Glycine
Best-in-class: Glycine
A simple, sweet-tasting amino acid that acts as an inhibitory neurotransmitter, a building block of collagen and glutathione, and a mild body-temperature regulator for sleep.
How Glycine actually works
Glycine is one of the two main inhibitory neurotransmitters — it opens chloride channels at glycine receptors, hyperpolarising neurons and quieting them, particularly in the brainstem and spinal cord. It's also an obligatory co-agonist at NMDA receptors, so its effects aren't purely suppressive. The mechanism behind the sleep finding is more specific and more interesting than sedation: glycine promotes peripheral vasodilation, which dumps heat from the extremities and lowers core body temperature. A falling core temperature is one of the physiological triggers for sleep onset.
Glycine quick facts
| Suggested dose | 3 g before bed for sleep; higher for glutathione/metabolic goals. |
| How often | Daily |
| Who it's for | Sleep quality, glutathione support, collagen and metabolic health. |
| Best-in-class brand | Glycine |
✅ Clinically validated
- RCTs show 3 g before bed improves subjective sleep quality and next-day alertness.
- A rate-limiting amino acid for glutathione and collagen synthesis.
📊 Correlative data
- Low glycine availability is associated with impaired glutathione status and metabolic strain.
🧪 Theoretical / extrapolated benefits
- The GlyNAC (glycine + NAC) longevity work is exciting but early; broad anti-aging claims outrun current human data.
These tiers tell you how much human evidence exists — not how well something works. This is the research space, and most of what’s in here is new rather than disproven. Something sitting at “theoretical” usually means nobody has funded the trial, not that the trial was run and failed.
The trap runs the other way too: something can be clinically validated and still do very little for you specifically. A statistically significant result in a study population is not a promise about your body.
- ✅ Clinically validated — human randomised trials or meta-analyses support it. The strongest footing available.
- 📊 Correlative — observational or epidemiological data. Suggestive, and genuinely useful for direction, but it cannot establish cause.
- 🧪 Theoretical / mechanistic — the mechanism is understood and often demonstrated in cells or animals, and the human trial doesn’t exist yet. Unproven is not the same as ineffective. Plenty of what’s standard practice today sat here five years ago.
✗ is a safety flag, not a grade. Where you see it, the concern is harm — not a disappointing trial. A compound tested for one purpose and found not to help there can still be worth studying somewhere else, so a negative result never gets rendered as a cross. It sits alongside the tier, because something can be both well-studied and genuinely risky.
My job is to tell you which one you’re looking at, and let you make the call. Grading something low isn’t me dismissing it — it’s me refusing to oversell it. This is the research space, and being able to reason forward from a mechanism matters as much as waiting for the trial.
Underrated, cheap, and it tastes sweet enough to take neat. The evidence is for sleep quality and next-day alertness rather than knocking you out — people report waking less and feeling clearer in the morning rather than falling asleep faster. Three grams about an hour before bed is the studied approach. It's also the rate-limiting amino acid for glutathione synthesis and a major component of collagen, so there's a reasonable case for it beyond sleep.
Glycine — safety & side effects
- Very well tolerated. Soft stools and mild nausea at doses above about 15 g.
- No established toxicity or significant drug interactions.
- Caution with clozapine — glycine may reduce its effectiveness. Otherwise one of the genuinely benign options for sleep.
Not medical advice. If you take prescription medication or have a diagnosed condition, check this against it with a pharmacist or doctor — pharmacists are underused and free.
Where to get Glycine
Buy Glycine at Thorne →Get the complete breakdown for Glycine — inside the Academy alongside the full interactive Vault.
Unlock in the Academy — $10/mo →Bloodwork to run alongside Glycine
Run these before you start, and again after 8–12 weeks. A baseline you didn’t take is one you can never go back for.
| Marker | What it’s watching for |
|---|---|
| TSH (Thyroid-Stimulating Hormone) | Thyroid disease disrupts sleep in both directions |
| Ferritin | Low iron drives restless legs, a common hidden cause |
| Vitamin D (25-Hydroxy) | Associated with sleep quality and commonly low |
| Magnesium, RBC | The form worth measuring if you're dosing magnesium |
The Sleep Quality & Recovery panel covers these in one order — 11 markers, $172.35 with the discount applied.
Check results you already have → · All 102 markers A–Z
Glycine — frequently asked questions
What is Glycine?
A simple, sweet-tasting amino acid that acts as an inhibitory neurotransmitter, a building block of collagen and glutathione, and a mild body-temperature regulator for sleep.
What is the suggested dose of Glycine?
3 g before bed for sleep; higher for glutathione/metabolic goals. This is a general reference for education only — statements have not been evaluated by the FDA and this is not medical advice.
What are the researched benefits of Glycine?
RCTs show 3 g before bed improves subjective sleep quality and next-day alertness.
Who is Glycine for?
Sleep quality, glutathione support, collagen and metabolic health.
Where can I buy Glycine?
Coach Cam sources Glycine from Thorne, with 10% off auto-applied at checkout — use the buy link on this page.
Build your foundation with Coach Cam
The full Supplement Vault — 350 products across 14 categories with clinical, correlative & theoretical evidence, plus my Thorne partner links — lives inside the Academy alongside 237 peptides.
Join the Academy — $10/mo →What Glycine is used for
Glycine appears under 5 goals in the Vault’s goal router, grouped by the mechanism it works through rather than by how much trial evidence exists. Each link opens that pathway in full, with the alternatives beside it and the bloodwork that tests it.