Histidine

Some interesting facts about histidine:

Histidine is an essential amino acid
Histidine is an essential amino acid. This means the body cannot make it at all, or not in sufficient amounts for good health and it needs to be eaten as part of the diet every day. Histidine is especially necessary for babies, infants and children.
Histidine functions as a building block of protein in the body
Histidine, just like all the other amino acids, is one of the building blocks of all proteins in the body, which not only include muscles, but also all the other proteins required for normal function of the body.
Histidine is present in all cells of the body
Studies have determined that there is a small amount of histidine in all tissues and cells of the body.

Histidine is required to help create sufficient quantities and healthy amounts of both the red blood cells and the white blood cells

Copper and methionine lower histamine levels
The essential amino acid methionine and the trace mineral copper both act to lower levels of histidine (and thus histamine) in the body - this has beneficial implications in lowering the allergic response.
Histidine is needed to make the red and white blood cells
Histidine is required to help create sufficient quantities and healthy amounts of both the red blood cells and the white blood cells.
Histidine has antioxidant properties
Histidine has antioxidant properties which studies have found help the body by scavenging for free radicals that would otherwise damage the tissues of the body. Various studies have confirmed that histidine's antioxidant properties prevent oxidation of body tissues, preventing ill health and disease.