Is Aspartame Responsible for Multiple Sclerosis?

For a decade, Nancy consumed diet soda daily, often drinking four or five cans. She maintained a balanced diet, exercised regularly, and ensured adequate sleep. One day, while lifting her glass of diet soda, it slipped from her grasp and shattered. Startled, she tried again but found her hand unresponsive. The issue persisted for weeks, followed by her legs giving way and her vision blurring. Ultimately, her doctor diagnosed her with multiple sclerosis (MS), a condition impacting the brain, spinal cord, and optic nerves.

Eager to understand MS, Nancy searched the Internet for information. She discovered that MS typically affects individuals aged 20 to 40, is more common in women, and has an unknown cause [source: WebMD]. While browsing an obscure forum, she stumbled upon a potential clue: a possible connection between aspartame and MS. She recalled that aspartame was a key ingredient in the diet sodas she had consumed for years.

Although the Multiple Sclerosis Foundation does not claim aspartame—or any additive—is entirely safe, it dismisses the idea that aspartame causes MS. Approved by the U.S. Food and Drug Administration (FDA) in the 1980s for use in carbonated drinks and other foods, aspartame faced scrutiny after consumers reported issues like insomnia and diarrhea. The Centers for Disease Control and Prevention (CDC) investigated but found no evidence linking aspartame to these symptoms or to the onset of MS [source: [url='https://www.msfocusmagazine.org/Magazine/Magazine-Items/Posted/Examining-the-Safety-of-Aspartame.aspxGuthrie[/url']].

The belief that aspartame causes MS likely originated from an alleged firsthand account by an aspartame expert, circulating online and in chain emails since the 1990s. Often credited to "Nancy Merkle," the article lacks citations, and no one has claimed authorship [source: Guthrie].

The FDA Center for Drug Evaluation and Research has debunked claims connecting aspartame to various diseases, including MS. The FDA states that aspartame is among the most rigorously tested food additives, with no evidence supporting a link to MS [source: Hattan]. This is reassuring for Nancy and others who consume diet drinks and low-calorie foods containing aspartame.