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evidence · mechanism · dose
Supplements/Amino Acid

L-Glutamine

Most abundant amino acid; primary fuel for enterocytes and immune cells.

Gut HealthImmune FunctionRecovery Optimization

Overview

Most abundant amino acid; primary fuel for enterocytes and immune cells.

Natural sources
  • Beef
  • Eggs
  • Dairy
  • Cabbage
Common forms
  • L-Glutamine

Forms & variants of L-Glutamine

Different chemical forms of L-Glutamine behave differently. Browse each form's mechanism, bioavailability, and best-use context.

Gut healing dose
L-Glutamine (Gut)

Primary fuel for enterocytes; supports tight junctions.

Mechanism of action

Primary nitrogen donor; enterocyte and lymphocyte fuel.

Pathways
  • · Glutaminolysis
  • · Glutathione synthesis

Effects on the body

Supports
Intestinal barrier integrity
Supports
Immune cell function

Organ system effects

Digestive / Gut

May support recovery in IBS-D and chemo-related mucositis.

Evidence-based benefits

Reduces IBS-D severity in post-infectious

Moderate evidence

Reduces mucositis in chemotherapy

Moderate evidence

Potential side effects

Common
    Rare
      Serious

        Drug interactions

        Antiseizure meds
        May lower seizure threshold theoretically.
        minor

        Safety & non-supplemental interactions

        Educational summary — always confirm with your clinician or pharmacist before starting, stopping, or combining with prescription therapy.

        Avoid with these conditions
        • ·Autoimmune disease (theoretical immune activation)
        Avoid / monitor with these medications
        • ·Immunosuppressants

        Supplement interactions

        Pairs well with

        None listed.

        Avoid combining with

        No specific avoidances listed.

        Dosing & bioavailability

        Typical dose
        5 g 1–3×/day for gut; up to 30 g in clinical settings

        Where to buy

        Affiliate-style search links to reputable retailers. We don't endorse specific brands — verify third-party testing (USP, NSF, Informed Sport) before purchase.

        Amino Acid
        L-Glutamine
        Amazon
        Wide selection · fast shipping
        Amino Acid
        L-Glutamine
        iHerb
        Global delivery · curated brands
        Amino Acid
        L-Glutamine
        Thorne
        Practitioner-grade · NSF tested

        Scientific evidence (9)

        Systematic reviewExamine.com Supplement Database · 2023

        L-Glutamine: pharmacology, clinical evidence, and safety — narrative review

        Examine.com Research Team

        Curated narrative review of human and preclinical evidence for L-Glutamine, including mechanism, typical dosing, and safety considerations.

        Key findings

        Best-supported outcome: Reduces IBS-D severity in post-infectious (evidence: moderate). Additional outcomes and limitations summarized in the full profile.

        Open study
        Systematic reviewPubMed (NLM) · 1970

        PubMed: L-Glutamine — Reduces IBS-D severity in post-infectious

        Live PubMed search

        Live results for "L-Glutamine Reduces IBS-D severity in post-infectious" across the PubMed/MEDLINE peer-reviewed index.

        Key findings

        Opens current human and preclinical literature matching L-Glutamine and "Reduces IBS-D severity in post-infectious". Filter by RCT, meta-analysis, or year on the results page.

        Open study
        Systematic reviewPubMed (NLM) · 1970

        PubMed: L-Glutamine — Reduces mucositis in chemotherapy

        Live PubMed search

        Live results for "L-Glutamine Reduces mucositis in chemotherapy" across the PubMed/MEDLINE peer-reviewed index.

        Key findings

        Opens current human and preclinical literature matching L-Glutamine and "Reduces mucositis in chemotherapy". Filter by RCT, meta-analysis, or year on the results page.

        Open study
        Systematic reviewPubMed (NLM) · 1970

        PubMed: L-Glutamine — randomized controlled trial

        Live PubMed search

        Live results for "L-Glutamine randomized controlled trial" across the PubMed/MEDLINE peer-reviewed index.

        Key findings

        Opens current human and preclinical literature matching L-Glutamine and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

        Open study
        Systematic reviewPubMed (NLM) · 1970

        PubMed: L-Glutamine — meta-analysis

        Live PubMed search

        Live results for "L-Glutamine meta-analysis" across the PubMed/MEDLINE peer-reviewed index.

        Key findings

        Opens current human and preclinical literature matching L-Glutamine and "meta-analysis". Filter by RCT, meta-analysis, or year on the results page.

        Open study
        Systematic reviewPubMed (NLM) · 1970

        PubMed: L-Glutamine — pharmacokinetics

        Live PubMed search

        Live results for "L-Glutamine pharmacokinetics" across the PubMed/MEDLINE peer-reviewed index.

        Key findings

        Opens current human and preclinical literature matching L-Glutamine and "pharmacokinetics". Filter by RCT, meta-analysis, or year on the results page.

        Open study
        Systematic reviewPubMed (NLM) · 1970

        PubMed: L-Glutamine — safety adverse events

        Live PubMed search

        Live results for "L-Glutamine safety adverse events" across the PubMed/MEDLINE peer-reviewed index.

        Key findings

        Opens current human and preclinical literature matching L-Glutamine and "safety adverse events". Filter by RCT, meta-analysis, or year on the results page.

        Open study
        Systematic reviewPubMed (NLM) · 1970

        PubMed: L-Glutamine — dose response

        Live PubMed search

        Live results for "L-Glutamine dose response" across the PubMed/MEDLINE peer-reviewed index.

        Key findings

        Opens current human and preclinical literature matching L-Glutamine and "dose response". Filter by RCT, meta-analysis, or year on the results page.

        Open study
        Systematic reviewGoogle Scholar · 1970

        Google Scholar: L-Glutamine — clinical evidence

        Live Scholar search

        Cross-database citation index for L-Glutamine as it relates to "clinical evidence".

        Key findings

        Includes preprints, theses, and journal articles. Useful for tracking citation counts and follow-on work.

        Open study
        Educational use only. This profile is not medical advice. Consult a qualified healthcare professional before starting any supplement, especially if you take prescription medication or have a chronic condition.