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STUDY REPORT CREATES VITAMIN C SCARE

According to Ralph Moss, "What I find particularly astonishing is that later in 1998, the authors of the original study published another report on vitamin C. This showed that people who received 500 mg of vitamin C per day had substantial benefit from the practice! These results illustrate... a role for vitamin C in the regulation of DNA repair enzymes and demonstrate an "antioxidan't effect" they wrote.[Cooke, MS, et al Novel repair action of vitamin C upon vivo oxidative DNA damage FEBS Lett 1998 Nov 20,439(3):363-7.]

Why didn't this follow-up, positive report make world-wide headlines? The health of millions could be adversely affected.


The Vitamin C Foundation Technical Advisors respond to the April 8, 1998 news that vitamin C "in excess of 60 mg might increase oxidation damage in the body causing arthritis and cancer".

BOTTOM LINE:
There isn't a single shred of hard evidence to back up the speculative health claims published by Jane Brody in the New York Times, i.e. that doses of Vitamin C above the RDA may be harmful in any way, shape or form. No DNA damage was demonstrated by the English experiment. The measurement that showed potential damage was an old way to measure DNA damage. The reason for the experiment was to evaluate a newer technique, less prone to error. Only the old technique indicated possible damage. The newer technique did not. This fact went unreported by Nature.

Consider this: If vitamin C did cause DNA damage, most of the wild kingdom would not be able to reproduce without mutation. Almost all animals make vitamin C in high amounts.

So what is going on here? It does not follow by logic that Vitamin C is harmful, nor would the consequences postulated by Jane Brody necessarily follow.


These fears are pure speculation...


Balz Frei, a professor and director of the Linus Pauling Institute at OSU, says
"The new finding is contrary to many others, directly contradicts at least one other recent study, and focuses too narrowly on a single biological "marker" that has yet to be proven as a good indicator of oxidative stress and cellular damage."

Entire Response of Dr. Balz Frei at the Linus Pauling Institute, Oregon State University.


Jack Challem, publisher of the independent NUTRITION REPORTER says
"This study, which has alarmed so many people, was described in a short letter to Nature. The researchers measured only two of the 20 markers of free radical damage to DNA. We have no idea how vitamin C affected the other 18 markers of DNA damage.

We also don't know if the DNA breaks occurred on single strands or double strands of DNA. This is not an arcane point. Single-strand DNA breaks occur all the time, and most are quickly fixed by B-vitamin-dependent DNA repair enzymes. Double-strand DNA breaks would be much more serious because they are more difficult to repair.

Bruce N. Ames, Ph.D., of the University of California, Berkeley, has often pointed out that about half of all chemicals, natural and synthetic, cause DNA damage. He notes that naturally occurring compounds in alfalfa sprouts (canavanine), broccoli (isothiocyanate), potato (solanine), celery (psoralen), and onion (quercetin), and most fruits and vegetables cause DNA damage"


Entire Challem Response

Dr. Robert Cathcart, MD, has treated over 20,000 patients worldwide with dosages of ascorbate many orders of magnitude higher than the U.S. RDA. We have asked Dr. Cathcart to comment on the incidence of Cancer and Arthritis among his patients. (Dr. Cathcart has previously commented that heart disease is "unknown" in his practice.)

Dr. Cathcart's preliminary response:

Clinically, I have seen no evidence of DNA damage. I have seen a few cancer patients who have taken vitamin C fairly regularly for a number of years but there are not many and in the large number of patients I have put on large doses of C there seems to be a smaller than normal number who have developed cancer.

I know that follow-up in a private practice is not perfect but I have not seen a single autoimmune disease such as rheumatoid arthritis develop while the patient was on large doses of ascorbic acid.

What is very remarkable is that I cannot recall a single patient who had a good heart before starting large doses of ascorbic acid who ever developed a heart attack after being on ascorbic acid. This would seem to be true of all of the arteriosclerotic problems. I actually find this hard to believe but a least in my limited experience, it is true.

