L-Phenylalanine is an essential amino acid, meaning it cannot be made by the body and must be obtained from food. As an amino acid, L-Phenylalanine provides the building blocks for protein, which is needed for the body’s normal growth and development.DirectionsAs a food supplement for adults, one (1) vegetable capsule daily with juice or water in between meals, or as directed by a healthcare practitioner. IngredientsEach vegetable capsule of Solgar L-Phenylalanine 500mg provides: L-Phenylalanine 500mg. Natural IngredientsDibasic calcium phosphate, magnesium stearate.Vegetable capsule shellHydroxypropylmethyl cellulose.