Histidine (Plasma)

– High histidine levels may indicate excessive protein intake or the breakdown of skeletal muscle.

– If 3-Methylhistidine also high, muscle protein breakdown is indicated.

– Low histidine levels have been associated with rheumatoid arthritis or a deficiency of the B vitamin folic acid. Salicylates (aspirin-like compounds) and steroids can also decrease histidine levels.

– Low histidine may be caused by too much lysine or arginine supplementation competing for absorption.

– Check dietary protein, or malabsorption if other essential AAs are low.

– Low histidine is associated with rheumatoid arthritis, folate deficiency, and/or salicylate/steroid use. Folate deficiency would be consistent with a partial methylation cycle block.

Histidine is the amino acid most necessary during stress. Amino acids are the building blocks of protein in our bodies.