Joan Smith: Fat and sugar kill. And a good government says so, loudly

Defending the nanny state that keeps its people alive

Another year, another anti-obesity campaign: this time the Government's annoyingly named Change4Life strategy. The centrepiece of the latest campaign is a series of TV adverts, made by the team behind Wallace & Gromit, which shows cartoon characters gradually becoming flabbier as they leave the Stone Age and adapt to a sedentary modern lifestyle.

It's a neat idea, but the Government has been telling us about the dangers of eating too much for the past decade. The result has hardly been a triumph for public health campaigns: one in four children arrives at primary school overweight, and it's one in three by the time they leave. If people go on getting fatter at this rate, 90 per cent of children will be overweight by 2050, putting them at risk of diabetes, cancer and heart disease. Yet only 6 per cent of the population has got the message about excess weight and ill health, according to the Government's chief medical officer, Sir Liam Donaldson. So I can't help wondering when the Government will stop pussyfooting about and go for drastic measures.

Yes, I am talking about regulation. Persuading people to lead a healthier lifestyle is incredibly difficult; if you're used to eating as much as you like and taking no exercise, getting fit is harder than learning a new language. Most people with a weight problem need to eat a hell of a lot less than they do now, put up with endless complaints from their children and walk everywhere instead of using the car.

The idea that you can achieve all that by showing people a few adverts is preposterous, as is the Government's notion of treating food producers and supermarkets as "partners". This isn't how the Government approached cigarette manufacturers, who happily went on selling their lethal products to as many people as possible until ministers forced them to display graphic warnings. Children can't buy cigarettes and now adults can't smoke in public places, all of which shows what governments can achieve when they find the will. Yet anyone can walk into a supermarket or corner shop and buy endless quantities of sweets, crisps and fizzy drinks; they're even on sale in hospitals, where it's often easier to get a can of Coca-Cola or fizzy orange than a bottle of water.

If the Government was proposing to get equally tough with the food industry, I'd be delighted. I'm sure it could come up with a logo – a skull and crossbones maybe – to press home the message that obesity is a killer. Instead, ministers allow food producers and supermarkets to get away with minor concessions, such as nutritional labelling which certainly can't be described as user-friendly. One of the advantages of sticking to a low-fat diet is that there are entire sections of big food shops that you don't need to go into, which makes up for the time lost reading the small print on the back of a soup carton.

Obesity reduces life expectancy by nine years, and 11 years for the severely obese. By 2050 it will cost the country £50bn – half the annual NHS budget – if current trends continue. The Government's response is to launch yet another public awareness campaign, rebrand the London Marathon, and let the food industry go on selling as much rubbish as it likes. Crisis? What obesity crisis?