Herbs of Gold Tyrosine 1000Herbs of Gold Tyrosine 1000 provides high strength tyrosine in a convenient tablet dosage form. Tyrosine is an essential precursor for the synthesis of neurotransmitters and thyroid hormones. Healthy thyroid function Nervous system health Healthy stress response Indications: Tyrosine is a non essential amino acid (synthesised from the essential amino acid phenylalanine) and is an essential precursor for a wide range biochemical reactions in the body.