Press Releases

American Cancer Society Statement: WHO Classifies Artificial Sweetener Aspartame Possible Carcinogen
Jul 13, 2023
Statement from American Cancer Society and ACS Chief Scientific Officer Dr. William Dahut

ATLANTA, July 13, 2023 Today, the International Agency for Research on Cancer (IARC), the research arm of the World Health Organization (WHO), classified aspartame as a possible carcinogen to humans. One of the world’s most common artificial sweeteners widely used since the 1980s, aspartame can be found in foods and beverages, such as diet soda, breakfast cereals, chewing gum, and ice cream, as well as in medications, such as cough drops, and other products like toothpaste. The IARC has four different levels of classification for carcinogenicity - carcinogenic, probably carcinogenic, possibly carcinogenic, and not classifiable. The levels are based on the strength of the evidence. The agency’s assessment lists aspartame in Group 2B – a possible carcinogen to humans.

“The American Cancer Society has always looked to respected lead agencies and organizations to determine whether human exposures cause cancer,” said Dr. William Dahut, chief scientific officer at the American Cancer Society. “The science is still evolving, but we recommend people use today’s report by IARC as a time to reflect on their use of aspartame, but also an opportunity to review their overall dietary intake, including processed meat and alcohol, known carcinogens associated with increased risk of cancer.”

The Joint Expert Committee on Food Additives (JECFA) report also re-evaluated aspartame as a food additive and reaffirmed their established acceptable daily intake of 0–40 mg/kg body weight for aspartame. For a person weighing 70-kg (approx. 150 pounds), this is equivalent to up to 9-14 cans of a diet beverage. For people who want to avoid or reduce the use of aspartame, the ACS recommends checking the ingredient labels before buying or consuming foods or drinks containing the sweetener.

“The American Cancer Society supports the IARC’s call for more research of aspartame and other artificial sweeteners,” added Dahut. “We continue to conduct our own studies to better understand their possible association with cancer and help decrease cancer risk and improve prevention efforts and care.”

ACS scientist Marjorie McCullough participated in the IARC Monographs meeting in Lyon, France last month, serving on the panel of experts to evaluate the health effects of aspartame consumption.

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About the American Cancer Society
The American Cancer Society is a leading cancer-fighting organization with a vision to end cancer as we know it, for everyone. For more than 100 years, we have been improving the lives of people with cancer and their families as the only organization combating cancer through advocacy, research, and patient support. We are committed to ensuring everyone has an opportunity to prevent, detect, treat, and survive cancer. To learn more, visit or call our 24/7 helpline at 1-800-227-2345. Connect with us on FacebookTwitter, and Instagram.

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