L-tyrosine is an amino acid that can be converted to dopamine, norepinephrine and epinephrine (adrenaline). These hormones are often reduced by stress, overwork and certain drugs and need to be replenished. Norepinephrine, for example, enhances mental energy levels that often induce a feeling of contentment. The conversion step from L-tyrosine to norepinephrine may be enhanced if the co-factors (vitamins B6 and C) are included.
L-tyrosine also functions as a precursor to thyroid hormones, encephalins and melanin.
Cells in the adrenal medulla synthesise and secrete norepinephrine and epinephrine. Since both of these hormones can cause smooth muscle (arterial) contraction, care with blood pressure should be taken when supplementing with L-tyrosine.
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