Jamie Oliver picks a fight with David Beckham over his junk food adverts

Gary Lineker also targeted by chef in campaign for children to eat healthily

The celebrity chef Jamie Oliver has criticised sporting heroes like David Beckham for promoting junk food to children.

Beckham and Gary Lineker are highlighted for criticism in an open letter signed by the celebrity chef and health professionals and teachers.

"On the eve of the London Olympics we, a group with a vested interest in improving the health and well-being of young people, express our grave concern about this trend," the letter published today in The Times newspaper says.

"We believe it is wrong for athletes to encourage the excessive consumption of such items, which are fuelling poor health and obesity. David Beckham is a great sportsman, yet he has endorsed Pepsi. What about the impact of Gary Lineker's association with Walkers crisps? Or the partnership between Mars and the FA?"

The letter, which is also signed by the Royal College of Paediatrics and Child Health (RCPCH) president, Dr Hilary Cass, accuses food companies of triggering a "halo effect" around unhealthy foods by associating them with sport. "With one in three children in Britain overweight or obese by the age of nine, we have a public-health crisis that requires urgent intervention. We would ask athletes to be very conscious of the effect their endorsements may have on the future lives of youngsters. Obesity does not just carry physical consequences but serious social and emotional ones as well."

Other signatories to the letter are the RCPCH past president Terence Stephenson, the National Association of Head Teachers president Steve Iredale, Children's Food Campaign director Charlie Powell and London cardiologist Dr Aseem Malhotra. Dr Malhotra has called for a total ban on junk food sponsorship of the Olympics. He said: "It is totally perverse that some of the main sponsors of the greatest sporting spectacle in the world are McDonald's and Coca-Cola.

"One vital step in reducing the consumption of obesogenic products is to end the association of sporting role models with junk food. The very lucrative financial gain for these athletes is sadly at the expense of our children's health and we should not allow this to continue."

Dr Cass said: "We shouldn't underestimate the fascination that many children and young people have with celebrities, whether that's teenage girls skipping meals to look like the latest airbrushed magazine model or boys wanting the same brand boot as their footballing idol.

"Sporting role models in particular can send a powerful message to children when it comes to their health and fitness. Instead of glamorising junk food, they should be using their influence to inspire children and young people to become tomorrow's top athletes by eating well and leading active lifestyles.

"With celebrity status comes responsibility. So rather than helping to fuel this nation's growing obesity crisis, these stars can play a key role in helping stem it."