Obese children will be exposed to “positive peer pressure” to encourage them to lose weight under Conservative proposals to make young people take more responsibility for the health.

Andrew Lansley, the Shadow Health Secretary, outlined a “no excuses” approach to childhood obesity, drunkenness, drug-taking and under-age age sex in a speech today.

He also announced that a Tory administration would refuse to implement further advertising bans on junk-foods and scrap so-called traffic-light food labelling.

Instead, the Conservatives have appointed the head of Unilever - whose products include mayonnaise and ice-cream - to develop a new “responsibility deal” with business.

“Tell people that biology and the environment causes obesity and they are offered the one thing we have to avoid: an excuse,” Mr Lansley said.

“As it is, people who see more fat people around them may themselves be more likely to gain weight. Young people who think many of their friends binge-drink are likely to do so themselves. Girls who think their peers engage in early sex are more likely to do so themselves. Peer pressure and social norms are powerful influences on behaviour and they are classic excuses.”

“Our need, and not just in relation to public health issues, is to act on the environment, while fostering positive peer pressure and social norms. We have to take away the excuses.”

Mr Lansley’s speech follows David Cameron’s call for a return to the notion of individual responsibility. “We talk of people being ‘at risk of obesity’ instead of talking about who eat too much and take too little exercise,” the Tory leader said in the land-mark speech last July.

The Conservatives contrast their approach of harnessing social pressure to improve public health with what they claim are overly-bureaucratic methods currently deployed.

Policies like the so-called “traffic light” labelling system that group all foods into three categories are an example of failed Whitehall intervention, they claim.

Dave Lewis, chairman of Unilever UK and Ireland, who has agreed to head a new Tory working group on public health, welcomed the Tory commitment to scrap “traffic light” labelling.

“When it comes to providing clear and accurate nutritional information to help consumers make healthy food choices, the traffic light system is too simplistic.”

Other initiatives to be considered by the working group include voluntary agreements to re-formulate popular brands to include less fat and salt and to decrease portion sizes.

A proposal to require a proportion of alcohol advertising to be spent on the promotion of responsible drinking will also be considered.

Ann Keen, Health Minister, said: “Once again the Tories offer lots of warm words but with very little policy substance.

“Everyone believes that individual responsibility matters. But the Tories are using individual responsibility as an excuse for their lack of effective policies in this area.”

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