WE HUMANS have evolved to fatten ourselves up when food is abundant, so we can make it through the lean times. It is this tendency, the theory goes, that has been our downfall in recent decades as shops and restaurants have filled with cheap, abundant, energy-rich food. Without the lean times, the world westerners inhabit has become “obesogenic” and the outcome is all too obvious: 30 per cent of US adults are obese, and the number who are overweight has tripled in 20 years.
There is no shortage of potential solutions, from raising the price of food to persuading people…
