Before getting bariatric surgery, Los Angeles DJ Big Boy posed for a photo promoting his radio station, Power 106. He weighed more than 500 pounds. Courtesy of Power 106 FM hide caption

itoggle caption Courtesy of Power 106 FM

Water plant operator Torrey Jones checks the clarity of a sample of treated water at the Beaver Falls Municipal Authority water treatment plant in Beaver Falls, Pa. Keith Srakocic/AP hide caption

itoggle caption Keith Srakocic/AP

University of Miami pediatrician Judith L. Schaechter gives an HPV vaccination to a 13-year-old girl last week in Miami. Joe Raedle/Getty Images hide caption

itoggle caption Joe Raedle/Getty Images

Seeds from Golden Rain acacias like these in Wales provide the active ingredient for a pill to help people stop smoking. Tom Patterson/Flickr hide caption

itoggle caption Tom Patterson/Flickr