Other Name(s):

a-amino-b-[4-imidazole]-propionic acid


Histidine is reported to help treat allergies, ulcers, rheumatoid arthritis, and anemia. It is also considered beneficial in improving sexual function and protecting against damage caused by ionizing radiation (from X-rays, for example).

Recommended intake

Amino acids (AAs), such as histidine, are available as individual AAs or in proprietary AA combinations, as well as part of multivitamin formulas, proteins, and food supplements. The forms include tablets, fluids, and powders. However, adequate protein in the diet should provide a sufficient source of all amino acids.

There are no conditions that increase the nutritional requirements for histidine.

Side effects and toxicity

The use of a single amino acid supplement may lead to negative nitrogen balance, decreasing the metabolic efficiency and increasing the workload of the kidneys. In children, taking single amino acid supplements may also harmfully affect growth parameters.

Excess histidine may cause psychological disturbances and contribute to mood disorders. Generally, single amino acid supplements are not recommended for people who eat an adequate or even less than adequate amount of protein.

Always avoid taking individual amino acids in high doses for prolonged periods of time.

Women who are pregnant or breastfeeding should not use histidine supplements.


L-histidine has a molecular formula of C6H9N3O2 and a molecular weight of 155.2.

Additional information

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