The British media has been enjoying a feeding frenzy over a report that suggests 'minerals and vitamins can cause cancer and liver damage' (The Times), that people are 'poisoning themselves' (Sunday Times), and that their health could be 'irreversibly damaged' (Daily Telegraph).
The report and the ensuing press articles come at an ideal time for the pharmaceutical industry - just when the EU is determining safe levels of vitamins to be sold over-the-counter to consumers. Safe upper levels will be incorporated into a directive that will restrict the sale of vitamins and other nutrients throughout the EU in two years' time.
The report, from the UK Food Standards Agency, and the press coverage that followed will between them probably sound the death knell for the nutritional industry in Britain and beyond. Success in restricting vitamin sales in Europe will be followed by a fresh attempt from the pharmaceutical lobby to reintroduce tighter controls in the USA.
The frenzy has been such that high-dose vitamins have already been found guilty, and, without further delay, the body of nutritional medicine was hanged at 6am GMT yesterday (8 May).
You might be wondering whether you are indeed putting your life at considerable risk by taking vitamins beyond the Recommended Daily Allowance (RDA), and whether you are about to succumb to cancer and liver damage.
It's always worth going back to primary sources to give an intelligent answer. The FSA report was based on a detailed, 350-page study from the Expert Group on Vitamins and Minerals (EGVM). Leaving aside the hysterical, but anticipated, misreadings of British journalists (sadly, their role is vital in this appalling crime against health maintenance), let's restrict ourselves to the reports of the FSA and the EGVM.
There's no doubt that journalists have taken their lead from the FSA, who have taken an extremely 'tabloid' slant on the EGVM study.
In the first place, the claim that 'vitamins and minerals can cause cancer' is a statement restricted to the over-use of chromium, in the form of chromium picolinate, which is available in stores at levels up to 0.6mg. The FSA states that it 'may have the potential to cause cancer'. The EGVM is aware of two cases where the patient died from severe kidney and liver damage after ingesting 7.5 mg regularly, although no cases of cancer came to light. No reactions were reported in people who took up to 1 mg a day for 64 weeks, according to one study.
The FSA reports that doses above 1000 mg a day can cause abdominal pain and diarrhoea. The EGVM says this is a common side effect, but one that disappears immediately once the dosage is stopped or lowered. However, it points to two major trials where people who took 1000 mg a day for five years reported no adverse reactions whatsoever.
The FSA states that doses above 1500 mg a day can also cause abdominal pain. The EGVM says this is most likely to occur if it is taken with antacid tablets, calcium supplements and milk. However, no adverse reactions were reported in trials with people supplementing at doses up to 2000 mg a day.
Abdominal problems occur with iron supplements at a potency above 17 mg a day, says the FSA. Agreed, says the EGVM, but these reactions are more common at daily doses of 60 mg. Studies push the limits higher, and suggest that gastro-intestinal problems occur at doses of up to 200 mg a day.
Beta-carotene: The FSA states that beta-carotene can cause 'irreversible harmful effects'. The EGVM said that studies have shown no toxicity in humans, even among pregnant women. However, trials involving smokers and workers exposed to asbestos found that they were more likely to develop lung cancer if they were also taking beta-carotene. So nothing to do with cigarettes and asbestos, then.
The FSA puts the same claim of irreversible harmful effects at the door of zinc. Again, a careful study of the EGVM report fails to find supporting evidence. It states that zinc can cause reversible abdominal pain, nausea and vomiting, and very high doses might cause blood disorders in diabetics, a very small study suggested.
Again, consumers who supplement with manganese can also suffer irreversible harmful effects, says the FSA. Miners who have inhaled manganese while working in manganese mines and smelters have contracted Parkinson's disease, but these are at levels impossible to ingest, says the EGVM. Trials with supplementation at doses up to 15 mg a day failed to find any adverse effects among the volunteers.
High doses can lead to a loss of feeling in the arms and legs, says the FSA. Agreed, says the EGVM, but this occurs when levels of 2000 mg are taken every day for very long periods. However, this has never been supported by any trials.