | 7 min faster to sleep, pooled across trials |
| What | Verdict | What we measured |
| Magnesium It is in the top three of almost every sleep list ever written. What the evidence actually settles is that it lowers blood pressure. It does not fix the leg cramps either. | supported | 2.0 mmHg off systolic blood pressure, across 34 double-blind trials |
| What | Verdict | What we measured |
| Tart cherry juice The famous 84-minute result came from eight people. The better evidence on this one is about something else. | preliminary | 8 people the 84-minute result came from |
| Mouth taping The studies excluded anyone with a blocked nose, which is most of the people reaching for tape. | preliminary | 213 patients in the entire literature |
| Blue-light blocking The mechanism is real. The link onward to recovery and gains is not. | preliminary | 1 in 5 studies finding sleep quality decreased, in the cited review |
| Putting the phone down 63 studies agree it travels with bad sleep. Not one can say which direction the arrow points. | preliminary | 63 studies — every one of them observational |
| Ashwagandha Cortisol drops. Whether you feel better is a separate question, and the study that asked both got two different answers. | preliminary | 0.40 p-value for perceived stress — the outcome it is sold on |
| Box breathing It works. So did every other breathing pattern they tested against it. | preliminary | 21 people randomised to box breathing in the only head-to-head trial |
| What | Verdict | What we measured |
| Sleep hygiene, on its own The clinical guideline explicitly tells doctors not to use it as a standalone treatment for insomnia. | unsupported | 1.01 what sleep hygiene adds inside CBT-I. 1.00 is nothing |
| Magnesium glycinate specifically The absorption trial behind “the most bioavailable form” was twelve people with resected bowels, and it came out even. | unsupported | 4 patients the absorption advantage came from |
Established means several independent lines of evidence agree. Supported means good evidence with a caveat worth knowing. Preliminary means real trials exist and are not yet good enough to tell you what the thing does. Unsupported means we looked and the claim was not there.
Nothing on this page reaches Established, and that is worth sitting with. Sleep is among the most-studied things a person can measure, the market for fixing it is enormous, and the best-evidenced product in it moves the number by seven minutes. The gap between how confident the packaging sounds and how confident the evidence is may be wider here than anywhere else we have looked.
The same corpus, asked other ways: for weight loss, where nothing reaches Established either, for muscle growth, for men and for women, for gut health, and for recovery, and for sweeteners, where every claim is a worry and the ratings run backwards.
The four ratings are the same ones used on every verdict here, and we wrote down how we read a study so you can see what earns each one.