Obesity has reached epidemic proportions. Just check out the growth spurt of one of Europe’s most popular hatchbacks, the VW Golf:

Model (1.4 3dr) Length (mm) Weight (kg)
Mk1 3721 780
Mk2 3985 930
Mk3 4020 960
Mk4 4149 1163
Mk5 4204 1230

Most mainstream modern cars are fatter than 20 years ago thanks to extra equipment, the need for more space and I’ve-got-more-airbags-than-you one-upmanship.

“Vehicles are getting heavier because of the equipment being added,” says Peter Cooke, professor of automotive industry management at Nottingham Trent University.

“Air-conditioning and safety kit all adds up, and each new regulation brings more weight, yet the lawmakers also want more economical, environmentally-friendly vehicles. Something’s got to give.”

Unnecessary flab – that’s what’s going to give. Manufacturers are fast realising that developing clever new propulsion systems and clean fuels are the most costly and slowest ways to save the world.

“Sending cars on a crash diet is a win-win situation. Lighter cars are not only cleaner, they’re cheaper, quicker and better handling, too.

Prof Cooke is convinced that weight will be designed out of cars at the drawing board stage. Better design, and more widespread use of lightweight materials, will help make the cars of tomorrow cleaner and greener.

And we’re starting to see the fruits of the Weight Watchers programme now. The new Mazda 2, for example, is 40mm shorter and 100kg lighter than its predecessor. Result? A 15% drop in fuel consumption.