The CDC estimates that roughly a third of US adults don't get the sleep they need on a regular basis.1 The supplement industry's response has mostly been to sell "sleep blends" — five or six ingredients under one undisclosed number. Here's what actually has trial evidence behind it, separated from what's just packaging.
Light exposure and timing, not a pill, is the strongest lever
The single best-evidenced input into sleep quality isn't a supplement at all — it's light. Reviews of circadian research consistently find that bright light exposure earlier in the day and reduced light (particularly blue-spectrum light) in the hours before bed measurably shift sleep timing and quality, by directly influencing the body's circadian pacemaker.2 Consistency of sleep and wake times matters as much as any single ingredient does. This isn't a satisfying answer if you're looking for something to buy, but it's the most reliably evidenced one.
Melatonin: real evidence, and an honest gap in our own range
Melatonin is one of the few sleep ingredients with genuinely strong trial support. A 2024 dose-response meta-analysis of randomized controlled trials found melatonin progressively reduces the time it takes to fall asleep, with the effect peaking around a 4mg dose — and, notably, found that taking it roughly 3 hours before the target bedtime outperformed the more common practice of taking a smaller dose 30 minutes before bed.3
We don't currently sell a standalone melatonin product. Not because the evidence isn't there — it clearly is — but because we haven't yet found a clean, single-ingredient melatonin SKU from a supplier that meets our own sourcing bar; every option we've reviewed so far bundles it into a multi-ingredient blend, which fails our no-blends rule on principle even when melatonin itself would pass on evidence. We're actively tracking this and would rather tell you that plainly than quietly stay silent on it.
Magnesium's more modest, real role
Magnesium is heavily marketed for sleep. The honest read: a meta-analysis of three trials in older adults found it reduced time to fall asleep by around 17 minutes versus placebo — real, but modest, and the authors themselves rated the evidence limited.4 We cover this in more depth in our complete magnesium guide.
Bottom line
The best-evidenced sleep interventions, in order of how strong the evidence actually is: consistent light exposure and sleep timing, properly dosed and timed melatonin (which we don't sell yet, for sourcing reasons, not evidence reasons), and a modest assist from magnesium if you're running low. None of that requires a six-ingredient blend.
This article is for general information and is not medical advice. Supplements are not intended to diagnose, treat, cure or prevent any disease.
References
- CDC: 1 in 3 adults don't get enough sleep. cdc.gov
- Recommendations for daytime, evening, and nighttime indoor light exposure to best support physiology, sleep, and wakefulness in healthy adults. PLOS Biology. journals.plos.org
- Optimizing the Time and Dose of Melatonin as a Sleep-Promoting Drug: Systematic Review of RCTs and Dose-Response Meta-Analysis. Journal of Pineal Research, 2024. pubmed.ncbi.nlm.nih.gov
- Oral magnesium supplementation for insomnia in older adults: systematic review & meta-analysis. ncbi.nlm.nih.gov
Proco Magnesium Glycinate is dosed at 275mg elemental magnesium, third-party tested every batch. Shop Magnesium →