On the subject of cancer: there is a remarkable lack of new cancer developing in AIDS patients after they have been on the large doses of ascorbic acid in combination with my whole nutritional program for AIDS. [Robert Cathcart, III, MD, April 10, 1998]


Foundation Asks New York Times Chairman for FACTS to back up Brody Article:

  1. April 11, 1998 Letter
  2. April 13, 1998 Letter
  3. April 17, 1998 Letter
  4. April 18, 1998 Letter

As of this writing, we have traced the basis of the news report to Victor Herbert, Karl E. Herbert and British Researchers Ian Podmore and Joseph Lunec. We have written to Dr. Podmore asking for clarification of the findings reported in NATURE. We'll post any response when it becomes available. Until then it is unknown whether Joseph Lunec or Ian Podmore have drawn these surprising conclusions from their research, or whether others have possibly miss-interpreted the results of this six week study.

The study authors themselves have questioned the reliability of such DNA damage measurements in the past:

  The extraction of DNA prior to use of either of these methods is an area of much controversy as several workers have suggested that cell lysis and/or extraction with organic solvents can cause artefactual generation of 8-OHdG.  One must therefore be careful in interpreting the results of such measurements on the grounds of a suitable method of extraction which does not generate in vitro artefact. [J. Lunec, Q. Zheng, M. Evans, K. Herbert. (Full citation below)]

From the authors paper, we find that when the newer method was used for 8-OHdG, both vitamin E and C showed benefit, as oxidation damage decreased by 50%. (We have not yet be able to determine the method used to determine 8-OHdA, the result that sparked this health scare. Please note, measuring 8-OHdA was not mentioned in the study abstract as either an objective or priority.)

JUNK SCIENCE

For the record, here are some concerns about the NATURE report.
  1. The study was published as a letter to the editor to NATURE. According to this letter, the study was run in 1995, or earlier, so the first question is, why did a study run three years ago suddenly become major news, especially since they couldn't get their findings published in a peer-reviewed journal? And when were these measurements actually made?

  2. The result was a secondary finding. According to the study abstract we found on the internet:

    The aim of this study was to investigate the effect of vitamin C mg/day) and vitamin E (400 i.u./day) supplementation in normal individuals in terms of lymphocyte levels of the base-lesion 7, 8-di hydro 8-oxo-2-deoxyguanosine (8-oxoG)which is recognized as a specific marker of ROS induced damage, in vivo.

    However, their conclusion states:

    Levels of 8-oxodG were unaffected by placebo, but were significantly reduced by approximately 50% by both vitamin C and vitamin E.

  3. The vitamin E measurements were omitted from the NATURE report.

  4. The DNA extraction methods the team employed (that seemed to show damage) are unknown, but since a new method was the purpose of the study (and the new method showed great benefit to vitamin C) we must assume the older method was measured for comparison. Only the comparison measurements showed damage. According to the author's earlier research, the newer methods are needed because the old methods may not be reliable. (As in all science, these results will have to be replicated by other researchers before they can be taken seriously.)

  5. It is uncertain how accurate any of these arcane "damage" measurements are. In other words, there may in-fact be no RNA/DNA damage what-so-ever.

  6. The researchers mention a strong "anti oxidant" affect of Vitamin C at the same time coupled with a profound "pro oxidant" affect. (Vitamin C is already known to have both these properties. Since this property was unknown to the authors, this property may have affected the experiment.)

  7. It does not make sense that a "6 week" study of low dose ascorbate in humans (several weeks on placebo) could isolate DNA/RNA damage to the vitamin C supplement. (Especially if turns out that the same "damage" could be caused by an extra onion or two on a hamburger...)

  8. Any theory of "Vitamin C causes DNA damage" must explain that lack of any clinical or epidemiological evidence in the great many people taking far greater amounts of vitamin C than the RDA. In fact, these study results, if born out, may call into question the value of these so-called "8-oxodA markers" that are "recognized as specific for free radical induced damage."

  9. One would hope that preliminary work in guinea pigs, one of the few species that does not make its own vitamin C, had been done before a story like this gets publicity. (Brody mentioned mice. Mice make their own vitamin C so any research with mice is useless.)

  10. There is nothing in the study that indicates 500 mg has any special significance -- other than that is the amount they chose to investigate. Yet, the Brody article makes 500 mg into a significant "finding."

  11. If a theory is postulated that vitamin C in large amounts causes "arthritis and cancer" then it would have to explain why this process does not appear to be present in animals.

    Most animals must obtain the various vitamins and minerals in their diet to survive. Vitamin C is an exception. Unlike humans, most animals make their own vitamin C in their bodies in very large amounts. This vitamin C, adjusted for body weight, averages 9,000 to 12,000 mg and goes directly into the blood stream. (We humans would have to ingest some 18,000 to 24,000 mg by mouth to get this much in our blood stream and tissues.)

