Naked Science Forum
Life Sciences => Physiology & Medicine => Topic started by: Prof JAG Wilson on 17/08/2009 12:30:04
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Prof JAG Wilson asked the Naked Scientists:
Hi Chris,
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I listened to part of the show you did on 702 in South Africa on Friday and caught one of the questions on Vitamin C and cancer. I loved your reply but would like to go further, if you get a chance later. Â I am a clinical oncologist so feel strongly about all these stories out there.
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The vitamin C story started with Linus Pauling who did win a Nobel prize but many years ago and NOT for clinical work - he teamed with a Scottish surgeon who had the idea of  high doses of vitamin C and cancer but extremely flawed trial design: patient selection was those deemed by their doctor to be incurable (or words to that effect). The surgeon gave vit C and the survivals were compared to those from patients of other doctors who were not treated.  On review it seems the surgeon was a terrible pessimist and gave up much earlier and so his patients had a significant lead time.
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However, because of the Nobel Prize lots of time and effort and patients were subsequently employed to try to prove this theory at least 3 formal randomised studies from the Mayo Clinic alone none were able to replicate the results and, as you stated, in fact it seemed that toxicity was not insignificant and benefit non-existent. Â But the myths persist.
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I'm sure you know Quackwatch, a great site for checking out myths (although obviously coming from a specific viewpoint).
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Hope you get a chance to straighten out at least one story and maybe save some souls some health and money ( and, yes there are practitioners here offering high dose IV Vit C at around 600 pounds a throw, cash up front – no formal professional registrations).
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Regards
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Jenny Wilson
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Prof Clinical Oncology, University of Pretoria
What do you think?
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You said it. It's a myth.
As you are sure to know, those who succumb to cancer very much want to believe there is something that will cure them. Sadly, this makes them easy targets for unscrupulous individuals who would promote their personal ambitions at the expense of highly vulnerable victims.
As they say: If it looks like a duck, and it quacks like a duck, it's probably a quack.
(I had cancer 24 years ago. Still going strong, thanks to oncologists!)
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Oddly, I received an email today, which I have posted in the relevant 'Email Hoaxes' section of the forum here http://www.thenakedscientists.com/forum/index.php?topic=5237.msg282744#msg282744 (http://www.thenakedscientists.com/forum/index.php?topic=5237.msg282744#msg282744).
Unfounded claims for cancer cures, or any such condition, are pure evil. To prey on people while at their most vulnerable, as I said in the post linked above, is contemptable. For a doctor or scientist to make such claims based on what can only be described as 'bad science' is probably even more contemptable than the one offered by this email.
While many would be sceptical about faith healing, they might not be so sceptical about a cure promoted by someone with a Nobel prize, regardless of what that prize was for, as you quite rightly say, Prof Wilson.
What is even more worrying, is that overdosing on vitamin C might have its own problems. I gather this is still being investigated, but it is suggested that overdosing could interfere with metabolic rate.
It has been reported that Linus Pauling took 12,000mg per day, and raised that to 40,000mg if he had a cold. Who knows if there is any truth in this. But I would suggest he could be a good guinea pig in the vitamin C overdose research.
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"Hope you get a chance to straighten out at least one story and maybe save some souls some health and money ( and, yes there are practitioners here offering high dose IV Vit C at around 600 pounds a throw, cash up front – no formal professional registrations)."
Hell's teeth I can get vitamin C on ebay at about £20 a pound. I would struggle to lift £600 worth. How much does an IV set cost?
Sadly, as with many nice simple ideas, it doesn't work. Vitamin C doesn't cure cancer.
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I heard on the telly this morning that there was a study done in Norway that found that megadoses of vitamins can lead to cancers, including lung cancer.
Here's a link to the segment. Unfortunately, you will have to sit through a commercial before you get to the interview.
http://abcnews.go.com/Video/playerIndex?id=9113414
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i think part of pauling's reasoning was that the intercellular area toughened so that the cancer couldnt spread as fast.
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i can't seem to imagine how Vitamin C could prevent cancer - let alone cure it - when even macrophages would mediate cancer invasion and metastasis.
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I'm sure I read that the body will not absorb? any more vitamin C after its taken in its RDA. Any excess is not stored by the body and discharged of in the urine. Some other vitamins do get stored though and can cause problems with large doses.
