But the biggest plus for health would be the reductions in obesity, diabetes, and cardiovascular disease that they said would follow a decrease in sugar consumption. Among the speakers was Steven Gortmaker, a Harvard public health researcher, who projected last month that the tax would eventually prevent 36,000 cases of obesity a year and 730 deaths over a decade in Philadelphia. He said it would drive down sugar intake in much the same way that tobacco taxes, along with changing attitudes, drove down smoking rates and, with them, cancer.