The Best Supplements for Sleep — and the One We Don't Sell

What we would actually take, and why:

1. Magnesium Glycinate — the form with a trial on the form, not just the mineral
2. L-Theanine Calm — for the mind that will not stop rather than the body that will not settle
3. Magnesium Complex — if you want one magnesium doing both day and night
4. Melatonin — the one we do not make, and the reason why matters

011. Magnesium glycinate

Most magnesium-and-sleep research studies magnesium generally, then gets applied to whichever form is being sold. That gap closed in 2025. A randomised, placebo-controlled trial gave healthy adults reporting poor sleep 250 mg of elemental magnesium as bisglycinate specifically, and measured insomnia severity over four weeks.¹

The magnesium group improved more than placebo — a drop of 3.9 points on the Insomnia Severity Index versus 2.3 for placebo.¹ We want to be straight about what that means: the authors themselves describe the effect size as small, and the p-value was 0.049, which is a hair inside significance rather than a landslide.

The more interesting finding is buried in the exploratory analysis. Improvement was notably greater in participants whose dietary magnesium intake was low to begin with.¹ That is the pattern across nutrient research generally: repletion helps the depleted, and does much less for everyone else. A broader 2022 systematic review of supplements for sleep reached similarly measured conclusions.²

Glycinate is also the form least likely to send you to the bathroom, which matters when the whole point is not waking up. We compared the forms in why form decides everything.

022. L-theanine

L-theanine is an amino acid found in tea. A 2025 systematic review and meta-analysis pooled the trials on sleep outcomes specifically,³ and separate randomised work has looked at it alongside magnesium in chronically stressed adults, where sleep quality was a secondary endpoint.⁴

The practical distinction we would draw: magnesium is for a body that will not settle, L-theanine is for a mind that will not stop. It does not sedate. It takes the edge off arousal, which is a different mechanism and a different feeling. That is also why it works in the daytime without making you drowsy — we wrote about that pairing in caffeine sharpens, L-theanine smooths.

Ours is 200 mg, the dose used in most of the research, in a single capsule.

033. Magnesium Complex

If you want magnesium for muscle and energy in the day as well as sleep at night, running two bottles is inefficient. Magnesium Complex combines bisglycinate with malate for that reason. If sleep is the only goal, glycinate alone is the cleaner choice. We set out how to pick in choosing by time of day.

044. Melatonin — and why we do not sell it

This is where we differ from most of the category, so it is worth being explicit.

Melatonin is not a sedative. It is a timing signal — the hormone that tells your body what time it is. Used for jet lag or a shifted body clock, it is doing the job it evolved for. Used as a nightly knockout for ordinary poor sleep, it is being asked to do something it does not do, and the disappointment that follows is predictable. We laid the mechanism out in melatonin is a timing signal, not a sedative.

There is also a dosing problem. The amounts sold commercially are frequently many times what the research uses, and combination products stack it with magnesium and B vitamins in ways that make it impossible to tell what did what.⁵

We would rather not sell you something that mostly works for a problem you probably do not have.

05What actually moves the needle more than any of this

Consistent wake time, light in the morning, and a dark cool room outperform every supplement on this page, and they are free. We are aware that is an odd thing for a supplement company to write down. It is also true, and we set out the full protocol in the 7-night wind-down.

If you have addressed those and still want support, the Restful Sleep range is where to start.

06What we can actually show you

The claims above are about nutrients, and the evidence is what it is — modest, and strongest in people who were short to begin with. What we can be definite about is what is in the bottle. Every lot is tested by an independent laboratory for identity, potency, heavy metals and microbials, and the certificate for the lot currently shipping publishes on the product page.

07Frequently asked questions

How long before bed should I take magnesium?

Most trials dose in the evening, typically thirty to sixty minutes before bed. Consistency across weeks matters more than precision on any single night.

How much magnesium is the right amount for sleep?

The 2025 bisglycinate trial used 250 mg of elemental magnesium daily.¹ Check the elemental figure rather than the compound weight — they are not the same number, and labels often show the larger one.

Can I take magnesium and L-theanine together?

Yes. They work through different mechanisms, and they have been studied in combination in stressed adults.⁴

Why does magnesium work for some people and not others?

The best available answer is baseline status. In the bisglycinate trial, improvement was greater in those with lower dietary magnesium intake to start with.¹ If you were not short, there is less to correct.

Is glycinate better than citrate or oxide for sleep?

For sleep specifically, glycinate is the form with a trial on the form, and it is the least likely to cause a laxative effect. Oxide is poorly absorbed and largely does the opposite job.

Should I take melatonin instead?

If your problem is a shifted body clock — jet lag, night shifts — melatonin is the right tool. If your problem is that you cannot get to sleep at a normal hour in your own time zone, it is usually the wrong one.

08References

1. Magnesium bisglycinate supplementation in healthy adults reporting poor sleep: a randomized, placebo-controlled trial. 2025. PMCID: PMC12412596.
2. Chan V, Lo K. Efficacy of dietary supplements on improving sleep quality: a systematic review and meta-analysis. Postgrad Med J. 2022;98(1158):285–293. doi:10.1136/postgradmedj-2020-139319
3. Bulman A, D'Cunha NM, Marx W, Turner M, McKune A, Naumovski N. The effects of L-theanine consumption on sleep outcomes: a systematic review and meta-analysis. Sleep Med Rev. 2025.
4. Pickering G, Noah L, Pereira B, et al. Effect of a combination of magnesium, B vitamins, rhodiola, and green tea (L-theanine) on chronically stressed healthy individuals: a randomized, placebo-controlled study. Nutrients. 2022. PMCID: PMC9102162.
5. Djokic G, Vojvodic P, Korcok D, et al. The effects of magnesium–melatonin–vit B complex supplementation in treatment of insomnia. Open Access Maced J Med Sci. 2019;7(18):3101–3105. doi:10.3889/oamjms.2019.771
6. Dhillon VS, Deo P, Thomas P, Fenech M. Low magnesium in conjunction with high homocysteine and less sleep accelerates telomere attrition in healthy elderly Australians. Int J Mol Sci. 2023;24(2):982. doi:10.3390/ijms24020982

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.