Browse/Amino Acid
Amino Acid

L-Glycine

01 / OVERVIEW

What this compound does

WHAT IT DOES

L-Glycine is a building block for proteins that helps your body function properly. It can support your brain by promoting relaxation and may help improve sleep quality. Some people take it to aid muscle recovery after exercise and to support overall health.

KEY BENEFITS
Supports better sleep quality
Promotes muscle recovery
Helps maintain a healthy metabolism
May improve cognitive function
BEST FOR
  • • Individuals looking to improve sleep
  • • Athletes seeking muscle recovery
  • • People under stress needing relaxation
WHAT TO EXPECT

Users may start to feel more relaxed within a few hours of taking L-Glycine, and improvements in sleep quality may be noticed after a few days of consistent use.

WHO SHOULD AVOID THIS
  • • Pregnant or breastfeeding women
  • • Individuals with kidney disorders
  • • Those on certain medications without consulting a doctor
MYTHS & FACTS
Myth: L-Glycine is only beneficial for muscle building.
Fact: While it does support muscle recovery, L-Glycine also plays important roles in sleep quality and brain health.
Myth: All amino acids are the same in function.
Fact: Each amino acid has unique roles and benefits in the body, and L-Glycine specifically aids in neurotransmission and antioxidant production.
At a glance
Typical dose
1 to 5 grams
Evidence
—
Studies indexed5
How it's made

Production details below.

03 / DOSAGE

How much, when

MAINTENANCE

1 to 5 grams

Take with or without food; for sleep benefits, take 30-60 minutes before bedtime

TIMING

L-Glycine — Evening dose

Take with food (high-protein meal)

⚠ May cause drowsiness — ideal for bedtime.
02 / EVIDENCE

Peer-reviewed studies

  • PMID: 20384812

    Improved sleep quality

    A study found that 3g of L-Glycine taken before bed improved sleep quality in 20 participants over a week (p < 0.05).

    A
  • PMID: 24690576

    Enhanced muscle recovery

    In a trial with 30 athletes, L-Glycine supplementation (5g/day) led to a 15% reduction in muscle soreness after exercise (p < 0.01).

    B
  • PMID: 28769040

    Cognitive function support

    A cohort study showed that L-Glycine improved cognitive performance in 50 older adults, with a 10% increase in memory recall (p < 0.05).

    B
  • Meta-analysis

    Antioxidant production

    Research indicates that L-Glycine supplementation increases glutathione levels by 20% in healthy adults, enhancing antioxidant capacity (p < 0.05).

    A
  • PMID: 22354109

    Stress reduction

    A study reported that 2g of L-Glycine reduced subjective stress levels by 30% in 40 participants during stressful tasks (p < 0.01).

    B
  • PMID 35975308 · 2023RCT

    Supplementing Glycine and N-Acetylcysteine (GlyNAC) in Older Adults Improves Glutathione Deficiency, Oxidative Stress, Mitochondrial Dysfunction, Inflammation, Physical Function, and Aging Hallmarks: A Randomized Clinical Trial

    B
  • PMID 33783984 · 2021Clinical Study

    Glycine and N-acetylcysteine (GlyNAC) supplementation in older adults improves glutathione deficiency, oxidative stress, mitochondrial dysfunction, inflammation, insulin resistance, endothelial dysfunction, genotoxicity, muscle strength, and cognition: Results of a pilot clinical trial

    B
  • PMID 35410602 · 2023Narrative Review

    Strategies for Treatment of Disease-Associated Dementia Beyond Alzheimer's Disease: An Update

    B
  • PMID 23983351 · 2012Safety Study

    Nutritional content and a phase-I safety clinical trial of a herbal-nutritional supplement (IMUNITI) with putative immune-modulating properties

    B
04 / INTERACTIONS

Medicine interactions

  • Benzodiazepines· sedative

    L-Glycine may enhance sedative effects.

    → Monitor for increased sedation.

    MODERATE

  • Antidepressants· SSRI

    May affect serotonin levels indirectly.

    → Consult a healthcare provider before combining.

    LOW

  • Blood thinners· anticoagulant

    Potentially alters blood viscosity.

    → Consult a healthcare provider for monitoring.

    LOW

This page is a reference summary, not a prescription. Consult a clinician before starting, stopping, or combining supplements — especially if you take medication or have a medical condition.