So why did this study get so much press? (That's what we'd like to know.)

BOTTOM LINE: There isn't a single shred of hard evidence to back up the speculative health claims published by Jane Brody in the New York Times, i.e. that doses of Vitamin C above the RDA may be harmful in any way, shape or form. We doubt these results will be repeated, but even if they are and the known "pro-oxidant" property of Vitamin C is being measured by this experiment, it does not follow by logic that Vitamin C is harmful, nor would the serious postulated consequences necessarily follow. These fears are pure speculation. (There is no epidemiological or other evidence that high vitamin C plays a role in the formation of chronic disease. If fact, as we will begin to publish in MEGASCORBATE THERAPIES, a massive body of evidence exists that supports the opposite conclusion. That so-called high amounts of supplement ascorbate (Vitamin C) are in fact PROTECTIVE of these diseases.)


Rhetorical Question: If vitamin D helps prevent breast cancer, and if cholesterol is required with sunlight to make vitamin D in our bodies (it is), then do cholesterol lowering drugs contribute to breast cancer? This is the same logic, by the way, that medicine uses to connect vitamin C to kidney stones, and now to arthritis and cancer. No experimental proof. Why is this logic appropriate in one argument, but not another?


The fact that vitamin C has pro-oxidant as well as anti-oxidant properties is well known and not news. In 1986 Linus Pauling wrote in his book HOW TO LIVE LONGER AND FEEL BETTER in the chapter Vitamins in the Body:

"The ways in which ascorbic acid (Vitamin C) functions in the human body relate first to the fact that it engages on both sides of the universal oxidation-reduction reaction that subtracts or adds hydrogen atoms to a molecule. (Vitamin C) is readily oxidized to dehydroascorbic acid by the surrender, to oxidizing agents, of the two hydrogen atoms... [shown in the figure]

This action is readily reversible, for dehydroascorbic acid acts as a strong oxidizing agent, and by picking up two hydrogen atoms is reduced to ascorbic acid. It is likely that the reducing power of ascorbic acid and the oxidizing power of dehydroascorbic acid are responsible for some of the physiological properties of the substance." [PAULING, 1986]

It is strange how a conclusion of potential harm can be drawn from the Lunec, et. al. study without hard evidence of cause and effect, to say the least. Especially on the wings of the announcement that for the first time ever, the National Academy of Sciences is recommending that Americans take vitamin supplements.

Speaking of wings, while airplanes have them, it does not mean that if it has wings, it is necessarily an airplane. Even if the oxidation "damage" that researcher Lunec studied are always present in cancer and arthritis patients, it does not follow that these markers are the cause of these diseases, nor can vitamin C be blamed if it too seems to create these oxidation markers in laboratory experiments.

Our official response will be published here. While we wait to sort this story out, people worried about this report ought to keep our animal friends in mind. Like humans, most animals must obtain the various vitamins and minerals in their diet to survive.

Vitamin C is an exception.

Unlike humans, most animals make their own vitamin C in their bodies in very large amounts. This vitamin C, adjusted for body weight, averages 9,000 to 12,000 mg and goes directly into the blood stream. (We humans would have to ingest some 18,000 to 24,000 mg by mouth to get this much in our blood stream and tissues.)

If a theory is postulated that vitamin C in large amounts causes "arthritis and cancer" then it would have to explain why this process does not appear to be present in animals.

Jane Brody of the New York times even quoted Lunec as saying on the basis of their findings it "would be unethical to test higher levels" of vitamin C on people. Coincidentally, the Foundation resubmitted our proposal on April 6, 1998 to the NIH to study high doses of vitamin C on heart disease. Maybe it isn't a coincidence.

Stay tuned. According to Stephen Sheffrey, D. D. S., a strong pro-Vitamin C advocate:

"The ongoing effort to discredit vitamin C began in the 1940s after it was shown to have anti viral and antitoxic properties. Certain members of the pharmaceutical-medical complex, after first promoting vitamin C as a treatment for fevers and infections, realized that widespread use of this non prescription substance would cancel the need for developing a lucrative prescription anti viral drug market.

For this reason, all the scientific trials which have not shown vitamin C to be of any benefit against viral attacks either shorted the recommended dose or altered the recommended treatment procedure. Anyone who knows the vitamin C has been blatantly discredited in this manner should be ashamed to speak of ethics in order to forestall a proper evaluation of the vitamin's therapeutic potential.

