Andrew Lansley is half right in thinking the solution to obesity is to eat less and exercise more. The Health Secretary also wants food companies to make leaner versions of their products, to help slash 17 million burgers-worth of calories from daily consumption.

All well and good. But it is not calories alone that make you fat. It is the type of food you eat. Neither tweaks to calorific content, nor the "traffic light" labelling that campaigners call for, nor even the most ambitious exercise regime, can defray the health consequences of eating too much processed food.

There is no doubt that Britain needs a diet: a scales-busting 60 per cent of adults and a third of children are now categorised as either obese or overweight. Mr Lansley's latest strategy is not wrong, just ineffectual. To make a real difference he must take on the food industry.