Tyrosine is an amino acid which is synthesized from phenylalanine in the body.
It is a precursor of the important brain neurotransmitters epinephrine, norepinephrine and
dopamine, which transmit nerve impulses and are essential to prevent depression. Dopamine
is vital to mental function and seems to play a role in sex drive.
Tyrosine is also used by the thyroid gland to produce one of the major hormones, Thyroxin.
This hormone regulates growth rate, metabolic rate, skin health and mental health. It is
used in the treatment of anxiety, depression, allergies and headaches. Animals subjected
to stress in the laboratory have been found to have reduced levels of the brain
neurotransmitter norepinephrine. Doses of tyrosine prior to stressing the animals prevents
reduction of norepinephrine.
Intake of Tyrosine is contraindicated for people taking antidepressants containing
monoamine oxidase (MAO) inhibitors, people with high blood pressure or skin cancer. It may
trigger migraine headaches. The main sources of tyrosine in the diet are meats, dairy
products and eggs.