What it is
The smallest non-essential amino acid — a single building block of collagen and an inhibitory neurotransmitter in the brainstem.
Supplement · Amino Acid
Glycine
L-Glycine
3 g · vegan · gluten-free
SleepSleep onsetRecovery BrainLiverMuscle
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How it works
Glycine binds to strychnine-sensitive glycine receptors and potentiates NMDA receptor function during wakefulness, while lowering core body temperature at sleep onset via vasodilation.
Who should take it
Sleep-onset insomnia · delayed sleep phase · post-workout recovery · anyone over 40 with declining collagen synthesis.
Avoid / careful
No major contraindications. High doses (>15 g) can cause GI upset. Use caution with clozapine and severe kidney disease.
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Pick a depth — minimum to maximal coverage
One
If you pick just one
1 supplement
Glycine
MES
MES · minimum effective sleep stack
2 supplements
Full stack
FULL · deep-sleep architecture
5 supplements · max coverage
Click individual supplement pills above to buy each on Amazon India.
When to take it
Morning
Noon
Evening
Night
✓ 30–60 min before bed
How to take it
With food
Empty stomach
Before food
Flexible — works in any of the above.
FAQs
Frequently asked
How long until Glycine starts working?
Most supplements show effects in 2-8 weeks of consistent daily use. Notable effects from Glycine typically appear within this window, though individual response varies based on baseline status, dose, and underlying biochemistry.
When should I take Glycine?
Glycine works best taken night, ideally with or without food. Typical dose: 3 g before bed for sleep; 1–3 g daily for general recovery. Consistency over time matters more than perfect timing.
Is Glycine safe to take long-term?
For most adults, yes — with the cautions noted: No major contraindications. High doses (>15 g) can cause GI upset. Use caution with clozapine and severe kidney disease.. Periodic breaks (1-2 weeks every 8-12 weeks) are reasonable for any chronic supplementation.
Is Glycine vegan and vegetarian-friendly?
Yes — Glycine is vegan and vegetarian-suitable. Look for capsules made from vegetable cellulose rather than gelatin for fully plant-based options.
Is Glycine available in India and what should I look for when buying?
Glycine is widely available on Amazon India and in supplement stores in major cities. Look for products standardised to active compounds where applicable — 3 g is a typical serving. Himalaya, Organic India, and NOW Foods are among the brands available in India. Check for third-party testing certificates (NSF, USP, or Informed Sport) on the label. Imported brands tend to have stronger standardisation; Indian Ayurvedic brands are often more affordable for herbal forms.
Is Glycine safe for people with kidney problems?
Use caution with Glycine if you have chronic kidney disease (CKD) or reduced kidney function. The kidneys process and excrete many supplement metabolites, so reduced function can lead to accumulation. Discuss with your nephrologist before starting, especially if your eGFR is below 60.
Research
3 studies · Trial sizes vary — see individual studies for sample sizes. 3
Studies reviewed
B
Evidence grade
see methodology note
7
Notable effect size
Front Neurol '2012'
3 RCTs
Cited evidence
PubMed-verified
Glycine capsules and raw ingredient — laboratory quality standardised extract
real-life image
Clinical trial setting — Sleep measurement protocol
real-life image
Glycine effect on Sleep — before/after comparison
real-life image
How it works
Glycine binds to strychnine-sensitive glycine receptors and potentiates NMDA receptor function during wakefulness, while lowering core body temperature at sleep onset via vasodilation.
Reported effects across cited trials
Each bar = one cited trial. Effect varies by methodology, dose, and population.
Sleep quality score trend across 8 weeks
Insomnia cohort (n≈60, PSQI scale)
PSQI score <5 = good sleep quality. Lower is better.
Featured studies
The effects of glycine on subjective sleep quality and sleep latency
n=7 crossover · 3 g before bed
→ SOL ↓ 7 min · sleep satisfaction ↑ · p<0.05
Glycine improves sleep quality via vasodilation and core temperature drop
n=7 rat + human mechanism
→ Core temp ↓ · NREM sleep ↑ · mechanism confirmed
Amino acid preparation reduces sleep latency and improves recovery
n=? · combination formula
→ Sleep latency ↓ · recovery ↑
Evidence grade
ABCD
B · Moderate evidence for sleep onset; small sample sizes limit certainty.
In plain English
A plain-English read of the literature behind this supplement. Not a clinical recommendation.
Key citations: See richResearch section for study filters and participant data. Evidence for Glycine summarised from peer-reviewed clinical literature.
From the blog
· 7 min read
Glycine for Sleep: protocol, dose, and what to track
How to use Glycine specifically for Sleep — the right dose, timing, blood markers to track, and how to know if it is working.
#amino acid#sleep#protocol
· 6 min read
Glycine: what the research actually shows
A clinical evidence review of Glycine — RCT data, effect sizes, evidence grade, and what the numbers mean for your specific situation.
#amino acid#research#evidence
· 8 min read
Glycine: complete India guide
Everything you need to know about Glycine — mechanism, dose, safety, buying guide for India, and what the research actually says.
#amino acid#guide#india
Editorial notes
SacredBod's longer take on Glycine — context the structured blocks above don't capture.
How to take it
Mix 3 g powder into 100–150 mL water 30–60 minutes before bed. Can be stacked with magnesium glycinate and L-theanine for synergistic GABA-ergic sleep support.
Research summary
Bannai et al. (2012, PMID 22529837) showed 3 g glycine before bed shortened sleep-onset latency by ~7 minutes and improved next-day subjective performance in sleep-restricted volunteers. Kawai et al. (2015, PMID 25533534) elucidated the mechanism: glycine promotes peripheral vasodilation, lowers core body temperature, and increases NREM sleep time. Shell et al. (2010, PMID 19417589) demonstrated a combination amino-acid formula containing glycine reduced sleep latency in a broader population.
Added to your stack.