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Posted August 22, 2011: by Bill Sardi
To the editor
Editor: Paul Dacre
I am writing to complain about an apparent false story released in your publication 3 days ago, according to Google’s log. The report refers to a study that is a decade old. It was reported in Science Magazine in June 15, 2001 and fully rebutted in that same publication on September 14 of that same year. The report, entitled “Vitamin C Cancer Fear” is a total falsehood as it has recently been confirmed that mega-dose vitamin C, given intravenously, is totally non-toxic, transiently creates hydrogen peroxide (H2O2) that selectively kills cancer cells and does not harm healthy cells, and then converts to harmless non-toxic H2O (water). The University of Pennsylvania study was conducted in a lab dish while doses of vitamin C up to 10,000 milligrams had already been tested in humans and found to be non-toxic to DNA. Why has the DAILY MAIL chosen to re-publish a story that is not news and that has been thoroughly dismissed as junk science a decade ago? (See referenced story, referenced reports below)
by JAMES CHAPMAN, Daily Mail
High doses of vitamin C could increase the risk of cancer, scientists warn today.
Their findings suggest that the popular ‘mega-dose’ vitamin C pills may damage cells in the body.
Experts said the study raised real concern about the pills, taken by thousands in the belief that they help ward off colds, protect against heart disease and boost all-round health.
Catherine Collins, chief dietician at St George’s Hospital, London, said people who took the pills were acting as ‘guinea pigs’.
She said: ‘This suggests that there’s a potential risk of having more of a nutrient than the body really needs. There’s all the vitamin C you need in a single grapefruit, but they are taking ten times the amount and who knows what’s going to happen?’
But producers of diet supplements said laboratory experiments did not necessarily reflect what happens in the body.
Britons spend £55million a year on vitamin C pills.The recommended daily intake is between 40 and 60mg, but mega-dose pills can contain up to 1,000mg.
The new study, reported today in the journal Science, could explain why most previous research has failed to confirm the theory that vitamin C supplements offer protection against cancer.
Test-tube experiments at the University of Pennsylvania in Philadelphia suggested that vitamin C can actually trigger a biological process which damages the DNA – or genetic code – in cells. This could create a potential risk of cancer and other diseases such as rheumatoid arthritis.
Dr Ian Blair, who led the research, said: ‘It’s possible vitamin C isn’t working in cancer prevention studies because it’s causing as much damage as it’s preventing, but that’s speculation at this point. What we can say is that vitamin C doesn’t work when you expect it to.’
He stressed that his study did not prove high levels of vitamin C could trigger cancer. Dr Blair said: ‘Just because you damage DNA doesn’t mean you’ll get cancer. But if you really wanted to be cautious, you wouldn’t use supplements.’
The findings were hotly disputed by the Proprietary Association of Great Britain, which represents manufacturers of medicines and supple-ments. A spokesman said: ‘The study must be taken in perspective and should not cause concern.
‘It was performed in test tubes and not in the body.’
He said a similar study in Finland had not identified any problem. The spokesman added: ‘Vitamin C is an essential antioxidant, which protects the body against potentially-damaging free radicals. It helps fight infection and is essential for wound healing.
‘It’s also needed for the formation of collagen, for healthy skin and for the formation of other structural materials in bones, teeth and capillaries.’
But Dr Arthur Grollman of the State University of New York, an expert on the causes of cancer, said the implication of the research was serious.
He said: ‘Far more caution should be taken over dietary supplements – there should be an insistence on real proof that there’s a benefit before taking any.’
Diet experts strongly advised people to stay close to the recommended daily allowance of vitamin C. In the UK, the Government’s Committee on Medical Aspects of Nutrition suggests 40mg a day, while the European Commission level is 60mg.
Dr Wendy Doyle, of the British Dietetic Association, said the findings reinforced the message that vitamins should be obtained from natural sources.
She said: ‘Fruit and vegetables also contain other plant chemicals that are health-promoting.’
Science. 2001 Jun 15;292(5524):2083-6.
Lee SH, Oe T, Blair IA.
Center for Cancer Pharmacology, University of Pennsylvania, 1254 BRB II/III, 421 Curie Boulevard, Philadelphia, PA 19104-6160, USA.
Epidemiological data suggest that dietary antioxidants play a protective role against cancer. This has led to the proposal that dietary supplementation with antioxidants such as vitamin C (vit C) may be useful in disease prevention. However, vit C has proved to be ineffective in cancer chemoprevention studies. In addition, concerns have been raised over potentially deleterious transition metal ion-mediated pro-oxidant effects. We have now determined that vit C induces lipid hydroperoxide decomposition to the DNA-reactive bifunctional electrophiles 4-oxo-2-nonenal, 4,5-epoxy-2(E)-decenal, and 4-hydroxy-2-nonenal. The compound 4,5-Epoxy-2(E)-decenal is a precursor of etheno-2′-deoxyadenosine, a highly mutagenic lesion found in human DNA. Vitamin C-mediated formation of genotoxins from lipid hydroperoxides in the absence of transition metal ions could help explain its lack of efficacy as a cancer chemoprevention agent. PMID:11408659
Science 14 September 2001:
Vol. 293 no. 5537 pp. 1993-1995
S. H. Lee and co-authors suggest on the basis of their research findings that high doses of vitamin C could potentially promote DNA damage that could lead to cancer (Reports, “Vitamin C-induced decomposition of lipid hydroperoxides to endogenous genotoxins,” 15 Jun., p. 2083). Their report could leave the impression that no human studies have been performed to address this question.
In fact, five human studies have been conducted that do not confirm Lee et al.‘s speculation (1–5). For example, researchers at Johns Hopkins University could not find evidence of a “significant main effect or interaction effect on oxidative DNA damage in non-smoking adults” with 500 mg per day of vitamin C supplementation (1). In a German study, researchers found that 1000 mg of vitamin C consumed by smokers and nonsmokers for 7 days did not produce DNA damage, as measured by the number of micronuclei in blood lymphocytes (2). And in yet another study conducted by Immunosciences Laboratory in California, 20 healthy volunteers were divided into four groups and given either placebo or daily doses of 500, 1000, or 5000 mg of vitamin C (ascorbic acid) for 2 weeks. The researchers concluded that “ascorbic acid is an antioxidant and that doses up to 5000 mg neither induce mutagenic lesions nor have negative effects on natural killer cell activity, apoptosis, or cell cycle” (3).
Free Rad. Res.34, 209 (2001).
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