Glycine
Also known as: free-form glycine.
Glycine is the second sacrificial-amine trap in the protocol alongside L-cysteine. Large doses are tolerable and cheap. Human trial evidence for sleep onset is strong; for acetaldehyde trapping it is mechanistic. Tier 2 because [L-cysteine](ingredient:l-cysteine) covers the same carbonyl-scavenging role with stronger dose response.
Where this fits in the system
What it does
Glycine is a free amino acid that forms a Schiff base with carbonyl compounds — including acetaldehyde. At gram doses it's a viable stoichiometric trap, and at the same dose it also drives inhibitory glycinergic neurotransmission and supports sleep-onset physiology.
How it works
Two mechanisms, one dose
- Chemical. The primary amine on glycine condenses with the carbonyl carbon of acetaldehyde to form a Schiff base, neutralizing it similarly to how L-cysteine does. The reaction is reversible but acts as a sink at the doses the protocol uses.
- Neural. Glycine is a major inhibitory neurotransmitter in the spinal cord and brainstem. At oral doses of 3 g it reaches sleep centers and produces measurable improvements in sleep-onset latency and early-night sleep architecture — which is exactly what alcohol disrupts.
Higher-tier options in the same role
| Goal | Best (Tier 1) | Strong support (Tier 2) | Situational (Tier 3+) |
|---|---|---|---|
| Acetaldehyde clearance | DHM (Dihydromyricetin), L-Cysteine, NAC (N-Acetyl Cysteine), Sulforaphane | Glycine | |
| Neurotransmitter modulation | DHM (Dihydromyricetin) | Glycine |
Buying guidance
Free-form glycine powder is the best value. It's mildly sweet and water-soluble; mix into the Afterburner water or tea. Avoid glycine blended into proprietary "sleep stacks" — the dose is usually too low.
Deep science · Glycine — deep dive
Why it's Tier 2
Glycine is softer than L-cysteine in both roles: the Schiff base is reversible (less thermodynamically committed than the thiazolidine trap), and it's outclassed at sleep support by dedicated tools. It's in the protocol because it does both jobs cheaply and doesn't compete with anything else — a free assist.