Quitting is so hard

SOLVING some of the world’s great health problems, such as cancer and Alzheimer’s disease, remains beyond the wit of science. Not smoking. For over a decade, it has been clear what countries need to do to get people to quit. Yet although rates continue to fall in some countries—such as America and Britain—elsewhere they are rising. That’s true not just in the poor world, where people are getting prosperous enough to take up the habit, but also in bits of the rich world: on some measures rates are plateauing in Germany, France, Belgium and Portugal after decades of decline. It is time to push them down.