I trained myself ages ago to tune out the medical scare stories because they make daily life so much more complicated than it is already. Take the most recent dispatches from the outer reaches of nutty science produced by yet more teams of researchers who seem to have nothing better to do with their funding than blind us with epidemiology.

One sausage a day will give you bowel cancer. A cup of coffee a day will stave off Alzheimer’s. Smoking a packet of fags a day and drinking more than two units a day (say one glass of wine while listening to The Archers) can accelerate Alzheimer’s by four years. Drinking wine can increase the risk of breast cancer. Drinking one to three units a day can lower the risk of dementia by 42%.

Oh, I forgot the one I’m supposed to be writing about – vitamins aren’t good for you after all. Popping vitamins, however expensive and horse-pill-sized, does not after all make you beautiful on the inside for longer than nature intended. In fact, taking them every day may even shorten your life expectancy.

Mmm. That made me worried. I have a shoebox in the kitchen stuffed full of omega oil (to make me clever), echinacea (to fend off colds), evening primrose oil (to make me less crabby at my time of the month), leg vein health pills (for my funny leg), vitamin B complex (for “good health and vitality” it says on the bottle), ginkgo biloba (for my poor circulation), and a big bottle of supplements my husband bought me for the “symptomatic relief of tenseness and irritability”. Thanks, darling.

So should I now chuck out the lot on the grounds that, far from doing nothing much to help my little aches and pains, they are actively doing me harm?

Well, let’s look at what the gloomy Danish scientists conclude after crunching down 67 studies of 230,000 people who take vitamins. The review, by the Cochrane Collaboration, found supplements of vitamin A, vitamin E and beta-carotene are bad for you. In 47 trials with 180,938 people, the “antioxidant supplements significantly increased mortality” – in other words, you have a higher chance of dying if you take them. Vitamin A was linked to a 16% increased risk of dying, beta-carotene to a 7% increased risk and vitamin E to a 4% increased risk. Taking vitamin C or selenium didn’t seem either to prolong or to diminish life.

Now it has always seemed to me that vitamins are unlikely to do you any good, as the body only needs tiny trace amounts of them. As a result, if you put any extra into your system, the body excretes it very efficiently (which is probably what happens to most of those expensive vitamin pills that we put in our mouths).

After all, there’s probably enough vitamin C for your whole day’s intake in one chip and vitamin deficiency is almost unknown in this country. So I used to buy vitamins on the same grounds that I buy expensive face creams: they are unlikely to do what they say on the tin, but I am as happy to fritter my money away on false claims as the next ageing, vain hypochondriac – which is why the vitamin industry is worth £220m a year.

So after reading this report, should we stop taking them? Well, yes. Not only are they a waste of money but they could actually make your time on earth shorter. Professor Steve Field, head of the Royal College of General Practitioners, says the public should take good note of the findings, but also that consumers have been gulled for too long by manufacturers’ claims and that in our thirst for eternal youth and health we forget that “the things being sold are not necessarily needed or good for you”.

Obviously pregnant women should keep taking folic acid and I should keep taking my happy pills at the difficult time of the month, but we seem – unbelievably – to have reached a consensus.

“We advise against the use of high-dose supplements. Most people are able to meet their nutritional needs by eating a balanced, varied diet including plenty of fruit and vegetables,” the Department of Health says.

It’s bad news for vitamin manufacturers – but think of the money we’ll save. We can spend it on a nice double espresso to stave off Alzheimer’s instead.

My youngest came to me sobbing. “Mummy,” he wailed, “there’s something in my tooth” (this was in the Easter holidays during which he had eaten a Revels egg and Lindt bunnies, plus a giant Cadbury Creme egg pregnant with half a dozen Creme eggs of its own).

“Let’s see, darling,” I said. I looked into his mouth and could instantly see there was indeed something in his tooth: a great big hole.

I grabbed the telephone directory and called the only dentist for miles around, in Dulverton. I explained I had a child in agony – it’s always good to amp it up in these moments of crisis – omitting to mention meanwhile the Eastertide orgy of chocolate scoffing. There was silence at the other end as she waited for me to finish, a silence that didn’t bode well for my hopes for an immediate appointment, preferably before lunch.

Then she broke it to me. “I’m afraid we can’t see Oliver,” she explained, “ever.” There was stuff about the list being closed to new patients and a dentist on holiday. Finally she said in tones of finality: “I think there’s a private place in Taunton. If you hold on, I’ll give you the number.”

As I was mentally consigning the last day of the holiday to being in the car with a son, moaning, a vision of our prime minister suddenly came unbidden to mind. To be precise, a vision of Gordon Brown addressing his US public on American Idol. In the clip, every time he does that dying-grouper thing with his mouth, or smiles at the wrong moment, it’s as if his new shining teeth leap out of the screen like white lasers.

It takes quite a lot to make me lose my temper (parking tickets and getting lost, mainly). But the fact that GB had just had his teeth cosmetically enhanced when half the population, according to a report last week, haven’t seen a dentist for two years and my own son was in pain was too much to bear.

As Gordon knows, it’s not good enough these days to unleash on your unsuspecting audience a dingy yellow mouthful of what the Americans still call “English teeth”. Now, as all those places offering adult braces and lunchtime whitening remind us, every Brit is expected to unveil gnashers of dazzling luminosity and orthodontic correctness.

Gordon Brown had access, as a child in Scotland, to some dental care at least and as an adult has no doubt paid top whack for some cosmetic dentistry. Is it too much to expect the state to provide the occasional filling, in an emergency, for good taxpayers’ children?

Clearly it is.

rachel.johnson@sunday-times.co.uk

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