Dean Ornish on 4 Changes That Undo Disease; Do You Really Have a Food Allergy; Truth About Hangover Cures

Who wouldn't want to "undo" conditions like heart disease? WebMD Chief Medical Officer John Whyte, MD, MPH, interviews Dean Ornish, MD, on what changes to make. Then, food allergies vs. intolerances -- we break down the difference. Plus, how to stop a hangover before it starts.