An infant with phenylketonuria (PKU) lacks an enzyme to digest phenylalanine. To avoid mental retardation from an accumulation of toxic materials, the infant can consume only prescribed amounts of:

Question

Quizplus · Accepted Answer

Milk contains phenylalanine, a substance that individuals with PKU cannot properly metabolize due to a lack of the necessary enzyme. Therefore, their intake of foods high in phenylalanine, like milk, must be carefully managed to prevent the accumulation of toxic substances that can lead to mental retardation.

An Infant with Phenylketonuria (PKU) Lacks an Enzyme to Digest