Final answer:
Someone with PKU needs to avoid aspartame in their diet.
Step-by-step explanation:
PKU stands for Phenylketonuria, which is a genetic disorder that affects the body's ability to break down phenylalanine, an amino acid found in protein-rich foods. Since individuals with PKU cannot properly metabolize phenylalanine, they need to follow a strict diet that is low in this amino acid to avoid damaging their central nervous system and brain. One of the foods that needs to be excluded from the diet of someone with PKU is aspartame, an artificial sweetener that can be broken down into phenylalanine.