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Ascorbic acid induces apoptosis in acute myeloid leukemia cells via hydrogen peroxide-mediated mechanisms
The International Journal of Biochemistry & Cell Biology
Volume 36, Issue 11, November 2004, Pages 2180-2195
http://bloodjournal.hematologylibrary.org/cgi/content/abstract/98/3/805
Blood, 1 August 2001, Vol. 98, No. 3, pp. 805-813
NEOPLASIA
Ascorbic acid enhances arsenic trioxide-induced cytotoxicity in multiple myeloma cells
Jennifer M. Grad, Nizar J. Bahlis, Isildinha Reis, Marc M. Oshiro, William S. Dalton, and Lawrence H. Boise
Phase I clinical trial of i.v. ascorbic acid in advanced malignancy
L. J. Hoffer1,*, M. Levine2, S. Assouline1, D. Melnychuk1, S. J. Padayatty2, K. Rosadiuk1, C. Rousseau1, L. Robitaille1 and W. H. Miller, Jr1
Results: Adverse events and toxicity were minimal at all dose levels. No patient had an objective anticancer response.
Conclusions: High-dose i.v. ascorbic acid was well tolerated but failed to demonstrate anticancer activity when administered to patients with previously treated advanced malignancies. The promise of this approach may lie in combination with cytotoxic or other redox-active molecules.
antioxidants, vitamin C
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Oddly, I received an email today, which I have posted in the relevant 'Email Hoaxes' section of the forum here http://www.thenakedscientists.com/forum/index.php?topic=5237.msg282744#msg282744 (http://www.thenakedscientists.com/forum/index.php?topic=5237.msg282744#msg282744).how old when pauling died? & what did he die of?
Unfounded claims for cancer cures, or any such condition, are pure evil. To prey on people while at their most vulnerable, as I said in the post linked above, is contemptable. For a doctor or scientist to make such claims based on what can only be described as 'bad science' is probably even more contemptable than the one offered by this email.
While many would be sceptical about faith healing, they might not be so sceptical about a cure promoted by someone with a Nobel prize, regardless of what that prize was for, as you quite rightly say, Prof Wilson.
What is even more worrying, is that overdosing on vitamin C might have its own problems. I gather this is still being investigated, but it is suggested that overdosing could interfere with metabolic rate.
It has been reported that Linus Pauling took 12,000mg per day, and raised that to 40,000mg if he had a cold. Who knows if there is any truth in this. But I would suggest he could be a good guinea pig in the vitamin C overdose research.
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If you want to know how vitamin C has the potential to kill cancer cells, I can tell you.
Going so far as calling it a myth is a little rough.
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Nice to see VitaminC around here again! [;)]
Please tell us the truth in this 'ascorbate' (Ascorbic Acid Debate)
iko
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nt J Vitam Nutr Res Suppl. 1982;23:257-63.
The influence of ascorbic acid on the growth of solid tumors in mice and on tumor control by X-irradiation.
Tewfik FA, Tewfik HH, Riley EF.
Abstract
Swiss mice drank either distilled water or 0.1% ascorbic acid in distilled water for one week prior to and during the experiments. Solid tumors were induced by injecting Ehrlich ascites tumor cells i.m. into the hind limb of Swiss male and female mice. It was found that the tumor growth was significantly faster in the mice that were drinking distilled water. Beginning two days after tumor cell injection, the tumor bearing limbs were irradiated every 24 h as follows: a) 6 exposures of 400 R, 500 R, 600 R, or 700 R each, b) 10 exposures of 400 R each, and c) 11 exposures of 400 R each. Our results indicated that when 6 exposures of 700 R each were given every 24 h to mice drinking distilled water, about 80-85% tumor control was achieved; the percent tumor cure was even better in mice drinking ascorbic acid in water than in mice drinking water.
PMID: 6811485 [PubMed - indexed for MEDLINE]
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http://www.indianjcancer.com/article.asp?issn=0019-509X;year=2004;volume=41;issue=2;spage=72;epage=80;aulast=Surjyo
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Oral supplementation of ascorbic acid does little to cancer cells. However, intravenous administration of ascorbic acid has been shown to produce hydrogen peroxide, which is particularly toxic to cancer cells. When Pauling and Cameron did their first work in cancer patients, they used a combination of delivery systems to treat cancer patients - this combination hasn't really been tried until recently.
In essence, you can ignore all the research on cancer treatment and vitamin C from about 2005 onward.
Mark Levine's group at the NIH in Bethesda is doing some wonderful work in this field. Phase I clinical trials haven't been encouraging, but evidence is still increasing that vitamin C does have an effect on cancer cells in animal models. The next questions, in regard to human cancer, are "why is it working?" and "can we make it work better?" Without understanding the mechanism(s) involved, we're still in the dark.
Furthermore, vitamin C has been shown to prevent cancers of the respiratory and digestive tract, but that works by a completely different mechanism. In that case, vitamin C is probably working on carcinogens, detoxifying them before they can do harm. In these instances, it would be a preventative measure.