Charles states the obvious, but culture secretary dithers

I never imagined that Big Macs with a side order of fries featured frequently on the menu at Highgrove. The Prince of Wales has long been an advocate (though hardly a shining example) of greener lifestyles, so it wasn't a total surprise when he declared war on fast food recently, suggesting that McDonald's should be banned.

The prince made the apparently off-the-cuff remark during a visit with the Duchess of Cornwall to Abu Dhabi, where he told a nutritionist that banning junk food was the key to a healthy life.

I can't help suspecting that nutritionists know this already, and that the young children who chose fruit and vegetables for their packed lunches, as the royal couple beamed approvingly, are not entirely typical of schoolchildren around the world.

First time

But sometimes someone has to state the obvious, and not for the first time the British government has been outflanked on a subject on which its own behaviour has been pusillanimous.

The 24-hour availability of burgers and other junk food has been disastrous for the nation's health, but our reliance on ready-made supermarket meals with high levels of salt, sugar and fat isn't far behind.

Yet the British government, in the shape of the Culture Secretary Tessa Jowell, has repeatedly shied away from taking on the food producers and supermarket chains, who prefer voluntary agreements on labelling and advertising junk food to children (now there's a surprise).

Neither have the Tories shown any willingness to risk alienating the Big Mac-eating classes.

Listening to Jowell, you could be forgiven for imagining that the link between health, weight and the food people eat - encouraged by supermarket special offers and advertising - is controversial, complex and hard to understand.

Perhaps she hasn't seen Morgan Spurlock's documentary, Super-Size Me, which demonstrated what happens to the human body when it is overloaded with fat and sugar.

Giving evidence to the House of Commons Health Committee's inquiry into obesity, Jowell repeated her mantra that she wanted to work with the industry to encourage healthy eating.

She also said she believed that advertising did have an impact on what children ate but it was difficult -like the link between eating and obesity, I suppose - to pin down.

No doubt that's why big companies go on pouring money into their advertising budgets, while Jowell scratches her head and the country's children get larger.

Even now, after the regulator, Ofcom, has decided to limit children's exposure to advertising, a battle is still raging over food labelling, with some of the big supermarkets on one side and doctors on the other.

It shouldn't take an intervention by the Prince of Wales to remind us that ministers are prevaricating while a health disaster unfolds.