​L-phenylalanine is a vital (essential) amino acid that is used in metabolism as a precursor for the production of L-tyrosine and the skin pigment melanin. In addition to its importance for the production of endogenous tissue, L-phenylalanine is particularly important for the production of various messenger substances. In addition to the thyroid hormones, the amino acid is ultimately rebuilt into the neurotransmitters dopamine, epinephrine and norepinephrine. While dopamine is also known as happiness hormone, epinephrine and norepinephrine have an effect on heart rate, blood pressure, alertness, alertness and motivation. - Essential, proteinogenic amino acid - From natural sources - In its natural L-shape - Suitable for vegetarians and vegans