You really couldn't make it up. A government quango has produced guidance for doctors with the advice that it may be counter-productive to use the term "obese" when talking to patients. And the title of the report? "Obesity: Working with Local Communities".

The report suggests that medical professionals should "carefully consider the type of language" they use to communicate the bad news to a patient that they may be dangerously overweight, or, as the authors would probably have it, a teeny, weeny bit on the heavy side. I spoke to my eminent doctor friend – let's just call him Dr G – about this, and he opposed a mealy-mouthed approach. "Patients don't listen to you anyway when you're telling them they have to modify their lifestyle," he said, "so you might as well kick them in the nuts, so to speak."

It seems to me that the "o"-word has only relatively recently become an issue, largely because more people are actually obese these days, and that, since 1972, doctors use the body mass index (BMI) scale as a prescription for deciding whether someone is overweight or not.

The trouble with BMI – in simple terms, a way of measuring an individual's percentage of fat by dividing body mass by height – is that it is a rather blunt instrument. A rugby player, for instance, might register as morbidly obese because of his muscle mass or bone density.

A much better indication of a person's fat quotient, says Dr G, is to measure waist circumference. And in terms of finding a way to alleviate the strain on the NHS caused by the obesity – sorry, I mean differently sized – epidemic, Dr G says that experts in the field now believe that gastric banding is the most cost-effective and successful way of getting people to change, particularly those most at risk through a mixture of environmental and social factors.

There is also the question of whether we should even be worried about the nomenclature when we are faced by a very serious health issue – if you apply the strict criteria of the BMI index, a quarter of British adults are technically obese, and that figure is projected to double by 2050.

In terms of getting people to take a long, hard look at themselves, I'm not sure that "obese" works better than "fat", given that the former is a medical term, and the latter is a more personal, social descriptor.

Shame is always a good motivation, I find. I always thought that the anti-smoking lobby would be better to focus on the psycho-social effects of cigarettes rather than the serious health aspects.

I'm broadly with Dr G in telling it how it is. The report does say that it's OK for doctors to use any terms among themselves. So now I know why, during my last examination, my doctor wrote "FF" on my case notes.

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