Histidine (Urine)

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

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

- Histidine excretion is also high with histidine administration, in histidinemia, and in diabetic nephropathy.

Histidine is required for maintenance and growth of tissue, transport of copper, and it is the precursor of histamine (vasodilator). Histamine stimulates gastric secretions (HCL) and is necessary for proper digestion of food and assimilation of nutrients. Histidine is commonly low in patients with rheumatoid arthritis. Low histidine may result from protein malnutrition or gastrointestinal dysfunction.

– 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.

Histidine ameliorates fatigue, promotes clear thinking and concentration, reduces appetite, decreases anxiety, improves sleep and glucose homeostasis, and gives rise to histamine.