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 a staple of sleep lists. What the evidence actually settles is that it lowers blood pressure a little, mostly when it is high. It does not stop older adults’ night 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 Sleep is its best-supported claim, on five small trials. Cortisol drops; whether people feel less stressed is contested, and most trials had a company’s money, product or staff. | preliminary | 0.40 p-value for perceived stress in one of four reviews; three found a drop |
| Box breathing Mood lifted a little after each session, as much as with two other breathing patterns. Tried over four weeks of daily life, it brought no clear drop in stress. | preliminary | 21 people in the box-breathing arm of the month-long trial |
| What | Verdict | What we measured |
| Sleep hygiene, on its own The insomnia guideline advises doctors against it as a standalone treatment: the only treatment it advises against. | 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.