Catherine Carstairs, a history professor at the University of Guelph, delves into the evolving attitudes towards fluoride and its impact on oral health and social inequality. She discusses the controversial legacy of fluoride use in public health, highlighting both its cavity-reducing benefits and the health concerns raised over the years. Along with insights from Oliver Jones, a chemistry professor, they explore public fears about fluoride in drinking water, including debates over IQ impacts and regulatory challenges in communities.