Aspartame is an artificial sweetener used in place of sugar in various consumer products such as soft drinks, gums, vitamins, cereals, tabletop sweeteners and candies. It is made from two primary amino acids, aspartic acid and phenylalanine. Since amino acids are prevalent in the everyday foods we normally eat, proponents of aspartame often cite this as proof that the sweetener is safe for consumption.

Prior to the invention of aspartame, the primary artificial sweetener used in soft drinks was saccharine. Because of saccharine's bitter aftertaste there was a market for a sweetener that was closer to the taste of real sugar. Aspartame was created in 1965 and since its FDA approval has appeared in the marketplace under different names such as Nutrasweet and Equal. Initially the FDA expressed concerns over the cancer causing potential of the sweetener, especially brain tumors and thus its approval was delayed pending further examination. However, after revisiting the issue and the associated studies, approval for use in food was authorized by the FDA in 1981.

Because of its low calorie content and comparable taste when compared to sugar and the explosion of the health and diet market in the food industry, aspartame has become more widely used. Today, the sweetener is used in over 6000 products worldwide.

Critics argue that the sweetener has many adverse health risks such as increased incidence of cancer, Alzheimer's disease and Parkinson's disease and that the low-calorie health benefits are overstated. Many cancer based studies have been conducted using laboratory animals, producing mixed results. Similar studies on humans who consume products containing aspartame have also been inconclusive. The FDA has addressed these concerns and concluded that there was 'no reason to alter its previous conclusion that aspartame is safe as a general purpose sweetener in food.' Though there are no agency approved studies that state that aspartame is potentially harmful, it remains controversial and has many detractors.