Ever wished you could wash down that pizza, cheesecake and beer with a magic pill to make it all vanish from your waistline? The prospect may be only a few years away, say Australian scientists doing research on a drug to simulate the effect of exercise, a move sure to excite couch potatoes the world over. “I’ve loosely called it the vanity drug,” said Bruce Kemp, senior research fellow at St Vincent’s Institute of Medical Research in Melbourne.