Health initiatives target obesity

Among the schemes being trialled in the £30 million Healthy Towns programme is a loyalty card allowing individuals to earn points by buying healthy food and taking part in exercise which can be redeemed for free sportswear or games equipment.

Other ideas include redesigning town centres to encourage walking and cycling, a grow-your-own fruit and vegetable scheme for social housing tenants, urban gardens in areas hit by last year's floods and a "cycle-recycle" project to help people learn to ride and look after their bikes.

Action will be taken to make parks more attractive places to visit, and safe "active travel corridors" will be created to link people's homes with "health hubs".

The Government-commissioned Foresight report, published last year, warned that unless action is taken, nine out of 10 British adults and two-thirds of children will be overweight or obese by the year 2050.

This would impose an additional £50 billion burden on the NHS and the economy, lead to huge increases in conditions such as cancer, heart disease and diabetes and knock nine years off the average Briton's life expectancy, warned Mr Johnson. Even now, 9,000 Britons die prematurely each year due to their weight and a third of 10 and 11 year-olds are overweight, he said.

Mr Johnson told BBC1's Politics Show: "Any government seeing that would be irresponsible just to say we are going to just let things roll."

The Healthy Towns initiative is part of a wider £372 million project to encourage healthier living, drawing on the example of areas in France and Finland which have achieved significant improvements through innovative schemes.

Tuesday will see the unveiling of the Change4Life "lifestyle revolution" scheme which aims to help parents ensure their families "eat well, move more and live longer".

The Change4Life programme will involve community groups, supermarkets, the media and charities in efforts to help every Briton eat more healthily and be more active. Among initiatives under the banner will be cut-price promotions on fruit and vegetables at one supermarket and breakfast clubs in deprived areas funded by a national company.