Tyrosine amino acid

Tyrosine was first isolated from casein in 1849 and is abundant in insulin as well as the enzyme papain and can be synthesized from the amino acid phenylalanine in the body.

It is a precursor of the neurotransmitters epinephrine, norepinephrine and dopamine, all of them extremely important in the brain and transmits nerve impulses and prevents depression. Dopamine is also vital to mental function and seems to play a role in sex drive

Required for

The action of this amino acid in brain functions is clear with its link to dopamine as well as norepinephrine, but it is also helpful in suppressing the appetite and reducing body fat, production of skin and hair pigment, the proper functioning of the thyroid as well as the pituitary and adrenal gland.

It is used for stress reduction and may be beneficial in narcolepsy, fatigue, anxiety, depression, allergies, headaches as well as drug withdrawal. In a study, using soldiers, tyrosine proved effective in alleviating stress and keeping them more alert.

Deficiency indications

Tyrosine, a parent amino acid for skin, hair, and eye pigments and are involved in syndromes, known generally as oculocutaneous albinism, that are characterized by the failure to form melanin pigments, resulting in partial or complete albinism.

It is also the precursor amino acid for the thyroid gland hormones thyroxin, and a defect in this may result in hypothyroidism - an enlargement of the thyroid gland (goiter), severe growth failure, and retardation of central nervous system development.

A deficiency may also have symptoms of low blood pressure, low body temperature (including cold hands and feet) and "restless leg syndrome".

Dosage

The dosage listed is the Recommended Daily Allowance (RDA), but be aware that this dosage is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the toxicity level must be kept in mind.

Dosage levels are not confirmed but some experiments have been performed with people taking up to 5 - 7 grams per day, with no confirmed toxic levels, but people taking MAO inhibitors, who suffer from high blood pressure and have problems with skin cancer should not take supplementation of L-tyrosine, and should aim to limit their intake of food sources high in this nutrient.

Best used with

If taking a tyrosine supplement it is best to take it at bedtime, or with a high carbohydrate meal to prevent competition of absorption with other amino acids. Folic acid, copper and vitamin B6 is a good combination to have with this nutrient to maximize absorption and effectiveness.

Other interesting points

Tyrosine and tryptophan have with been used with some success in the treatment of cocaine abuse and in another study it was combined with the antidepressant Imipramine to treat chronic cocaine abuse where it was reported that the combination blocked the cocaine high and prevented the severe depression that accompanies withdrawal.

Tyrosine is found in food sources

Meat, dairy, eggs as well as almonds, avocados and bananas are good sources of this nutrient.

Tyrosine found in the following Zest for Life products

• Vitalyze energy boost multi nutrient capsule
• Millenium 2000 - Slimming and weight-loss capsules

Nutritional information

Underneath we have information page on vitamins, minerals, amino acids, trace elements, enzymes and various nutritional compounds that can impact greatly on your general health, well-being and longevity. Please note that these pages are for general information only and must not be used to treat or diagnose health concerns.