Tyrosine (Urine)

- Increased tyrosine may exacerbate migraine headaches and hyperthyroid conditions.

- Elevated tyrosine levels may occur due to supplementation (phenylalanine or tyrosine), heritable enzyme defects, or liver disease.

- High levels may indicate an inability to utilize tyrosine properly, perhaps because of low levels of enzyme co-factors such as iron, copper, iodine, B6, and vitamin C. 

- Tyrosine is derived from dietary protein and, endogenously from the essential amino acid phenylalanine.

- Tyrosine is not only a constituent amino acid of proteins and enzymes but, importantly it is the precursor in the synthesis of dopa, dopamine, norepinephrine and epinephrine (adrenaline).

- Tyrosine is also iodinated to form the thyroid hormones. Hence a chronic deficiency of tyrosine can result in hypothyroidism, adrenal catacholamine deficiency and impaired neurotransmitter metabolism.

- Tyrosine deficiency can be associated with behavioral and learning disorders, depression, anxiety and inability to deal with stress, and symptoms commonly exhibited with hypothyroidism.

- Tyrosine has been used in the treatment and withdrawal of cocaine abuse.

- Low urinary tyrosine can result from phenylalanine deficiency, protein malnutrition or malabsorption, or impaired conversion of phenylalanine to tyrosine that may result in phenylketonurea.

- Whole food sources that are relatively high in tyrosine include meats, poultry, wheat germ, cottage and ricotta cheeses, soy protein, cashews and lentils. Most fruits, vegetables and cereals are low in tyrosine.

- Implicated in depression, hypothyroidism, blood pressure disorders. If phenylalanine is normal or high, iron, Vitamin C, and Niacin supplementation may help to convert phenylalanine to tyrosine. 

- Low tyrosine relative to phenylalanine could also suggests that tetrahydrobiopterin (BH4) might be low. 

Tyrosin is the non-essential amino acid precursor for dopamine, norepinephrine and epinephrine. Tyrosine hydroxylase converts tyrosine into the dopamine precursor L-DOPA; BH4, Vitamin D and iron are cofactors for that enzymatic activity.