There's been an uproar lately about the new full-body image scanners being deployed at airports by the Transportation Security Administration. The scanners can generate detailed images of travelers' bodies, raising privacy concerns among some. Critics have also raised questions about the safety of the machines. To learn more about the science behind the scanners, we sat down for a chat with Dr. John Melnick, Medical Director of Lenox Hill Radiology, a ZocDoc-affiliated practice in New York City.

Want to know a scary fact about breast cancer? In its early stages, it typically causes no pain.