Aspartame is an artificial sweetener that was discovered in 1965 and approved by the FDA in 1981, but there remains controversy over its safety. It is made of two amino acids, aspartic acid and phenylalanine. When consumed, aspartame breaks down into methanol which can damage the brain and nervous system. Long term consumption has been linked to numerous health issues like brain tumors, mood changes, and headaches. While still legal and used in many food products, some experts argue it should be avoided due to potential health risks.