Glutamine is the most abundant amino acid (building block of protein) in the bloodstream . Several types of important immune cells rely on glutamine for energy. Without glutamine, the immune system would not function appropriately. Glutamine also appears to be necessary for normal brain function and digestion.

Glutamine helps to protect the lining of the gastrointestinal tract known as the mucosa. Because of this, some experts speculate that glutamine deficiency may play a role in the development of inflammatory bowel disease (IBD), namely ulcerative colitis and Crohn’s disease. These conditions are characterized by damage to the lining of the small or large intestines, which leads to inflammation, infection, and ulcerations (holes). In fact, some preliminary clinical research suggests that glutamine may be a valuable supplement during treatment of IBD because it promotes healing of the cells in the intestines and improves diarrhea associated with IBD.

Glutamine supplementation has long been known to maintain the health of the mucosa (inner lining) of the gastrointestinal tract and inhibit muscle wasting in critically ill patients. Keeping the intestinal mucosa healthy helps prevent infections such as peritonitis (inflammation of the peritoneum, the thin membrane that lines the abdominal wall and covers most of the organs of the body).

Animal studies indicate that a diet supplemented with glutamine may protect the lining of the intestine, inhibit the growth of bacteria, and improve survival rates in animals.

Due to its ability to support proper functioning of the digestive tract, glutamine is often used to counteract unexplained weight loss, sub-clinical protein deficiencies, and wasting syndromes which accompany such diseases as cancer, anorexia, and AIDS.

Supporting Research

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Akobeng AK, Miller V, Stanton J, Elbadri AM, Thomas AG. Double-blind randomized controlled trial of glutamine-enriched polymeric diet in the treatment of active Crohn’s disease. J Pediatr Gastroenterol Nutr. 2000;30(1):78-84.
Clark RH, Feleke G, Din M, et al. Nutritional treatment for acquired immunodeficiency virus-associated wasting using beta-hydroxy-beta-methylbutyrate, glutamine, and arginine: a randomized, double-blind placebo-controlled study. JPEN: J Parenter Enteral Nutr. 2000;24(3):133-139.
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