Glutamine
The most abundant non-essential amino acid in the body. Plays a key role in maintaining intestinal barrier integrity and fueling immune cells. While blood glutamine drops after intense exercise, multiple RCTs have not confirmed benefits for muscle strength, hypertrophy, or performance in healthy individuals.
An ingredient with still-limited research
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Effects reported in research
Support for intestinal barrier function (research on gut protection during intense exercise and post-surgery)
Mitigation of temporary immune suppression after intense training (limited evidence)
Suggested positive effects on gut microbiome (still under investigation)
Dosage & timing
- Research uses 5–20 g/day.
- Often taken post-workout or before bed.
- Additional benefit is limited when adequate dietary protein is consumed.
Cautions
- •Generally safe at typical doses.
- •Consult a doctor with kidney or liver disease.
- •Caution may be warranted in some neurological conditions due to conversion to glutamate.
Supporting research
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