Most supplement brands hide their dosing behind "proprietary blends." It's the polite way of saying "we don't have to tell you how little is in there."
Moon Milk doesn't have a proprietary blend. It has a sleep stack.
Four ingredients, dosed at study levels, disclosed to the milligram, chosen because they each support a different mechanism your body already uses to fall and stay asleep.
This is what's in it, why it's there, and what each one does.
The frame: support, don't override
Every ingredient in the sleep stack had to clear two filters:
- Does it support a mechanism the body already uses, rather than imitate one with an exogenous compound?
- Does it support the rebuild — the muscle protein synthesis, the deep-sleep architecture, the parasympathetic dominance — that happens during the overnight recovery window?
Magnesium, glycine, L-theanine, and apigenin all clear both filters. Melatonin doesn't, which is why we left it out (read: Why Moon Milk Has Zero Melatonin).
Each ingredient solves a different problem. Stacked, they cover the four pillars of sleep onset and depth: nervous system state, body temperature, mental quietness, and GABA tone.
1. Glycine — 3 g
What it does
Glycine is the simplest amino acid in the body and one of the most under-used sleep tools in the supplement world. Three grams before bed:
- Drops core body temperature by roughly 0.3°C — the same thermal cue your brain uses to initiate deep sleep
- Shortens sleep latency (time to fall asleep)
- Increases time spent in slow-wave sleep
- Improves daytime alertness the next day
The mechanism
Two pathways. First, glycine causes peripheral vasodilation — your blood vessels at the skin surface widen, releasing heat, dropping your core temperature. That core-temp drop is a master regulator of slow-wave sleep onset. Second, glycine acts on NMDA receptors in the suprachiasmatic nucleus (your brain's master clock), supporting the circadian transition from wakefulness to sleep.
The study
Yamadera et al. (2007) gave 19 volunteers with poor sleep quality 3 g of glycine 30 minutes before bed. The result: improved subjective sleep quality, decreased sleep latency, less daytime sleepiness, and improved alertness — all in a placebo-controlled crossover design.
Why we use 3 g
That's the dose the study used. Most consumer glycine products either don't disclose the dose or use 500 mg — six times below the studied amount. We match the literature.
Bonus benefit: glycine is a building block of collagen. So you're getting connective-tissue support overnight as a side effect.
2. Magnesium bisglycinate — 200 mg
What it does
Magnesium activates the parasympathetic nervous system — the "rest and digest" mode that has to be dominant for deep sleep to occur. About 50% of Americans don't hit the magnesium RDA from diet alone, which is part of why "wired but tired" is the modern default state.
The mechanism
Magnesium is a cofactor for GABA receptor binding. GABA is the brain's primary inhibitory neurotransmitter — the brake pedal. When magnesium is low, GABA receptors don't bind well, and the brake doesn't work right. Top that off with magnesium's role in melatonin synthesis (it's needed for the enzyme that converts serotonin to melatonin) and you get a clean three-pathway support: parasympathetic activation, GABA potentiation, endogenous melatonin support.
Why bisglycinate, not oxide or citrate
This is the part most people miss. Form matters more than the milligrams.
| Form | Bioavailability | Side effects |
|---|---|---|
| Magnesium oxide | ~4% | Cheap; what's in CVS multivitamins |
| Magnesium citrate | ~30% | Laxative effect (osmotic) |
| Magnesium bisglycinate | ~80% | Gentle on GI; the glycine is itself sleep-active |
We use bisglycinate. Two glycine molecules bound to one magnesium ion. You absorb the magnesium efficiently, you don't get GI distress, and you get a small additional dose of the same glycine that's already in the stack.
The study
Abbasi et al. (2012) — eight-week trial in elderly subjects with insomnia. 500 mg of magnesium daily improved subjective measures of insomnia and serum cortisol levels.
Why 200 mg
Combined with the glycine and dietary intake, this lands most users in the optimal nightly range without overshooting. It also fits inside one cleanly dosed daily serving — you're not taking it on top of a multivitamin.
3. L-Theanine — 200 mg
What it does
L-theanine is the unique amino acid in green tea (especially matcha). It's the compound that makes matcha feel calmly focused instead of jittery, even though matcha contains caffeine.
At night, the same molecule does a different job: it quiets the mental noise that keeps you staring at the ceiling at 11 PM thinking about the email you didn't send.
The mechanism
Three actions, simultaneous:
- Increases alpha-wave activity in the brain — the "relaxed but alert" state, the same state you reach in meditation
- Modulates GABA, dopamine, and serotonin — gently raises calming neurotransmitters without sedation
- Dampens cortisol response to stress — your nervous system is less reactive to perceived threats
The study
Lyon et al. (2011) gave 200 mg of L-theanine to subjects with disordered sleep. The result: improved sleep efficiency and architecture (not just total time, but quality of phases) without next-day grogginess.
Why this matters
Most "sleep aids" sedate you. L-theanine doesn't. It quiets the noise so your nervous system can do what it already wants to do at 10 PM. Pair it with the slow rhythm of casein digestion and you get a stable, non-drugged feeling — calm, drifting, ready.
Why 200 mg
That's the studied dose for sleep applications. Most nootropic stacks use the same dose for daytime focus, which tells you everything: same molecule, same mechanism, different time of day.
