Glycine and NAC
NAC provides cysteine while glycine provides another rate-limiting precursor; together they are more effective at raising glutathione than either alone (GlyNAC protocol).
Glycine
A calming amino acid for sleep, collagen, and metabolic health.
NAC
A powerful antioxidant precursor and lung-health support compound.
Great to combine
These two are frequently stacked together; they complement each other and are commonly taken at the same time.
How to take them
Glycine
- Dose
- 3 g before bed for sleep; up to 10 g/day for collagen support
- Timing
- 30–60 minutes before bed for sleep; with meals for collagen/metabolic goals
NAC
- Dose
- 600–1,800 mg per day in divided doses
- Timing
- With food to reduce GI upset
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Frequently asked
Can you take Glycine and NAC together?
Yes, they are commonly taken together. NAC provides cysteine while glycine provides another rate-limiting precursor; together they are more effective at raising glutathione than either alone (GlyNAC protocol).
What's the best time to take Glycine and NAC?
Around the same time works well. Glycine: 30–60 minutes before bed for sleep; with meals for collagen/metabolic goals. NAC: With food to reduce GI upset.
How do Glycine and NAC interact?
Synergy: Work better together than alone. NAC provides cysteine while glycine provides another rate-limiting precursor; together they are more effective at raising glutathione than either alone (GlyNAC protocol).
Related pairings
Glycine + Magnesium
A sleep pairing with a built-in shortcut: magnesium glycinate is magnesium bound to glycine, so that form already delivers both. A standalone 3 g dose before bed (the amount sleep studies used) tops up the glycine, lowering core body temperature while magnesium relaxes muscles and calms the nervous system.
Collagen + Glycine
Glycine makes up about a third of collagen, so supplementing it provides raw material that collagen synthesis depends on.
Creatine + Glycine
Glycine is one of the three amino acids the body uses to synthesise creatine endogenously.
L-Glutamine + Glycine
Both are conditionally essential under stress and support gut and immune function through complementary pathways.