Here the opinion piece of Andrew Rawnsley (below an extract focusing on health).
The most risible of the claims made by pro-Olympians is that the Games will inspire the host nation to become fitter. The heavy presence of McDonald's, Coke and Cadbury among the sponsors gives the lie to any notion that the Games are about promoting healthier lifestyles unless you suffer the delusion that a diet of cheeseburgers, liquid sugar and Mars bars will turn you into a rival to Usain Bolt. Studies of previous Games have found no evidence that they improve the host nation's health. Australians are no more sporty since Sydney 2000. The Los Angeles Olympics didn't make Americans thinner.