4. Apigenin — 50 mg
What it does
Apigenin is the active sleep compound in chamomile. It's a bioflavonoid that modulates the GABA-A receptor — the same receptor that benzodiazepines target — but without the dependence profile, sedation, or next-day fog.
The mechanism
Selective binding to the benzodiazepine site of the GABA-A receptor. The result: anxiolytic (anti-anxiety) and mild sedative effects, mediated through the same brake pedal as the magnesium but at a different binding site. The two compounds compound on each other.
Apigenin also has a long half-life (estimates around 90 minutes for absorption, with sustained tissue levels for hours), which means it stays active through the first half of your sleep cycle when most deep sleep happens.
The study
Mao et al. (2016) ran a long-term randomized controlled trial of chamomile extract for generalized anxiety disorder. Result: significant reduction in anxiety scores. The active mechanism was traced to apigenin's GABA-A modulation. Subsequent in-vivo work has confirmed the dose-response curve.
Why we use 50 mg (and why a cup of chamomile tea isn't enough)
Studies use 50 mg of apigenin extract. A cup of chamomile tea contains roughly 0.4 mg of apigenin — about 125× less than the studied dose.
Drinking chamomile tea before bed is a lovely ritual. As an active sleep aid, it's homeopathic.
Moon Milk delivers 50 mg per serving. The same dose the studies actually used.
Why these four together
Each ingredient solves a different part of the sleep problem:
| Ingredient | Pillar | Mechanism |
|---|---|---|
| Glycine | Body temperature | Peripheral vasodilation, NMDA pathway |
| Magnesium bisglycinate | Nervous system state | Parasympathetic activation, GABA cofactor |
| L-theanine | Mental quietness | Alpha waves, neurotransmitter modulation |
| Apigenin | Receptor binding | GABA-A modulation |
Stacked, they cover the four most reliable, study-backed pathways your body already uses to enter and maintain sleep. Stacked at the studied doses, they actually move the endpoints those studies measured.
That's the difference between a "sleep blend" and a sleep stack.
How this fits with the casein
The other half of Moon Milk is 20 grams of slow-digest micellar casein protein. Casein digests over 6 to 8 hours, matching the length of a full sleep cycle, so amino acids stay elevated through the overnight rebuild instead of crashing in the first 90 minutes the way whey does (read: Casein vs Whey at Night).
The sleep stack creates the conditions for deep, restorative sleep. The casein gives your body the raw material to rebuild during it.
That's the whole product. One bag. Five compounds. One ritual.
Frequently asked
Will I become dependent on the sleep stack?
No. None of these four ingredients have established dependence pathways at the doses used. They support what your body is already trying to do, instead of overriding it (which is the issue with melatonin and benzos).
Can I take the sleep stack without the protein?
Mathematically, yes — but you'd be missing the protein-synthesis half of the product, which is the actual point of nighttime protein. The whole reason these four ingredients are paired with casein is that recovery is systemic. Sleep architecture and protein synthesis happen in parallel; supporting only one is leaving half the window unused.
What time should I drink it?
30 to 60 minutes before bed. Long enough for the magnesium and glycine to start the body-temperature drop and parasympathetic shift. Short enough that the casein is still digesting through your sleep cycle.
Does it interact with sleep medications?
The four ingredients are well-tolerated and have very few documented interactions, but anytime you stack things that modulate GABA (these all do, gently) with a prescription sleep medication, talk to your doctor first.
Why can't I just take these four supplements separately?
You can. We did the math: 4 SKUs at consumer markup is roughly $145 to $210 per month. Moon Milk is $50.99 a bag. The supplements aren't the only thing you're getting — you're also getting the casein protein, and you're getting them all in a 30-second ritual instead of a 5-bottle pile on your nightstand.
Related reading
- Nighttime Protein: The Overnight Recovery Window Explained
- Why Moon Milk Has Zero Melatonin
- Casein vs Whey at Night
- What Is Moon Milk?
Want the whole stack in one ritual? Moon Milk is 20g slow-digest casein plus the four-ingredient sleep stack at study-cited doses — magnesium bisglycinate 200 mg, glycine 3 g, L-theanine 200 mg, apigenin 50 mg.
Muscle isn't built in the gym. It's built while you sleep.
Sources
- Yamadera, W., et al. (2007). Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep and Biological Rhythms, 5(2), 126–131.
- Bannai, M., & Kawai, N. (2012). New therapeutic strategy for amino acid medicine: glycine improves the quality of sleep. Journal of Pharmacological Sciences, 118(2), 145–148.
- Abbasi, B., et al. (2012). The effect of magnesium supplementation on primary insomnia in elderly. Journal of Research in Medical Sciences, 17(12), 1161–1169.
- Lyon, M. R., et al. (2011). The effects of L-theanine on the components of sleep architecture. Alternative Medicine Review, 16(4), 348–354.
- Mao, J. J., et al. (2016). Long-term chamomile (Matricaria chamomilla L.) treatment for generalized anxiety disorder: A randomized clinical trial. Phytomedicine, 23(14), 1735–1742.
- Salehi, B., et al. (2019). The Therapeutic Potential of Apigenin. International Journal of Molecular Sciences, 20(6), 1305.