Six O'clock News report on Vitamin B6

Acting on advice from an expert Department of Health committee that an excess could damage the nervous system, the government had planned to limit the daily dosage of vitamin B6 in food supplements on free sale to 10 milligrammes or under.

But the Agriculture Committee has called for the proposals to be dropped, and for a voluntary limit of 100mg per daily dose to be introduced instead, subject to the findings of the Expert Group on Vitamins and Minerals set up last year by the government to review the supplement industry.

Peter Luff's committee rejected government proposals

The Agriculture Committee, chaired by Tory MP Peter Luff, also recommends that all dietary supplements containing B6 should display a clear warning that intake above 100mg a day may carry health risks, particularly when taken over an extended period.

Mr Luff said: "The committee was very unimpressed by the quality of the science which underlay the recommendation by ministers.

"There was an over-reliance on one, maybe two, studies, which other scientists told us were flawed.

"There was simply not evidence to justify quite a Draconian step."

Public outcry

The government proposals sparked a public outcry when they were announced last year.

A group of 218 scientists and doctors sent a letter to all MPs claiming that B6 was safe at daily doses of up to 200mg, and that no significant health problems had emerged despite several decades of widespread use.

More than 100,000 letters have also been sent to MPs by consumers complaining about the government decision, and a lobby group called Consumers for Health Choice has spearheaded a campaign of opposition.

At present three million Britons take daily doses of Vitamin B6 up to 200mg. Two million women use the vitamin in high doses to combat pre-menstrual tension, alleviate morning sickness and the side effects of the pill.

More than one million men take it to fight stress and increase energy. B6 is also used in conjunction with magnesium to treat autism.

Loss of sensation

Agriculture minister Jeff Rooker wants tough limits

However, scientists have found that long term use of high doses may affect the sensory nervous system leading to loss of sensation in the hands and feet and permanent nerve damage.

One study suggested that long term use of doses of 500 times the recommended daily level may cause damage to the nervous system.

A second study found adverse effects in humans from ingesting a dose as low as 50mg a day. However the methods used in this investigation have been seriously questioned and the Agriculture Committee concluded it was 'scientifically unjustifiable' to use the research as the basis for setting daily limits on B6 intake.

The committee's recommendations are based on written and oral evidence from a large number of individuals and organisations. The 100mg recommendation is based on findings of the National Academy of Sciences in the US.

Placebo effect

In its conclusions, the committee says: "The fact of the toxicity of vitamin B6 in excess is probably not appreciated by many consumers but then nor are the effects of the consumption to excess of other foodstuffs.

"The government, after all, does not seek to regulate or limit consumption of toxic substances occurring in food and drink, such as caffeine, alcohol or salt.

"People are perfectly entitled to make such choices for themselves, so long as they are provided with sufficient information to avoid the potential health risks of high levels of intake, and so long as dietary supplements do not make medicinal claims."