Glutamine is an amino acid, the building block for proteins, which is found naturally in the body. Glutamine might help gut function, the immune system, and other essential processes in the body, especially in times of stress. Glutamine levels also may drop if you are over training and not getting the right nutrients and supplements that your body needs. Glutamine helps with the production of muscles and supports your immune system. This supplement is essential and great for anyone who might be cutting, losing fat and trying to maintain muscle at the same time.