Functions of L-Tyrosine in the Body
- Improves mental energy, mood and alertness
- Helps the body better deal with stress
- Aids in the manufacture of thyroxine (a thyroid hormone)
- Is a pigment imparting agent in the skin and hair
- Helps prevent stress-induced hair loss, by maintaining the structural integrity of hair follicles and the hair strands they produce.
When there is an insufficient level of free L-tyrosine present in the brain, the synthesis of dopamine, norepinephrine and epinephrine decreases greatly.
The body partially depends on the supply of L-tyrosine from the diet and also from the conversion of L-tyrosine from the amino acid phenylalanine (phenylalanine converts to tyrosine in the liver).
Today’s modern diet is extremely low in L-tyrosine (and L-phenylalanine, an essential amino acid, meaning it can only be obtained through diet or supplementation), which can consequently cause a deficiency in the body. Sequentially, this can lead to a decreased synthesis of these very important neurotransmitters – dopamine, norepinephrine and epinephrine.
The conversion of L-tyrosine to norepinephrine can be enhanced by the cofactors, vitamins C and B6. Vitamin B6 has already been added to this amino acid.
Tyrosine also aids in the manufacture of thyroxine, one of the thyroid hormones and helps form melanin, a skin pigment. It also helps the body better deal with stress, as well as helping to maintain the structural integrity of hair follicles and the hair strands they produce.
- Most amino acids come in two forms; D- or L- (such as L-tyrosine or D-tyrosine). D-amino acid is a mirror image of the L- amino acid – in other word the D- form is a backward image. Both can be taken. However, the L- form is preferable as it is the exact image of the amino acid in its natural form found in the body. The L- form is considered the more effective for overall human health.
L-Tyrosine 500mg, Vitamin B6 (as pyridoxine HCL).
Other Ingredients: Gelatin, water (capsules), magnesium stearate, cellulose, vegetable stearin and silica.
Contains No sugar, salt, dairy, yeast, wheat, gluten, corn, soy, preservatives, artificial colours or flavours.
As a dietary supplement, adults take one (1) capsule one (1) to four (4) times daily between meals, or as directed by a healthcare professional. Store in a cool, dry place, away from direct light.
Do not exceed the recommended daily dose. Keep out of reach of young children. Nutritional supplements should not replace a varied and balanced diet and a healthy lifestyle.Children, pregnant women and women who are breastfeeding, should consult their doctor before use. Check with simultaneous intake of medicines. No long-term use without professional advice.
Individuals taking SSRIs (Selective serotonin reuptake inhibitor) or MAOs (Monoamine oxidase inhibitors) should avoid taking L-tyrosine. Also, some individuals may experience hypertension (high blood pressure), or migraines when taking tyrosine supplements. Both L-phenylalanine and L-tyrosine form tyramine, a substance that may trigger migraines. If taken to close to bedtime, insomnia may occur. Cancer patients should avoid supplementing with L-phenylalanine and L-tyrosine, as certain cancers depend on these amino acids to feed its growth. People with phenylketonuria, a rare metabolic disorder should not supplement with L-phenylalanine. Tyrosine may increase thyroid production as is is a precursor for its synthesis, therefore, individuals with a hyperactive thyroid should be wary.
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