Fashions change in medical care as surely as they do in Paris or Milan, even if more slowly. Sixty years ago doctors struggled to make certain that their sickliest and most deprived patients had fresh butter, cheddar and full-fat milk.

When I joined my first practice in a rural part of Norfolk I was intrigued by the hampers that my senior partner prepared each day for selected patients. Some were sent only eggs, others had eggs and cream, and occasionally a chicken would be included.

I soon realised that there were two qualifications for this care. One group was included because of genuine poverty and my partner’s kindliness. The others were given what were then considered nourishing luxuries as a placatory gesture because often, I fear, my colleagues’ previous medical advice had been a bit weak.

This was a time when chicken drumsticks would have been a treat for Sunday lunch, and not the means by which the Treasury could further increase its revenue from indirect taxation. The proposed “fat tax” will be a tax on human frailty, collected from the overworked who have neither time nor money to prepare the well-organised, decent meals of a more leisurely age.

From time to time, surveys are commissioned to find out where the public derive their medical information from and the credence they give to various sources. More people still rely on the primary-care team of GP, practice nurses and the local pharmacist than any other source.

The press, both daily papers and magazines, run them a close second. Departmental handouts fare badly and are not given the credence they sometimes deserve. The last one on diet, for instance, was excellent. But there is always the suspicion that Government-sponsored information has been influenced by the Treasury or politicians, to garner taxes or votes. And indeed, too often the advice has later been shown to be wrong.

Treasury interference in medicine is always especially suspect. Patients, as well as doctors, like to believe that the medical evidence with which they are presented has not been tainted by political slant or fiscal motivation.

The problems with obesity, particularly in children, are too important to allow the issue to be confused by introducing taxation as another factor in the debate. Any suggestion of taxation will also add to claims that central government is becoming the all-powerful nanny. People need to be encouraged to return to a better-balanced diet rather than fined for not allowing the Government to control their cooking and family meals.

Eggs, cream, chicken legs, pork pies and chips in excess can be damaging to people who put on weight readily, have the potential to suffer from hyperlipidaemia, or have a family history of diabetes or obesity. Others could happily tolerate a diet rich in those nutrients (which were, after all, once considered lifepreserving).

The Norfolk or New Zealand farmer who worked all hours and ate calorie-dense foods was able to live to old age without becoming atherosclerotic or fat because the rest of his lifestyle was geared to it. Not only does the correct diet need to be balanced, so does the lifestyle.

We need less fat — or, rather, some of us do — less salt and more exercise to balance today’s sedentary and pressurised life, in which there is neither time to stand and stare nor to serve the traditional meal of meat and vegetables, cheese and fruit, together with milk, and to group the family around a formally set table.

Balance is all, and everyone needs a certain amount of fat. It has an important part to play in nutrition, it makes our food palatable, and it ensures that we absorb the correct vitamins.