FDA Says Aspartame Is Safe, Disagreeing With WHO’s Cancer Link

The U.S. Food and Drug Administration (FDA) disagrees with the World Health Organization’s recent assessment that aspartame possibly causes cancer in humans. “Aspartame is one of the most studied food additives in the human food supply. FDA scientists do not have safety concerns when aspartame is used under the approved conditions,” an agency spokesperson said. The International Agency for Research on Cancer, a WHO body, found a possible link between aspartame and a type of liver cancer called hepatocellular carcinoma after reviewing three large human studies in the U.S. and Europe. Dr. Mary Schubauer-Berigan, a senior official at IARC, emphasized that the WHO classification of aspartame as a possible carcinogen is based on limited evidence. Schubauer-Berigan acknowledged during a news conference with journalists Wednesday that the studies could contain flaws that skewed the results. She said the classification should be viewed as a call to conduct more research into whether aspartame can cause cancer in humans. “This shouldn’t really be taken as a direct statement that indicates that there is a known cancer hazard from consuming aspartame,” Schubauer-Berigan said.

The FDA spokesperson said the classification of aspartame as “possibly carcinogenic to humans” does not mean the sugar substitute is actually linked to cancer. Health Canada and the European Food Safety Authority have also concluded that aspartame is safe at the current permitted levels, the spokesperson said. A separate body of international scientists called the Joint Expert Committee on Food Additives said Thursday that the evidence of an association between aspartame and cancer in humans is not convincing. JECFA is an international group made up of scientists from the WHO and the U.N. Food and Agriculture Organization. JECFA makes recommendations about how much of a product people can safely consume. The organization maintained its recommendation that it is safe for a person to consume 40 milligrams of aspartame per kilogram of body weight daily during their lifetime. An adult who weighs 70 kilograms, or 154 pounds, would have to drink more than nine to 14 cans of aspartame-containing soda daily to exceed the limit and potentially face health risks.

The U.S. Health and Human Services Department told the WHO in an August 2022 letter that JECFA is better suited to provide public health recommendations about the safety of aspartame in food. This is because JECFA reviews all available data, both public and private proprietary information, whereas the IARC only looks at public data. “Thus, an IARC review of aspartame, by comparison, would be incomplete and its conclusion could be confusing to consumers,” Mara Burr, who heads the HHS office of multilateral relations, wrote in the letter. The FDA has a slightly higher recommendation than JECFA and says it is safe for a person to consume 50 milligrams of aspartame per kilogram of body weight daily during their lifetime. A person who weighs 132 pounds would have to consume 75 packets of aspartame per day to reach this limit.