Definition of Aspartame
Aspartame: A man-made sweetener with almost no calories used in place of sugar.
Aspartame is a compound of two amino acids -- aspartic acid and phenylalanine. Because it is essentially half phenylalanine, people who have the genetic disease phenylketonuria (PKU) and cannot metabolize phenylalanine normally need to avoid diet drinks and other products containing aspartame (trade name: NutraSweet).