L-Glutamine

amino acids

★★★★★

L-Glutamine is a conditionally essential amino acid that serves as a primary fuel source for intestinal cells and supports immune function. It becomes essential during periods of intense stress, illness, or intense exercise when demand exceeds endogenous production.

Benefits

✓Supports intestinal barrier integrity

✓Enhances immune cell function

✓Promotes muscle recovery and protein synthesis

✓May improve gut health and reduce leaky gut

✓Supports nitrogen balance during catabolic states

Dosage

Typical Dose

5-10g daily

Upper Limit

20-30g daily

Timing

Post-workout or divided throughout the day with meals

Forms & Bioavailability

L-Glutamine powder

High absorption; rapidly utilised by intestinal and immune cells

Capsules

Good absorption; convenient but higher cost per serving

Side Effects

⚠Generally well-tolerated at recommended doses

⚠High doses may cause mild gastrointestinal discomfort

⚠Rare reports of dizziness or headache

Interactions

⚡May interact with lactulose and certain anticonvulsant medications

⚡No significant interactions with common supplements

Research Summary

Research supports L-glutamine's role in maintaining intestinal barrier function and immune support, particularly in critically ill patients and athletes. Some evidence suggests benefits for exercise recovery and gut health, though more rigorous human trials are needed. Generally recognised as safe with minimal adverse effects at physiological doses.

Compare L-Glutamine with...

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Where to Buy L-Glutamine

We recommend buying from reputable retailers. Check reviews and third-party testing.

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Disclaimer: This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement, especially if you have existing health conditions or take medication.