Natural Factors L-Glutamine - 500 mg - An amino acid that can be found throughout the body, especially in the brain, gastrointestinal tract, muscles, and liver cells. After periods of physical stress, L-glutamine helps support a healthy immune system and digestive system, and helps restore depleted glutamine levels in the blood and muscle. This assists in repairing muscle tissue after intense exercise and can accelerate post-exercise recovery time. Additionally, L-glutamine improves energy levels and brain function, and helps maintain the integrity of the intestinal barrier.