Glutamine is the most abundant naturally occurring,
nonessential amino acid in the human body, and one of the few amino acids that can directly cross the
blood–brain barrier.
[7] Humans obtain glutamine through
catabolism of
proteins in foods they eat.
[17] In states where tissue is being built or repaired, like growth of babies, or healing from wounds or severe illness, glutamine becomes conditionally
essential.
[17]
Glutamine is safe in adults and in preterm infants.
[19] Although glutamine is metabolized to glutamate and ammonia, both of which have neurological effects, their concentrations are not increased much, and no adverse neurological effects were detected.
[19] The observed safe level for supplemental L-glutamine in normal healthy adults is 14 g/day.
[20]
