Government row flares up over vitamin B-6

BMJ 1998;317:12 ( 4 July )

News

Government row flares up over vitamin B-6

John Warden, parliamentary correspondent, BMJ

Restrictions on vitamin B-6 proposed by the British government on the advice of its own experts have been repudiated by a Commons select committee on the grounds that the advice was scientifically unjustified and palpably wrong

The government is now in the position of either having to rescind the proposed controls or reject the select committee's views and incur the public antagonism it has exposed. Some three million people in Britain take vitamin B-6 as a dietary supplement for relieving stress or premenstrual syndrome.

Many thousands of protest letters to ministers and MPs followed the appearance three months ago of draft regulations effectively banning the general sale of all dietary supplements containing more than 10 mg of vitamin B-6 per daily dose. The consultation period ended on 26 June. Early indications are that ministers are likely to withdraw the proposed regulations.

The agriculture select committee, which monitors food safety, recommends that the government should withdraw the draft regulations and introduce, with the agreement of the health food industry, a voluntary limit of 100 mg per daily dose, pending a report from the committee's expert group on vitamins.

The proposed limit of 10 mg was recommended by the Department of Health's committee on toxicity of chemicals in food, chaired by Professor Hubert Woods of the department of medicine at Sheffield University, after reviewing the evidence of vitamin B-6 overdose neuropathy, and relying heavily on a 1987 study in Acta Neurologica Scandinavica by a London gynaecologist, Dr Katharine Dalton, which put the lowest adverse effect level at 50 mg per day.

In an update for the committee Dr Dalton says that a follow up suggests that women with symptoms of vitamin B overdose in 1987 continued to be at risk of recurrences and their general health was impaired 10 years later.

The select committee, however, took its cue from the US Institute of Medicine, which concluded that 500 mg per day was the lowest observed adverse effect level, and dismissed the Dalton study as flawed. The committee heard evidence that millions of people in Britain take doses above 50 mg per day, and commented: "In the 11 years since the Dalton study... not a single case of peripheral sensory neuropathy shown to be related to [vitamin B-6] has come to light. The probability that this could have occurred had Dalton been correct is, in our view, infinitesimal."

The select committee's report recommends that all dietary supplements containing vitamin B-6 should display a warning that intakes above 100 mg per daily dose may carry health risks.

Vitamin B6 is available from the Stationery Office, price £20.50.
Add to CiteULike CiteULike Add to Complore Complore Add to Connotea Connotea Add to Del.icio.us Del.icio.us Add to Digg Digg Add to Reddit Reddit Add to Technorati Technorati What's this?