High doses of vitamins are dangerous, UK report

Related tags Food standards agency Vitamin Fsa

Doses above 1000mg of vitamin C and more than 1500mg daily of
calcium could cause serious health effects, says a new report
commissioned by the UK's Food Standards Agency. The FSA advice,
which also proposes a ban on weight loss supplement chromium
picolinate, is set to shake consumer faith in supplements.

The UK is set to radically lower the levels of vitamins currently available in supplements and will probably ban the mineral chromium picolinate from shelves, following advice from experts who cite health risks from vitamin overdoses and even cancer.

The report, commissioned by the UK's Food Standards Agency (FSA), is set to shake up the natural health industry, with changes to dosages of some of the most commonly used vitamins and minerals, including vitamin C and iron.

The FSA​ warns that levels of vitamin C above 1000mg/day could cause abdominal pain and diarrhoea. In some supplements, vitamin C is available at up to three times this amount. Doses of calcium above 1500mg/day and iron above 17mg/day may also result in similar symptoms in some people, said the report. However the symptoms are not permanent and should disappear once people stop taking the supplements.

The report also finds that chromium in the form of chromium picolinate may have the potential to cause cancer. The Expert group highlighted a study showing that chromium picolinate - a synthetic chromium compound - has caused DNA damage in mammalian cells, and others associating it with renal failure.Consumers are therefore being advised not to take chromium in this form and the FSA is consulting on a proposal to ban its use in the manufacture of food supplements from July next year. Despite this, the Agency confirms that 10mg daily or less in total of chromium in other forms is unlikely to cause any harm.

Other substances under review include beta-carotene, which is thought to increase the risk of lung cancer in smokers and those exposed to asbestos when taken at high doses. Nicotinic acid, zinc, manganese (especially for older people) and phosphorus, are also thought to produce irreversible harmful effects if taken for long periods at the highest supplemental doses, said the FSA.

Current advice on vitamin B6 is also being re-emphasised. The Agency warns against taking more than 10mg/day of vitamin B6 from dietary supplements unless acting on medical advice. It warns that high intakes taken over a long period of time can lead to a loss of feeling in the arms and legs.

Further advice is given on biotin, folic acid, pantothenic acid, riboflavin, niacin, thiamin, vitamin B12, vitamin D, vitamin E, vitamin K, boron, cobalt, copper, iodine, molybdenum, nickel, selenium, tin, magnesium, potassium, and silicon.

Commenting on the safety advice, Sir John Krebs, chair of the Food Standards Agency, said: "We are using an extremely thorough independent expert review of the scientific evidence on the safety of vitamins and minerals as the basis for new advice to help consumers make informed choices. In addition, the Board of the Food Standards Agency will be considering what further action we would wish the supplements industry to take."

The report has prompted widespread industry and consumer reaction. Children's charity The Birth Defects Foundation (BDF) warns that pregnant women could put the health of their unbornchildren at risk following the FSA advice on folic acid - in older people it can conceal the symptoms of B12 deficiency, according to the report. The charity said it has received a flood of callsto its nurse-run helpline, with future mothers questioning the safety of taking folic acid supplements during pregnancy.

Sheila Brown, chief executive of BDF​, which funds research into the cause and prevention ofdefects in the unborn child, said: "There is a great deal of research currently being carried outinto the effects of vitamin supplements on both adults and childrenbut folic acid is medically proven to be save and even essential tothe health of the unborn child. I am concerned that some mum's-to-be could bedeterred from taking folic acid as a direct consequence of the FSA'sreport."

A report in The Times​ yesterday said that Ralph Pike, of the National Association of Health Stores, which represents 12,500 health shops in the UK, was incensed by the 'meddling' of the FSA.

"Where are the dead bodies? There has not been one death anywhere in the world from people taking a legitimate vitamin supplement. The authorities just don't like people taking control of their own health and they want everyone to abrogate responsibility for their lives to the nanny state,"​ he is quoted as saying.

The global natural health industry has suffered a number of attacks recently. In the US, a report in the New York Times​ last week calling vitamins useless will have a considerable effect on consumer purchasing, while in Australia, the country's leading supplement maker has been involved in a major product recall. The industry is under increasing pressure to promote the safety and efficacy of its goods.

The FSA Board is currently working on recommendations to the supplement industry for dose reductions and/or label warnings for some high dose food supplements.

The report was carried out by the Expert Group on Vitamins and Minerals (EVM), which makes recommendations on 31 vitamins and minerals. A draft of the report was issued in September last year.

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