A little pill goes a long way

The minuscule matter of 10 milligrams of vitamin B6 is posing big questions about the benefits of supplements and who decides how many we should take.

At first sight it looked like a storm in a muesli bowl. A rather technical dispute about the dose of vitamin B6 that may put you at risk of nerve damage has stirred up trouble in a host of other areas - Labour's commitment to open government, the extent to which Brussels should set standards for us, and the sort of medicine we want in the next century.

It all began last week when Maff, the food ministry, announced that they were planning new legislation to reclassify vitamin B6. At the moment, along with all other vitamins and supplements, it is treated as a food, and you can buy it anywhere in doses up to 200mg. Such high doses are most commonly used to relieve symptoms associated with menstruation, but they are also said to help with problems such as severe acne, epilepsy in children and sickle-cell anaemia.

However, Maff proposes that only doses of 10mg or less should be freely available, packages of 11 to 49 mg should be limited to sale in pharmacies, and anything stronger should need a prescription. This was necessary, they said, because research showed that regularly taking large doses could cause peripheral nerve damage.

The report sparked outrage among various nutritional organisations, which pointed out that people regularly took up to 200mg a day, and that there had been no reported cases of harm from vitamin B6. "Huge amounts of anything can be harmful," says Maurice Hanssen, of the Council for Responsible Nutrition. "100 grams of salt will kill you. But there are many respectable studies showing 200mg is perfectly safe. Why pick on vitamin B6? Why not paracetamol or aspirin, which do actually kill hundreds of people a year?"

What really infuriated them was that one of the key studies quoted by Maff as showing evidence of harmful effects with doses as low as 50mg was not only 10 years old, but was based just on symptoms reported by patients in a series of telephone interviews. "It was a very flawed piece of research, and that was pointed out at the time," says Sue Craft, of Consumers for Health Choice. "Not only have no other studies found harmful effects at that dose, but no one has found the symptoms that were reported - headache, tiredness, depression - even at massive toxic doses of B6."

Linda Lazarides, director of the Society for the Promotion of Nutritional Therapy, says: "Originally Maff wrote to us claiming the toxic dose for dogs was 50mg. We had to point out that the study they were talking about gave dogs 50mg per kilo of body weight - a dose of 3 grams (3,000mg). They then arrived at the safety figure of 10 by dividing 3,000 by 300."

Ironically, one of the effects of this debate about safety levels has been to emphasise the laissez-faire attitude of this country when it comes to vitamin and mineral supplements. In most of Europe, products containing B6, even the new super-cautious level of 10mg, would be outlawed. "The German police regularly raid shops selling vitamins," says John Redman, of the supplement manufacturers Lamberts. "Anything that contains doses higher than the official limit is swept off the shelves." European legal levels, with the exception of the UK and the Netherlands, are calculated at between two and three times the recommended daily allowance (RDA), which in the case of B6 is a tiny 2mcg.

For at least a decade now there have been discussions on how to bring our vitamin regulations into line with Europe. But last week the question reappeared in the form of an EU consultation document entitled "Additions of vitamins and minerals to foods and food supplements", creating speculation that the Maff announcement on B6 may have been designed by the Government to signal a more co-operative line on Europe.

Campaigners here would like to see some sort of Social Chapter-type opt-out so that we don't have to set safety levels as low as double the RDA, which would put the legal limit of, for instance, vitamin C - regularly taken in doses of a gram a day in the UK - at about 150mg.

"In Europe they have a different distribution system anyway," says John Redman. "They already channel all health products through pharmacies. If we are forced to do that, the only people to benefit will be the pharmacists. The consumer will end up paying more, and many small firms and shops will go to the wall."

All this talk of safety levels highlights an even more fundamental issue: is it worth taking supplements at all? There is still disagreement between most nutritionist groups and the medical profession about their value. Traditional GPs are likely to advise patients that vitamin supplements are a waste of time, providing you eat a healthy diet; all they do is give you very expensive urine.

Rubbish, retort the nutritionist campaigners. They point out that the nutritional composition of even fresh fruit and vegetables varies a lot, that all sorts of people don't eat a proper diet, and that the amounts of vitamins and minerals we need varies according to how much stress we are under. From this perspective the RDA - based on the minimum amount needed to avoid harmful deficiencies - becomes irrelevant.

If that is the case, what we should be looking for is optimum nutrition: what are the amounts you need to stay in the best shape possible?

Over the last year the tide has been running in the nutritionists' favour. Several respectable studies have showed, for instance, that high levels of vitamin E supplements protect against heart attack, while the mineral selenium, in doses far in excess of the RDA, helps against cancer. "Nutritional medicine is all about keeping yourself healthy," says Linda Lazarides, "not about waiting to take drugs when things go wrong. If the Government is so keen for people to take more responsibility for their health, why are they proposing a new system that will make it more expensive, and add to the GPs' burden by making them write out unnecessary prescriptions?"

The problem, from a legislative point of view, is that vitamins don't fit easily into a system that classifies what we eat as either a food or a medicine.

At the moment vitamins are classed as food, which is why Maff looks after them. But if something is a food, you can't claim any specific health benefits, such as "B6 - good for relieving painful periods." Once you do that it becomes a medicine, and those come under the Department of Health. To sell a medicine you need a product licence, which costs around pounds 200,000; most vitamin manufacturers don't have that kind of resource. The problem is that this medical arm is designed to deal with drugs, and to prevent tragedies such as thalidomide happening again.

"What we need is a third category that covers vitamins and minerals," says Margaret Peet, managing director of GNC UK, a major health food retailer. "They have it in Australia and the US, so there is already lots of information about the upper safe limits and how much people need for optimum health."

With such big issues lurking behind these small pills, it would seem that what's wanted is some wider debate. But that is precisely what the latest Maff announcement denies. Its B6 reclassification proposal, endorsed by the new Food Safety minister, Jeff Rooker, is based on the findings of the Committee on Toxicity, which meets in secret and is not obliged to give any reasons for its conclusions.

"They can't have properly looked at our evidence," asserts Linda Lazarides. "So many reputable experts have concluded that 100mg to 200mg is a safe range that their finding is just eccentric, but we've no way of knowing how they arrived at it."

Not only that, but there is concern that a committee that was set up to deal with poisons and the side-effects of drugs is possibly not the right group to look at the more subtle balances involved in substances which the body is designed to use, and which are vital to health. A bit less legislation and a bit more open discussion would seem to be a sensible prescription