Aspartame (L-alpha-aspartyl-L-phenylalanine methyl ester) is a low-calorie sweetener used to sweeten a wide variety of low calorie foods and reduced calorie foods and beverages, including low-calorie tabletop sweeteners. Aspartame is composed of two amino acids, aspartic acid and phenylalanine, as the methyl ester. Amino acids are the building blocks of protein. Aspartic acid and phenylalanine are also found naturally in protein containing foods, including meats, grains and dairy products. Methyl esters are also found naturally in many foods such as fruits and vegetable and their juices. Upon digestion, aspartame breaks down into three components (aspartic acid, phenylalanine and methanol), which are then absorbed into the blood and used in normal body processes. Neither aspartame nor its components accumulates in the body. These components are used in the body in the same ways as when they are derived from common foods.
Further, the amounts of these components from aspartame are small compared to the amounts from other food sources. For example, a serving of no-fat milk provides about 6 times more phenylalanine and 13 times more aspartic acid compared to an equivalent amount of low calorie diet beverage sweetened 100% with aspartame. Likewise, a serving of tomato juice provides about 6 times more methanol compared to an equivalent amount of diet beverage with aspartame.
The food safety authority in Europe, the Scientific Committee on Food (SCF) of the European Commission, has reconfirmed aspartame's clean bill of health following a comprehensive review of the sweetener's safety. The SCF is a body of independent scientific experts which advises the European Commission on matters of food safety; its aspartame report was issued on December 10, 2002. (Original SCF Report - PDF)
On December 18, 2002, the United Kingdom's Food Standards Agency (FSA) issued a statement announcing that "the Agency supports the conclusions of the Committee's [Scientific Committee on Food] thorough and timely review on the safety of the sweetener [aspartame]." (Original FSA Report)
The French Food Safety Agency (AFSSA) recently completed a two year study by the French Expert Committee on Flavourings, Food Additives and Processing Aids and has confirmed the safety of aspartame once again. The AFSSA was asked to review an alleged link between aspartame and brain tumors. The report noted, "In conclusion, AFSSA considers that the current state of scientific knowledge does not enable a relationship to be established between the exposition to the aspartame and brain tumors in humans or animals. (Original AFSSA Report)