JUNK food really concerns me because mankind could unwittingly be going the way of the dinosaurs. That’s why I’m supporting TV chef Jamie Oliver. Let me explain: The great advances in medicine, nutrition and hygiene we’ve enjoyed over the past 100 years or so should mean we’re all living longer because we’re much healthier.

But are we actually killing ourselves with a toxic combination of junk food, sugary drinks, too much TV and not enough exercise?

Today’s generation of children could be the first in history that doesn’t outlive its parents and the reason is simple: we let them eat and drink the wrong things – junk food – and then we allow them to become couch potatoes.

And that’s why I’m whole-heartedly supporting applaud Jamie Oliver’s Food Revolution Day, on May 16 when he aims to set a world record for the greatest number of people cooking the same dish on the same day – a very healthy sounding Rainbow wrap, a slaw with feta cheese wrapped in flatbread.

Research in Finland has highlighted the dangers our children face: by studying 468 children between the ages of six and eight a proven link was established between low levels of physical activity and an increased risk of diabetes, heart disease or strokes.

Watching TV and videos instead of running around outside or playing an organised sport directly increased the chance of life-threatening illness. Bigger waistlines, a higher percentage of body fat, higher blood pressure, higher cholesterol, higher blood sugar levels…the list of health problems was scary and endless.

In the United States, the land of junk food, childhood obesity has more than doubled in children and quadrupled in adults over the past 30 years. In Britain, almost a third of 10 and 11-year-olds and over a fifth of four to five-year-olds are either overweight or obese. This week, it was revealed that one patient in seven in Britain’s NHS hospitals has diabetes.

The warning signs could not be any clearer. The trouble is, who’s listening?

TV chef Jamie seems like a voice in the wilderness when he calls for the appointment of a “political visionary” to put childhood obesity at the centre of next year’s general election campaign.

 “You can’t have one arm of the Government investing money in food education and school lunches and then have another part promoting junk food, en masse, to be licensed and given permission to trade within a stone’s throw of a school,” he says.

Public Health England has just brought out tough new guidance for councils, urging planners to refuse permission for burger bars, chip shops and pizza parlours within five minutes’ walking distance of schools.

Officials are worried that secondary school children, many of whom are allowed to leave school premises at lunch time, are unable to resist the temptation to snack on junk food if it is available nearby.

Jamie famously pushed healthier school dinners up the political agenda during the 2005 agenda but he recognises that he still has a massive fight on his hands. “There is not one country on the planet which has smashed the obesity crisis,” he says despairingly, “not one country where obesity levels are coming down.

He believes 50 or 60 decisions and initiatives need to happen at once followed by a five-year strategy to improve eating habits. Jamie has declared May 16 to Food Revolution Day and he’ll broadcasting cooking class for children across the globe via his own TV channel.

 “Getting kids cooking from as early as possible helps them to develop an essential life skill which will have a huge impact on their future health and wellbeing,” he says.

Will any politicians grasp the nettle? The Labour party is reported to be in favour of banning TV adverts for sugary breakfast cereals until after the so-called 9pm watershed but when has banning anything ever worked? We know from our work at ThinkingSlimmer.com that unconscious persuasion is a far more effective way of influencing behavioural change than a dictatorial approach.

Nudging children towards a healthier lifestyle and away from junk food requires a carrot not a big stick. In fact, two carrots would be even healthier.

* A version of this blog by Sandra recently appeared on the Huffington Post.