This methylated form of histidine comes from muscle tissue, both dietary and endogenous, where it is part of the muscle proteins actin and myosin. A moderate level of urine 3-methylhistidine is normal.

3-Methylhistidine is a biomarker for meat consumption, especially chicken. It is also a biomarker for the consumption of soy products.

Elevated levels suggest either an inordinately high intake of dietary actin/myosin or accelerated catabolism of muscle tissue. 3-Methylhistidine excretion is increased after strenuous physical exercise and also occurs in muscle wasting conditions - dystrophies, lack of exercise, extended bed rest, terminal stages of severe illness. Convulsions and seizures also feature increased urinary 3-methylhistidine. There is some correlation between elevated 3-methylhistidine and increased need for vitamin B12, folic acid, methionine and perhaps histidine if it is marginal or low.

If these deficiencies show up elsewhere on this test, then even though protein is burning at a rate, the Krebs cycle is operating at a lower rate than normal. This is consistent with fatigue and low body temperature.

If Histidine is also high:

May indicate excessive protein intake. Muscle protein breakdown is indicated.

If Beta-Alanine is also high:

Possible cause for food sensitivity reactions when combined with low taurine and high Beta-Alanine due to impaired renal tubular resorption.