Three years of effort against a background of growing childhood obesity have finally brought us to the point at which Whitehall is prepared to tell some parents that their children are fat.

But so anxious is the Government not to be seen as a nanny that it has bent over backwards to avoid any risk of offence. Are parents and children really so sensitive that they cannot face the word obese, or so innumerate that the concept of body mass index is beyond them?

The risk of soft-pedalling an issue as potentially dangerous as this is that the message will fail to reach those most in need of it. As is so often the case in health education campaigns, those who read the letters and act on them will be the conscientious.

Those who toss them in the bin unread will be the poor and the poorly educated. Inequalities of health will widen, and the Government will wring its hands in despair.

Parents, of course, have the right to bring up their children any way they like, and that includes badly. But if you take this hands-off attitude - in many ways an admirable one - you cannot at the same time agonise about its consequences. The Department of Health is trying to have it both ways, claiming that it knows what weight is best for the nation’s children but then retreating from the implications of such a claim. The result is a policy that pleases nobody, and smacks of compromise and a desperate fear of giving offence.

In its defence, it can be argued that monitoring children’s weight is far from an exact science. Children are still growing, and at different rates, so age-adjusted charts need to be used to determine whether their BMIs are in the healthy or unhealthy range.

Some experts now argue that waist circumference is a better measure. But for the moment the programme has opted for BMI – though its letters to parents do not actually say so.

Question marks still hang over the programme because of the opt-out clause that enables parents to exclude their children from weighing and measuring. The department has failed to explain why, apart from citing human rights legislation.

Data gathered so far needs a safety warning. But it shows, on an 80 per cent sample, that 22.9 per cent of four and five-year-olds and 31.6 per cent of ten and eleven-year-olds are overweight or obese. In both age groups, boys are more likely to be overweight than girls.

The chances are that even these alarming figures underestimate the extent of the problem, because the opt-out means that the heaviest children are the least likely to be weighed.

It would also be wrong to judge the programme in isolation. Restrictions on advertising, the healthy food initiative in schools and the encouragement of school sport are other initiatives aimed at the same outcome.

It is impossible to argue that the Government isn’t trying. But at the same time, its efforts appear puny compared with the scale of the problem. And its fear of giving offence implies that whatever it may say, it is not yet ready for a red-blooded commitment.

Hanged if it does, and hanged if it doesn’t, seem to be the watchwords.

Times Recommends

• In the real world, the public sector must pay
• Playing politics in a land of double Dutch
• Be like the plinth people: not set in stone