What it is
L-Glycine is the smallest amino acid, used as both an inhibitory neurotransmitter at NMDA receptors and as one-third of every collagen molecule.
Supplement · Amino Acid & Sleep / Collagen
L-Glycine
Glycine
3 g · vegan · gluten-free · 30 caps
insomniarestless-sleepdaytime-fatigue brainjointskin
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How it works
A pre-bed dose drops core temperature by promoting peripheral vasodilation — a known sleep-onset signal — and modulates NMDA tone for deeper sleep architecture. Daytime use feeds collagen synthesis.
Who should take it
Adults with shallow sleep or daytime fatigue, joint-load athletes, connective-tissue rebuilders. Cheap and broadly tolerated.
Avoid / careful
Caution with antipsychotic medications. No significant interactions otherwise.
When to take it
Morning
Noon
Evening
Night
How to take it
With food
Empty stomach
Before food
FAQs
Frequently asked
Can L-Glycine be taken with other sleep aids?
While generally safe, consult your healthcare provider before combining L-Glycine with other sleep medications to avoid additive effects.
How quickly can I expect to see results for sleep?
Many users report improved sleep onset and quality within the first week of consistent nightly dosing.
Is L-Glycine suitable for vegetarians and vegans?
Yes, L-Glycine is typically synthesized and is suitable for vegetarian and vegan diets.
Research summary
A plain-English read of the literature behind this supplement. Not a clinical recommendation.
Japanese RCTs (Inagawa et al.) showed improved subjective sleep quality and reduced next-day fatigue at 3 g pre-bed. Collagen biochemistry is well established.
From the blog
Editorial notes
SacredBod's longer take on L-Glycine — context the structured blocks above don't capture.
L-Glycine is a amino acid & sleep / collagen supplement. L-Glycine is the smallest amino acid, used as both an inhibitory neurotransmitter at NMDA receptors and as one-third of every collagen molecule.
How it works
A pre-bed dose drops core temperature by promoting peripheral vasodilation — a known sleep-onset signal — and modulates NMDA tone for deeper sleep architecture. Daytime use feeds collagen synthesis.
Who it’s for
Adults with shallow sleep or daytime fatigue, joint-load athletes, connective-tissue rebuilders. Cheap and broadly tolerated.
Dosage & timing
- Typical dose: 3 g
- Best time: night
- With food: empty-stomach
- Expected onset: Sleep effects within 3–5 nights.
India context
Availability on Amazon India is currently limited or import-only for this form. International brands (iHerb, NOW Foods, Doctor’s Best) ship to India with variable customs handling. Local Ayurvedic equivalents may offer overlapping benefits.
Safety
Caution with antipsychotic medications. No significant interactions otherwise.
Added to your stack.