You are here

Phenylketonuria Diet

A phenylketonuria diet is indicated for patients who have the phenylketonuria (PKU) disease. This is a genetic condition where the patient cannot digest a material called as phenylalanine that is found in protein rich foods. High levels of phenylalanine in the blood can result in brain damage and even coma.

Characteristics of the Phenylketonuria Diet

Patients on the phenylketonuria diet have to restrict their dietary intake of several different kinds of proteins that contain phenylalanine. The exact safe level of phenylalanine differs from person to person. All babies that are born in US are evaluated for the occurrence of PKU. If the results are positive, dietary changes are prescribed for newborns and these changes have to be followed lifelong. Frequent blood tests are necessary to evaluate the amount of the phenylalanine in blood. Regular dietary changes will have to be done according to the results of the tests.

Phenylketonuria Diet Recommendations

Newborn babies are provided with special feeds that are free from phenylalanine. Fresh fruits and vegetables are ideal for such patients but even these food items have to be carefully calibrated to ensure that phenylalanine levels in blood does not increase.

Contraindicated foods on the Phenylketonuria Diet

All high protein foods are contraindicated on the Phenylketonuria Diet. Food items like milk, eggs, cheese, nuts, soybeans, beans, chicken, steak, fish, and peas, chocolate are all contraindicated. Artificial sweeteners like aspartame that are found in diet and low calorie drinks and food items are also contraindicated. Aspartame releases phenylalanine when digested aggravating the disease. Food items like pasta, rice, bread, cookies and fruits and vegetables should be avoided as much as possible.


Mayo Clinic