L-tyrosine is a non-essential amino acid, meaning that it cannot be manufactured by the body and is essential to obtain it via the diet. Tyrosine has a number of functions in the body including being a precursor for neurotransmitters. Note: This product is not intended to diagnose, treat, cure, or prevent any disease, nor should supplements be used as a substitute for a balanced diet. Not intended for pregnant/breastfeeding mothers or children under 18. Do not exceed the recommended dose.