3. What happens to aspartame once it is ingested?
Following ingestion, aspartame is broken down in the digestive tract to form aspartic acid, phenylalanine and methanol. Therefore, hardly any aspartame gets in the blood.
The body rapidly metabolises both aspartic acid and methanol, without significantly increasing their concentration in the bloodstream, even for aspartame taken as a single dose equivalent to the entire Acceptable Daily Intake (ADI).
At high doses usually surpassing the ADI, the level of phenylalanine in blood may increase with the dose of aspartame given. However, high doses generally do not increase the blood level more than a normal meal - except for individuals affected by phenylketonuria disease (homozygous PKU). More...