Research

Mixed

Glutamine is a conditionally essential amino acid that serves as a primary fuel source for immune cells (lymphocytes, macrophages, neutrophils) and gut enterocytes, particularly during catabolic stress, sepsis, or intense exercise, where endogenous synthesis cannot meet demand.

If you are critically ill, recovering from major surgery, or suffering from severe sepsis, your body's demand for glutamine exceeds what it can produce. In these specific catabolic states, glutamine supplementation is often recommended to support immune cell function and gut integrity. For healthy, non-stressed individuals, endogenous production is usually sufficient, and the necessity of supplementation is less clear.

GoodSupportsHIGH confidence
Glutamine is the most abundant and versatile amino acid in the body... cells of the immune system, such as lymphocytes, neutrophils, and macrophages, utilize glutamine at high rates similar to or greater than glucose under catabolic conditions... Glutamine assumes the role of a conditionally essential amino acid in such deficiency conditions
Vínicius Fernandes Cruzat et al. · Nutrients · 2018

Why this rating

The paper is a comprehensive review citing numerous in vitro, in vivo, and clinical studies, though it notes variability in clinical outcomes.

Source

Glutamine: Metabolism and Immune Function, Supplementation and Clinical Translation

Vínicius Fernandes Cruzat et al. · Nutrients · 2018

DOI 10.3390/nu10111564

narrative_reviewCited 1,143×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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