As a scourge of the modern society, obesity has become the world’s biggest public-health issue today — the main cause of heart disease, which kills more people these days thanAIDS, malaria, war. Since the World Health Organization labeled obesity an "epidemic" in 2000, reports on its fearful consequences have come thick and fast. Will public-health warnings, combined with media pressure, persuade people to get thinner, just as they finally put them off tobacco Possibly. In the rich world, sales of healthier foods are booming and new figures suggest that over the past yearAmericans got very slightly thinner for the first time in recorded history.But even ifAmericans are losing a few ounces, it will be many years before the country solves the health problems caused by half a century’s dining to excess.And, everywhere else in the world, people are still piling on the pounds. That’s why there is now a consensus among doctors that governments should do something to stop them.