Food labels alone will do nothing to stop the obesity crisis - people just need to stop making excuses for not eating a balanced diet

Ihave disliked John Humphrys for years - ever since he hosted an event for the National Federation of Meat and Food Traders and said he wouldn't read the script I had written because he was "from the BBC" and "had to be impartial"... and then read it out anyway. And especially since he wrote The Great Food Gamble, with its chapter on aquaculture which, according to Scottish Quality Salmon, had more than 50 errors.

These days on the Today programme he usually seems to be going through the motions - a professional antagonist, contrary for the sake of it, regardless of the merits of the story.

Until a week ago, when health secretary Alan Johnson popped up to talk about the need for a consensus on food labelling. Traffic lights versus GDAs. Suddenly, in stating the bleeding obvious, Humphrys said something quite profound. "We know what makes us fat," he contended on behalf of the British public. "And if we don't know by now we are stupid."

Johnson seemed to take objection to this. Surely all the effort and argument that has surrounded nutritional labelling couldn't just be for the benefit of stupid people? But Humphrys was right. There can be no excuse for not knowing what makes a balanced diet, and the solution is in our own hands. There is enough information already available to achieve this. Except, of course, for the stupid people. And possibly Daily Mail readers whose nutritional advice comes from some sort of parallel universe.

That's why nutritional labels have to aim for the lowest common denominator in understandability - and why the latest labelling initiatives are doomed. The traffic light system is clearly designed for stupid people. Unfortunately though, for many of its targets, green means go, amber means go faster and red means don't get caught. Flippant, but early research indicates traffic light labelling has had little effect on shopping behaviour.

Guideline daily amounts fail this audience because they include numbers, and numbers are difficult, especially for the rising percentage of the population that can't muster a GCSE in maths. So, the dim will ignore traffic lights because they see them as irrelevant and GDAs because they are complicated.

The intelligent see traffic lights as absurdly simplistic (honey, red? Surely some mistake?) and GDAs as applying to somebody else - the supposedly 'average' person who doesn't exist, and they can work it out from the nutrition panel on the back anyway.

Maybe the new cookery education in school initiative will solve everything. Compulsory cookery for all 11 to 14-year-olds sounds like a good idea, but isn't that about eight years too late for most children? Shouldn't they be exploring food from the earliest possible age? Meals as a social occasion, food as fantastic, not fuel, and hands in the mixing bowl and full engagement with where food comes from. Waiting until the age of 11 to explain that carrots don't grow on trees seems a lost opportunity.

The love of food starts at home and if it is absent it must be reinforced in nurseries, primary and junior schools. Until we again become the food-literate nation we once were, able to make reasoned choices based on our own individual needs, likes and dislikes, we are doomed to increasing obesity.

Labels alone add nothing. And for the time being, a good proportion of the population is going to remain stuffed.n

Rob Metcalfe, MD, Richmond Towers