We crave unhealthy foods because they contain lots of sugar and artificial additives, which taste delicious, and therefore trigger the release of certain pleasure-inducing neurotransmitters. Furthermore, we are evolutionarily programmed...

Smoking rates are falling in the UK, US and much of Europe. Forty-five per cent of Brits smoked in the 60s and 70s, compared with just 15% today. You would think this was bad news for cigarette profits, but tobacco companies are making...