I am one of the 12 million. I am one of those who each morning, line up a row of assorted tablets to supplement my diet. I even have one of those dinky little boxes with a compartment for each day's dose: it goes with me wherever I go, pops up on hotel breakfast tables, at railway buffets and at the homes of startled friends with whom I am spending the weekend. I explain I am trying to do myself a favour by staying fit as I get older. They can now flourish threatening headlines in my face and tell me I may be shortening my life. You just can't win.

Researchers at Copenhagen University have condensed the findings of 67 studies of some 230,000 healthy people and concluded that high doses of vitamin A supplement can increase the risk of death by 16 per cent, vitamin E by 4 per cent. Beta-carotene was linked to a 7 per cent increase in risk. That's not all: calcium in excess can build up in the liver. And there's no proof that lots of vitamin C helps ward off a cold. You just can't do right for doing wrong, can you?

It's always been assumed, by me among many others, that vitamins were the good guys. I had aunts and uncles who grew up with too few in their diet who then developed rickets that left them bow-legged for life. And whereas 'eat your greens' has always struck misery in the heart of every child, there was a time when the free distribution of cod liver oil and concentrated orange juice helped lift a generation of children from the poor diets that their parents knew.

From then on vitamins were the brave fighters against infection. Surely you couldn't have too much of a good thing? Now it appears you can.

There are certain issues that have to be dealt with. First, the five doses (sorry, portions) of fruit and vegetables per day are just not sustainable. There is only so much spinach and stewed rhubarb the body can stand.

Either we eat this stuff raw, which means cold, and forego the comfort of warm food entirely. Or we spend time making plain vegetables palatable with time-consuming recipes that will almost inevitably involve creamy sauces and butter. How much more healthy is that? Besides, many of us take lunch in canteens and cafes, pubs and even on the hoof. Five fruit and veg are not going to make it big in such surroundings. The temptations are too strong, the menus too full of mouth-watering gloop that tastes scrumptious and kills you too.

Stopping off at a coffee stall before I catch a train, I just occasionally take the option of an apple, lurking unloved in a basket alongside the pastries, sausage-rolls and pain au chocolat. I have never seen anyone else do the same. At best someone might opt for a banana, currently the trendiest gesture towards healthy living. So government agencies and health pundits are wasting their time. We've heard the message and we're not voting for it.

Then again, to each his own. We pill-poppers select the particular needs that help our individual condition. I take cod liver oil, glucosamine sulphate, folic acid and a single multivit tablet. The medical condition I am treating is that of old age, the symptoms creaking and stiffening limbs, loss of energy, and a memory that increasingly forgets names and even facts. I have no control mechanism to tell me what I would be like without my daily intake, so I reckon that I might as well give it the benefit of the doubt. What's to lose, except the cost of pills that might be having no effect at all?

On the other hand, we all know the pharmacist's shelves are stacked with little bottles and a multitude of trade labels.

We in Britain swallow £220m worth of pills a year, and there's a booming pharmacology industry out to exploit our human weakness, play on our fears and in the end disappoint our hopes. You can't live for ever. What's more, the internet is dense with offers of stuff that can work miracles. I, teasingly, am regularly targeted with Viagra offers! I know there are people with anxiety levels so high that they scour the net for other ways to fend off their fantasy nightmares by ingesting chemical compounds.

People who are neurotically hypochondriac will be easy targets for unscrupulous salesmen. I am with the Department of Health in trying to warn them of such risks. Excess in all things is bad. But until we are told of dose limits with exact and scientifically-quantified dangers then simply railing vaguely against vitamin excess is pointless. Don't they know that we in the West live in times of excess!

joan.bakewell@virgin.net