On the Mayo Clinic Radio podcast, Dr. Timothy Moynihan, an oncologist at Mayo Clinic, discusses lifestyle and cancer risk. Also on the podcast, Dr. Karthik Balakrishnan, an otolaryngologist at Mayo Clinic, explains how 3-D printing is being used by surgeons to prepare for complex procedures. And Dr. Win-Kuang Shen, a cardiologist at Mayo Clinic, explains why people faint.