The artificial sweetener aspartame has been the subject of several controversies since its initial approval by the U.S. Food and Drug Administration (FDA) in 1974. The FDA approval of aspartame was highly contested, beginning with suspicions of its involvement in brain cancer, alleging that the quality of the initial research supporting its safety was inadequate and flawed, and that conflicts of interest marred the 1981 approval of aspartame, previously evaluated by two FDA panels that concluded to keep the approval on hold before further investigation. In 1987, the U.S. Government Accountability Office concluded that the food additive approval process had been followed properly for aspartame. The irregularities fueled a conspiracy theory, which the "Nancy Markle" email hoax circulated, along with claims—counter to the weight of medical evidence—that numerous health conditions (such as multiple sclerosis, systemic lupus, methanol toxicity, blindness, spasms, shooting pains, seizures, headaches, depression, anxiety, memory loss, birth defects, and death) are caused by the consumption of aspartame in normal doses.
Aspartame is a methyl ester of the aspartic acid/phenylalanine dipeptide. Potential health risks have been examined and dismissed by numerous scientific research projects. With the exception of the risk to those with phenylketonuria, aspartame is considered to be a safe food additive by governments worldwide and major health and food safety organizations. FDA officials describe aspartame as "one of the most thoroughly tested and studied food additives the agency has ever approved" and its safety as "clear cut." The weight of existing scientific evidence indicates that aspartame is safe as a non-nutritive sweetener.
Origins
The controversy over aspartame safety originated in perceived irregularities in the aspartame approval process during the 1970s and early 1980s, including allegations of a revolving door relationship between regulators and industry and claims that aspartame producer G.D. Searle had withheld and falsified safety data. In 1996, the controversy reached a wider audience with a 60 Minutes report that discussed criticisms of the FDA approval process and concerns that aspartame could cause brain tumors in humans. The 60 Minutes special stated that "aspartame's approval was one of the most contested in FDA history."
Around the same time, a Usenet post was widely circulated under the pen name "Nancy Markle", creating the basis for a misleading and unverifiable hoax chain letter that was spread through the Internet. Numerous websites have spread the email's claims, which were not supported by scientific evidence, about safety issues purportedly linked to aspartame, including Gulf War Syndrome and lupus.
U.S. FDA approval
Aspartame was originally approved for use in dry foods in 1974 by then FDA Commissioner Alexander Schmidt after review by the FDA's Center for Food Safety and Applied Nutrition. Searle had submitted 168 studies on aspartame, including seven animal studies that were considered crucial by the FDA. Soon afterwards, John Olney, a professor of psychiatry and prominent critic of MSG, along with James Turner, a public-interest lawyer and author of an anti-food-additive book, filed a petition for a public hearing, citing safety concerns. Other criticisms presented in the 1996 60 Minutes special of the Searle studies included assertions of unreported medical treatments that may have affected the study outcomes and discrepancies in the reported data. Schmidt agreed, pending an investigation into alleged improprieties in safety studies for aspartame and several drugs.
In December 1975, the FDA placed a stay on the aspartame approval, preventing Searle from marketing aspartame. The Searle studies were criticized by the FDA commissioner as "... at best ... sloppy and suffering from ... a pattern of conduct which compromises the scientific integrity of the studies."
U.S. Attorney Samuel Skinner was requested to "open a grand jury investigation into whether two of Searle's aspartame studies had been falsified or were incomplete." Skinner withdrew from the case when he was considering a job offer from the law firm Sidley & Austin, Searle's Chicago-based law firm, a job he later took. The investigation was delayed and eventually the statute of limitations on the charges against Searle expired and a grand jury was never convened.