The main benefit of glutamine is improved outcomes in trauma, burns, and injuries.[1] It has also been found to affect nitrogen balance (i.e., reduce protein depletion), improve immune function, and reduce infectious morbidity in adults going in for abdominal surgery for peritonitis (an infection of the abdomen).[2] In addition, glutamine may reduce gut permeability (lactulose/mannitol ratio), inflammation (IL-6, TNF-ɑ, C-reactive protein), hospital stay length, and mortality.[3]
In people undergoing radiation therapy for head and neck cancer, glutamine reduced the severity of oral mucositis. This painful condition results from the death of the cells lining the mouth and is often a reason to halt the course of radiation. Post-radiation, glutamine was found to reduce the use of analgesic opioids, nasogastric feeding, and treatment interruptions.[4]
In addition, glutamine may reduce symptom scores of irritable bowel syndrome (IBS) alongside a low-FODMAP diet.[5] Glutamine was found to have no significant effect in the context of Crohn’s disease, though sample sizes were small.[6][7][8][9]
Glutamine is commonly marketed as an exercise supplement, but there are no consistent observed effects on athletic performance from supplementation with glutamine. However, glutamine may increase white blood cell counts and benefit weight reduction.[10]