Phenylalanine is an amino acid that builds proteins, neurotransmitters, and other crucial molecules in your body. The body can\u2019t produce phenylalanine, which makes it an essential amino acid we need to get from food [R<\/a>, R<\/a>].<\/p>\n Nutritional supplements can contain different forms of phenylalanine with unique mechanisms and health effects – we\u2019ll dive into details about each one.<\/p>\n Phenylalanine molecule has 2 different forms, L- and D-phenylalanine, which are \u201cmirror images\u201d with the same structure. As you can see in the image above, they are only differently oriented in space [R<\/a>].<\/p>\n L-phenylalanine<\/b> is the active form that occurs naturally in a variety of foods. Your body uses it to make proteins and other molecules [R<\/a>, R<\/a>].<\/p>\n D-phenylalanine<\/b> is the synthetic form made in the lab. Your body partly converts it to the L-form or eliminates it via urine, but it also has some specific health effects discussed below [R<\/a>, R<\/a>].<\/p>\n Supplements can contain either form or a mixture of their equal amounts, known as DLPA (DL-phenylalanine)<\/a>.<\/p>\n Most protein-rich foods<\/b> contain decent amounts of L-phenylalanine. These include [R<\/a>, R<\/a>]:<\/p>\n Eating a variety of good protein sources will grant you an optimal phenylalanine intake.<\/p>\n People with an inborn metabolic disorder called phenylketonuria (PKU)<\/b> should avoid all foods and supplements high in phenylalanine (more details in the \u201cSide Effects and Precautions<\/b>\u201d section) [R<\/a>].<\/p>\nStructure<\/b><\/span><\/h3>\n
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Phenylalanine Foods<\/b><\/span><\/h2>\n
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Health Benefits<\/b><\/span><\/h2>\n