By Dr Ananya Mandal, MD
Glutamine is one of the twenty amino acids, the individual building blocks that join together to make up proteins in the body.
Glutamine has an amide side-chain that is formed when the side-chain hydroxyl of glutamic acid is replaced with an amine group.
When a gene is expressed, three consecutive base pairs code for a particular amino acid. Through connection of these amino acids, a polypeptide chain is made that eventually forms a protein. As one of these amino acids, glutamine is coded for by the base pairs CAA and CAG (Where C stands for cytosine, A for adenine and G for guanine).
Glutamine is the most abundant free amino acid found in human blood and has a concentration of around 500-900 µmol/l. It is considered a conditionally essential amino acid. Essential amino acids are those that cannot be produced by the body and must therefore be consumed in the diet. A conditionally essential amino acid is one that may stop being produced by the body in specific diseases conditions such as prematurity or severe catabolic distress.
Glutamine is also one of the few amino acids that can directly cross the blood–brain barrier. In humans, glutamine is found free in circulating blood and is also stored in the skeletal muscles.
In cases of long-term illness or injury, the amount of glutamine in the body is depleted and therefore needs to be supplemented in the diet. Glutamine has been a popular subject of research over the last couple of decades and studies have shown it to be beneficial for treating burns, trauma, injury and some side effects of cancer treatment.
The substance is also sold as a muscle growth aid to body builders, weight lifters and other athletes.
Reviewed by Sally Robertson, BSc
Last Updated: Jul 20, 2014