Does aspartame cause adverse health effects?

No. The overwhelming body of scientific evidence clearly demonstrates that aspartame, even in amounts many times what people typically consume, is safe and not associated with adverse health effects. The FDA has investigated alleged complaints since 1982 and states that there is no "reasonable evidence of possible public health harm" and "no consistent or unique patterns of symptoms reported with respect to aspartame that can be causally linked to its use."

In 1984, the FDA commissioned the Centers for Disease Control (CDC) to review complaints which some consumers related to their use of aspartame. After a review of 517 complaints, the CDC found that the complaints "do not provide evidence of the existence of serious, widespread, adverse health consequences attendant to the use of aspartame." The CDC further noted, "the majority of frequently reported symptoms were mild and are symptoms that are common in the general populace."

In response to these complaints, numerous additional scientific studies were done after marketing by prominent researchers at major academic institutions; the results of these studies overwhelmingly demonstrated that aspartame is not associated with adverse health effects, including headaches, seizures, changes in mood, cognition, behavior or allergic reactions.