By Dena McDowell, MS, RD

Glutamine is the most common non-essential branch chained amino acid in the human body. Glutamine breaks down into energy, which the body uses in the gastro-intestinal tract, kidneys, and immune system. The body creates glutamine from glutamate, a reaction that takes place in all tissues, including the brain and fat stores. Usually, the body can produce enough glutamine to maintain its own stores. In times of stress, however, the body may not be able to create enough glutamine to regulate cellular functioning. During this time, it is important to supplement the diet with food and vitamins containing glutamine.

Benefits of glutamine

Glutamine helps stimulate the immune system by providing energy to the macrophages and lymphocytes. Glutamine is also instrumental in gastrointestinal health. There, it maintains the mucosal cell integrity and prevents bacterial translocation during times of stress or malnutrition. Glutamine, along with human growth hormone and diet, has been successfully used to treat short bowel syndrome. Glutamine is also extremely helpful in reducing mucositis, also known as mouth sores. In the kidneys, glutamine helps maintain the acid base balance by donating ammonia to the urea cycle during alkalosis. In the stress response, glutamine becomes conditionally essential.

Dangers of low glutamine

Bodily losses of glutamine may cause:

• Weakening of the immune system
• Increased infection rate
• Slowed wound healing time
• Death (if more than 40% has been lost).

Patients treated for trauma, burns, AIDS, irritable bowel, ulcerative colitis, poor wound healing, cancer, and blood infections may all benefit from glutamine supplementation.

When to take glutamine supplements

Because dietary sources of glutamine are limited, a glutamine supplement is usually recommended when severe bodily trauma occurs. The standard dose is 10 grams, 3 times a day for 1 month after the trauma. Some companies add antioxidants and arginine to shorten healing time. If taken orally, glutamine powder can be mixed with water, juice, applesauce, or pudding. Some commercial supplement products contain glutamine in their protein mixture.

Glutamine may also be used in critical care situations when a patient is unable to eat orally. It can either be added to the patient's tube feeding (10 grams with 60 milliliters of water 3 times a day) or in IV feedings (30 grams a day may be added to the solution).

Side effects of supplementation

Common side effects include:

• Increased bowel frequency
• Coughing
• Hoarseness.

Less common side effects may include:

• Blood in urine or stools
• Changed skin color
• Chills
• Cold feet and hands
• Dizziness
• Increased heart rate
• Lower back pain
• Wheezing
• Fatigue
• Facial swelling.

If any of these symptoms are present when taking glutamine, discontinue use and contact your physician.

Recommended dosages

If you are taking glutamine, taper the dose. After 1 month, reduce the dose to 5 milligrams, 3 times a day. 2 weeks later, reduce the dose again to 2 grams per day, 3 times a week. 2 weeks after that, discontinue completely.

Some patients undergoing chemotherapy may choose to take a 10 milligram maintenance dose on the days between chemotherapy.