In June, 2023, a Working Group of 25 scientists from 12 countries met at the International Agency for Research on Cancer (IARC) in Lyon, France, to finalise their evaluation of the carcinogenicity of aspartame, methyleugenol, and isoeugenol. Aspartame was classified as “possibly carcinogenic to humans” (Group 2B) based on “limited” evidence for cancer in humans. There was also “limited” evidence for cancer in experimental animals and “limited” mechanistic evidence. Methyleugenol was classified as “probably carcinogenic to humans” (Group 2A) based on “sufficient” evidence for cancer in experimental animals and “strong” mechanistic evidence, including studies in humanised mice and supported by mechanistic studies in exposed humans.