Scientists are calling for more research on the possibility that some supposedly healthful plant-based antioxidants — including those renowned for their apparent ability to prevent cancer — may actually aggravate or even cause cancer in some individuals. Their recommendation follows a study in which two such antioxidants — quercetin and ferulic acid — appeared to aggravate kidney cancer in severely diabetic laboratory rats. The study appears in ACS' bi-weekly Journal of Agricultural and Food Chemistry. Kuan-Chou Chen, Robert Peng, and colleagues note that vegetables, fruits, and other plant-based foods are rich in antioxidants that appear to fight cancer, diabetes, heart...