I genuinely believe that the food we eat is a greater cause of obesity than inactivity. In the 'olden days' people didn't have a wide range of tasty, calorie-packed treat food paraded in front of them 24 hours a day, and they probably couldn't have afforded to eat it very often even if they had.
Willpower is of course the ultimate solution, but nowadays your average Briton needs much more willpower than his grandad did in the 60s.
