Livestack evidence summary — education, not medical advice. https://livestack.us
Sleep
Also in the library: Ingredients · Goals · Evidence · Learn
How sleep timing actually works
Sleep runs on two systems: a circadian clock that decides when your body expects night, and sleep pressure — adenosine building the longer you are awake. Falling asleep on time requires both to line up, and arousal from stress, late caffeine, or bright light can override either one.
Supplements act on narrow parts of that machinery. Melatonin delivers the clock’s night signal on your schedule; magnesium and glycine nudge the winding-down side — GABA activity and core body temperature. None of them sedate you, and none outrank the basics: a consistent schedule, a dark room, and caffeine kept to the morning.
Melatonin is a timing signal, not a sedative. Across 19 trials it shortened time to fall asleep by about 7 minutes and added about 8 minutes of total sleep; nine of ten jet-lag trials favored it after flights crossing five or more time zones. Support for staying asleep through the night is weaker. A dose-ranging crossover found 0.3 mg matched 3 mg for sleep efficiency, with more next-day carryover at the higher dose — which is why retail 5–10 mg bottles are the wrong default.
Caffeine works the other direction: 400 mg taken even 6 hours before bed cut measured sleep by over an hour. Ashwagandha’s sleep pairing rides on the stress effect. Magnesium helped most in older adults whose intake already ran low, and the pooled sleep signal is small. Glycine at 3 g is a handful of small trials from one research group. The list below is ranked by evidence grade, caveats attached.
What this page is
This hub is a reading of the catalog for sleep: the pairings we store at grade C or better, ranked, with the records attached. It is not a store, not a coach, and not a protocol. We do not sell a sleep stack, and we do not write any of these ingredients as if they will make you sleep.
Medications change the list. Melatonin is left out alongside benzodiazepines and prescription sleep medication; ashwagandha is left out with SSRIs. Those rules live on the interactions page and in the stack builder. This is education — bring a stack to your doctor or pharmacist before changing anything.
How grades work on this hub
Melatonin is the only A pairing here: more than one independent human meta-analysis pointing the same way. Magnesium glycinate and ashwagandha sit at B — real trials, real caveats (small samples; a concentrated research network). Glycine and L-theanine are C: people were studied, but the trials are small, and the glycine record comes from one group.
A letter grades the pairing, not a bottle and not a person. Grade D never appears on this list. The same ingredient can carry a different letter on another hub — ashwagandha is B for sleep because the sleep trials are thinner than the stress ones. The scale lives on the grade explainer; the records themselves are in the evidence index.
Ranked by evidence
- Melatonin 0.5–1 mg, 30–60 minutes before bed; raise only if a week at the low dose does nothing
- Magnesium glycinate 200–400 mg elemental in the evening; most useful when dietary intake runs low
- Ashwagandha 300–600 mg root extract in the evening; sleep effect rides on the stress effect
- Glycine 3 g powder 30–60 minutes before bed; evidence is small-trial only
- L-theanine 200 mg in the evening; calm-without-sedation profile, weak direct sleep data
Grades are per goal–ingredient pairing, hand-assigned from the evidence records linked below each name. Browse all records. Ingredients without a monograph link have a page on the way.
What does not work (yet)
The ranked list is only what the goal–ingredient map stores at grade C or better. Popular sleep products with no pairing here — or that sit outside the dietary-supplement category — do not appear because they sell. Grade D never enters a recommendation.
- Melatonin at retail-high doses (5–10 mg). Dose-ranging data show low doses matching high ones for sleep efficiency, with less next-day carryover. More is just more grogginess. See the monograph
- Magnesium oxide. Poorly absorbed — mostly a laxative form. The sleep trials used better-absorbed forms in people whose intake ran low. See the monograph
- Caffeine within 6 hours of bed. 400 mg even 6 hours before bed cut measured sleep by over an hour. Late caffeine works against evening melatonin signaling.
- Melatonin as a stay-asleep sedative. Evidence is clearest for falling asleep sooner and for shifting timing. Support for staying asleep through the night is thinner, including for extended-release forms. See the monograph
- Glycine as a first-line pick. The 3 g trials are small and from one research group. Promising, consistent, unreplicated — a C, not a foundation. See the monograph
- Peptides and NMN. Neither has a sleep pairing in our catalog. They stay editorial: no doses, no offers. Read the editorial
Build a stack for this goal
The list above is the general case. Your medications, current stack, budget, and other goals change it — sometimes a lot. The builder applies those constraints and shows what it left out.