L-Tyrosine

Tyrosine is considered a non-essential amino acid but this does not mean that under certain instances it is not vitally important. Tyrosine can be manufactured in the body from the essential amino acid phenylalanine. L-Tyrosine is found in relatively small concentrations in the body probably because it is metabolized rapidly. The manufacturing of this nutrient from phenylalanine is dependent upon copper, vitamin C, folic acid and niacin in the form of NADPH and NADH. Tyrosine is abbreviated as either TYR or by its one-letter abbreviation Y.

Function- Tyrosine is found in the highest concentrations in brain tubulin which is an intracellular protein important for the structure of neurons and relatively high in muscle. Tyrosine is found in rather small amounts in the white matter (cerebrum) of the brain (compared to glutamic acid, alanine, serine, taurine, and aspartic acid) and the cerebral spinal fluid.

Neurotransmitters- L-Tyrosine is able to pass through the blood brain barrier and is a precursor involved in the manufacturing of dopamine, L-dopa, epinephrine and norepinephrine. These neurotransmitters are vitally important to help maintain the health of the sympathetic nervous system. Tyrosine acts as a mood elevator; a lack of adequate amounts of tyrosine leads to a deficiency of norepinephrine in the brain, which in turn can result in depression.

Low levels of dopamine, L-dopa, epinephrine and norepinephrine are found in those suffering from Alzheimer’s disease. These neurotransmitters need L-tyrosine in order to be manufactured. The two major neurotransmitter pathways that are damaged in Alzheimer’s disease are the choline and tyrosine systems. Levels of choline and tyrosine (all amino acids for that matter) can be accurately measured far before disease sets in and therefore adequate supplementation can be administered for prevention.

Parkinson’s disease is characterized by rigidity, tremors, disturbed postural reflexes and decreased movement. It is known that this condition occurs when there is a dopamine deficiency in the striatal regions of the basal ganglia (gray matter in the cerebral lobes). L-Dopa is the primary treatment for Parkinson’s disease and is made from tyrosine. Prevention is a better choice than treating the disease when it is in its late stages. Nerve damage is nerve damage. Deficient amino acid testing can be accurately performed prior to symptoms of any disease related to low levels of neurotransmitters.

Hormones- L-Tyrosine attaches to iodine atoms and is necessary for the manufacturing of thyroid hormones (thyroxin and triiodothyronine). Not surprisingly, therefore, low plasma levels of tyrosine have been associated with hypothyroidism. Low thyroid is commonly found in depression. It is important to not chase the symptoms of the body but instead help balance the systems of the body to promote health and wellbeing.

Other
¡ Melanin, responsible for the pigment of your skin is derived from L-Tyrosine.
¡ Sex drive may be stimulated by supplemental L-Tyrosine by raising dopamine in the brain.
¡ L-Tyrosine may be essential for new born babies. When L-Tyrosine is administered to premature infants it reduces inflammation in the bowel reducing any chance of necrotizing enterocolitis.

Deficiency- Common symptoms associated with tyrosine deficiency is neurotransmitter deficiency, hypothyroidism, rest less leg syndrome, low blood pressure and low body temperature. Low levels of Tyrosine have been recorded regularly in cases of depression, hypertension, low sex drive, Parkinson’s disease, and carbohydrate cravings and are commonly depleted with prolonged stress.

Sources- Natural sources of tyrosine include almonds, avocados, bananas, pork, wild game, turkey, fish, cottage cheese, lima beans, pumpkin seeds, ricotta cheese, and sesame seeds. Tyrosine can also be produced from phenylalanine in the body.

Precautions- Tyrosine, phenylalanine, tryptophan and 5HTP could be used with caution if the individual is taking Monoamine Oxidase inhibitors (MAO). If you take these nutrients with MAO inhibitors there may an excessive spike in epinephrine, norepinephrine and/or serotonin. Anyone who takes prescription medication for depression should discuss necessary dietary restrictions with his or her physician.

Requirements- There is no Recommended Dietary Allowances (RDA) listed. Individual needs may differ due to clinical conditions, biochemical individuality and absorption. All sources of nutrients should be consumed in their most natural state, in the form of a variety of foods or supplements when necessary. Free form amino acid supplements are immediately absorbed by the body and should be consumed with natural occurring cofactors for best results. Consulting with a physician that is properly trained in the natural healing sciences and amino acid therapy may be needed for optimum results.

Written by Jerome Rerucha D.C.

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