Phenylalanine is an essential amino acid, a building block of protein that you must obtain through your diet because the body does not make it naturally. There are three forms of phenylalanine: L-phenylalanine, which is found naturally in protein sources, D-phenylalanine, which is created in a laboratory, and DL-phenylalanine, which is a combination of the two. Normal blood phenylalanine levels are 1 to 2 mg/dl. It is recommended that adults consume 14 mg of phenylalanine per kilogram of body weight from food daily.
Step 1
Eat eggs. Egg whites are one of the best food sources of phenylalanine. A 3.5 oz. serving of egg whites provides nearly 5,000 mg of phenylalanine, while whole eggs contain 2,515 mg per 3.5 oz. serving. You can use eggs and egg whites to make omelets, scrambled eggs and other breakfast dishes. You can also use powdered egg whites.
Step 2
Consume protein-rich foods. In general, most foods that are high in protein contain phenylalanine, as it is part of a complete protein. Including meat, poultry and fish in your diet provides adequate amounts of phenylalanine. A 3.5 oz. serving of beef provides about 1,400 mg of phenylalanine and 3.5 oz. of fish provides around 2,300 mg.
Step 3
Consume soy. Soy products are all good sources of phenylalanine, but the amounts vary by the product. Soybeans contain 2,122 mg per 3.5 oz. serving, while soy protein isolates contain up to 4,600 mg for the same weight. Other soy products, such as soy flour, tofu and soy meal, contain varying amounts.
Step 4
Eat nuts and seeds, which provide the body with healthy fats, contain protein and are, therefore, good sources of phenylalanine. Sunflower seeds contain the most at 2,466 mg per 3.5 oz. serving, while peanuts contain the least, at 1,427 mg per 3.5 oz. serving.
Step 5
Consume dairy products like milk, cheese and yogurt, which are also complete protein sources. Phenylalanine content varies by the type of cheese, from 1,400 to 2,200 mg per 3.5 oz. Dried milk is much more nutritionally concentrated than regular milk, containing about 1,700 mg per 3.5 oz. You can be easily add it to soups and smoothies for an extra phenylalanine boost.
References
- "Krause's Food, Nutrition, and Diet Therapy"; L. Kathleen Mahan, et al.; 2000
- University of Maryland Medical Center; Phenylalanine; Steven D. Ehrlich, NMD; June 2009
- Nebraska Health and Human Service System; Phenylketonuria Information
