Glutamine and Citruline for Peak Metabolic Fitness

Glutamine and citrulline are amino acids that are critical to metabolic fitness. Citrulline is partially made during reactions involving glutamine. Glutamine plays an important role in the function of the immune system. Many athletes take glutamine to recent upper respiratory infections and flu. It is the most abundant amino acid in the body but can be depleted during trauma, serious illness, or intense training.


Citrulline is an important amino acid involved in the formation of urea. It is a popular component in athletic food supplements because it participates in key amino acid reactions and influences blood flow by increasing nitric oxide levels. Nitric oxide is an important chemical secreted by the endothelium- the inner lining of the blood vessels.

Glutamine promotes wound healing and speeds recovery from serious illnesses, injury, trauma, and burns. Several studies found a relationship between depressed immune function and low levels of glutamine. A Baylor University study found that glutamine was not a significant amino acid for producing citrulline. Good dietart sources of glutamine include beef, chicken, fish, eggs, milk, dairy products, wheat, cabbage, beets, beans, spinach, and parsley, while watermelon rind is an excellent source of citrulline.