L-Glutamine is one of the most important nutrients for a healthy digestive tract because of its ability to maintain the integrity of the intestinal wall. This amino acid (in fact it’s the most abundant amino acid in the body) heals all tissue in the body, especially those irritated tissues in the digestive tract. It is also known as the calming amino acid since it’s very effective at reducing anxiety, as well as sugar and alcohol cravings. Some more progressive treatment centers will use it to reduce cravings.