Glutamine is a non-essential amino acid which one of the most abundantly, naturally occurring amino acids in the human body. It is also unique in that it is one the few amino acids which can directly cross the blood-brain barrier. Glutamine is found in the blood and skeletal muscles. Glutamine is also abundantly present in a large variety of foods including chicken, beef, eggs, dairy, whet, cabbage, beets, spinach, parsley etc and hence it’s very rare to have a glutamine deficiency. Supplements however may need to be taken in case of illness or injury. Glutamine has a major role in protein synthesis. It is also essential for regulating the acid-base balance in the kidney through the production of ammonium. Glutamine is a substrate for DNA synthesis and aids in immune function by acting as a precursor for rapidly dividing immune cells.