The most abundant amino acid in muscles and blood, glutamine provides fuel for various cells of the immune system and is a critical component in wound repair. The body can make glutamine, but may not make enough when the body is under stress. Glutamine is found naturally in beans, brewer’s yeast, brown rice, dairy products, eggs, fish, legumes, meat, nuts, seafood, seeds, soy, whey, and whole grains.

Preliminary evidence suggests that glutamine might help prevent infections in people who are over-stressed and athletes who are overtrained - and thus immunosuppressed. Glutamine may also be useful as a nutritional supplement for people undergoing recovery from illness. Some scientists have also suggested that glutamine could be useful as a treatment for food allergies. This speculation is based on a theory called "leaky gut syndrome," where proteins leak through the wall of the digestive tract and enter the blood, causing allergic reactions. There is some evidence to support this theory as several studies have suggested that glutamine supplements might reduce leakage through the intestinal walls. Because of this glutamine supplements have been suggested for people with other digestive problems, such as irritable bowel syndrome, Crohn’s disease, and ulcerative colitis. However, there have also been trials that have found that glutamine supplements were of no benefit to these people. Glutamine may be of benefit to patients with HIV as it has been shown to increase levels of glutathione, which interferes with viral activation, as well as significantly increasing lean body mass. Based on glutamine’s role in muscle, the amino acid may be useful for athletes experiencing overtraining syndrome.

There are no known symptoms of glutamine deficiency.

Doses range from 1.5 to 6g daily, divided into several separate doses. The majority of healthy people do not need to take supplementary glutamine.

MAXIMUM SAFE LEVEL: Not established - glutamine is generally regarded as safe.

People who are hypersensitive to monosodium glutamate (MSG) should use glutamine with caution, as the body metabolises glutamine into glutamate. Individuals taking antiseizure medications, for example carbamazepine, phenobarbital, Dilantin (phenytoin), Mysoline (primidone), and valproic acid (Depakene), should only take supplementary glutamine under medical supervision. People with kidney or liver disease should consult their doctor before taking supplementary glutamine.