Glutamine, one of the most abundant amino acids in the body, supports the health of the cells lining the gastrointestinal tract and is important for immune function.1 Glutamine is depleted when the body is under stress, including the stress of surgery.2 Blood levels of glutamine decrease following surgery, and as they return to normal, their increase parallels the increase in immune cells.3 Two controlled trials have shown that the use of glutamine-enriched intravenous formulas, providing approximately 20 grams of glutamine per day, resulted in increased immune cell activity and shorter hospital stays.4 , 5 Double-blind studies report that patients receiving intravenous formulas supplemented with glutamine after surgery had better nutritional status and better health outcomes, including fewer infections and other complications, compared with patients receiving regular formulas.
The amino acid glutamine appears to play a role in several aspects of human physiology that might benefit athletes, including their muscle function and immune system.8 Intense exercise lowers blood levels of glutamine, which can remain persistently low with overtraining.9 Glutamine supplementation raises levels of growth hormone at an intake of 2 grams per day,10 an effect of interest to some athletes because of the role of growth hormone in stimulating muscle growth,11 and glutamine, given intravenously, was found to be more effective than other amino acids at helping replenish muscle glycogen after exercise.12 However, glutamine supplementation (30 mg per 2.2 pounds body weight) has not improved performance of short-term, high-intensity exercise such as weightlifting or sprint cycling by trained athletes,13 , 14 and no studies on endurance performance or muscle growth have been conducted. Although the effects of glutamine supplementation onimmune function after exercise have been inconsistent,15 , 16double-blind trials giving athletes glutamine (5 grams after intense, prolonged exercise, then again two hours later) reported 81% having no subsequent infection compared with 49% in the placebo group
The following information was provided from the University of Michigan, read more at the following link http://www.uofmhealth.org/health-library/hn-2856003