Occurrences in Nature

Glutamine is the most abundant naturally occurring, non-essential amino acid in the human body and one of the few amino acids that directly cross the blood-brain barrier. In the body, it is found circulating in the blood as well as stored in the skeletal muscles. It becomes conditionally essential (requiring intake from food or supplements) in states of illness or injury.

Dietary Sources

Dietary sources of L-glutamine include beef, chicken, fish, eggs, milk, dairy products, wheat, cabbage, beets, beans, spinach, and parsley. Small amounts of free L-glutamine are also found in vegetable juices.