Glutamine is a non-essential amino acid and its main function is the formation of proteins. There are two types of glutamine. These are L-glutamine and D-glutamine. While L-glutamine participates in the structure of proteins, D-glutamine is a slightly less important product for living organisms. L-glutamine can also be synthesized by the body.
When glutamate (glutamic acid), a non-essential amino acid, is broken down and combined with nitrogen containing ammonia molecules, glutamine is produced in the human body. In other words, glutamine attracts nitrogen and cleans the ammonia in the body. It transports nitrogen between tissues.

Glutamine is an essential amino acid for the immune system. It is essential for immune cells, white blood cells and some tissues. Some research shows that glutamine supplements can improve the immune system and reduce infections.

It is also thought that glutamine can improve the health of the intestinal system. Glutamine is also thought to protect metabolism against leaky gut syndrome.