I wonder if [Lunec] can point to an increase in heart trouble along with an increase in vitamin C consumption. I believe that just the opposite has occurred."

We consider the following AP article to be much more appropriate than Jane Brody's one sided articles from the New York Times syndicate. Following the AP report are some abstracts of papers written by Joseph Lunec, et. al.


Other News

Study Questions Vitamin C Claims

By MALCOLM RITTER AP Science Writer

NEW YORK (AP) -- Vitamin C's theorized ability to protect against cancer and heart disease appears to diminish at high doses, and the vitamin might even become harmful, a researcher says.

A study indicates that at 500 milligrams a day, ``it's really no particular help at all'' at discouraging oxidation, a damaging chemical reaction linked in theory to those two diseases, said Joseph Lunec of Leicester University in England.

The study found evidence that at 500 milligrams, Vitamin C both suppresses and promotes oxidation, with the effects apparently canceling themselves out, Lunec said.

At even higher doses, Lunec suggested, the harmful effects might prevail. That is, Vitamin C might actually promote oxidation.

Experts were wary of Lunec's brief report, which appears in the April 9 issue of the journal Nature.

The dose tested in the study is a bit more than eight times the standard recommended dietary allowance, but it can be found in some supplements sold at stores.

At 500 milligrams a day, ``although we see a profound protective effect, we also see a definite adverse effect'' that ``would negate any protective effect you have,'' Lunec said Wednesday.

He and colleagues gave 30 healthy volunteers 500 milligrams of vitamin C a day for six weeks. Before and during the vitamin treatment, researchers looked at two indicators of oxidation damage in DNA from the volunteers' white blood cells. While the volunteers were taking supplements, one indicator showed less oxidation and the other indicator showed more, compared to before the supplementation began.

That raises questions about the vitamin's antioxidant abilities at this dose, the researchers said.

But Dr. Steven Zeisel of the University of North Carolina at Chapel Hill said the mixed result is puzzling. The study ``is not a definitive help in our understanding about whether vitamin C is protective or not'' at high doses, he said.

Bruce N. Ames of the University of California at Berkeley, said he suspects the result may have been influenced by the study's lab procedures. Dr. Mark Levine of the National Institutes of Health said the volunteers' white cells may have been saturated with vitamin C before they took supplements. If so, it's hard to see how supplements could make any difference, he said.

Lunec said that researchers are now studying why the mixed result occurred, but that it is not surprising.

AP-NY-04-08-98 1803EDT

Copyright © Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

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04/08

Abstracts

ESCODD: European Standards Committee on Oxidative DNA Damage.
J. Lunec, Q. Zheng, M. Evans, K. Herbert.
Division of Chemical Pathology, University of Leicester, Centre for Mechanisms of Human Toxicity, Hodgkin Building, PO Box 138, Lancaster Road, Leicester LE1 9HN, UK.

8-hydroxyguanine (8-oxoG) can be measured by HPLC and GCMS procedures, while the corresponding nucleoside 8-hydroxydeoxyguanosine (8-OHdG) is most frequently measured by HPLC.  This product has also been measured most frequently in cells as a measure of oxidative damage to DNA in vivo.  Another less common procedure is measurement of the base lesion 8-oxoG by GCMS.  The extraction of DNA prior to use of either of these methods is an area of much controversy as several workers have suggested that cell lysis and/or extraction with organic solvents can cause artefactual generation of 8-OHdG.  One must therefore be careful in interpreting the results of such measurements on the grounds of a suitable method of extraction which does not generate in vitro artefact.  The HPLC procedure usually relies on enzymic digestion of DNA with endonucleases, although ‘hybrid’ HPLC procedures do exist,  it has been suggested that HPLC underestimates in vivo levels of 8-OHdG because the digesting enzymes appear not to be able to digest areas which have 8-OHdG incorporated, compared to areas containing the native nucleoside.  Identification of the 8-OHdG lesion by HPLC has also been questioned on the basis of changing retention times and overlapping, interfering peaks.  GCMS relies on acid hydrolysis with formic acid followed by derivatisation and gas chromatography.  It has been suggested that derivatisation may have contributed to the "high" levels quoted for background DNA damage.  On the other hand it has also been suggested that HPLC may underestimate true DNA damage in vivo while GCMS may overestimate.  It is unclear which analysis is correct, if indeed either is.  Clearly a quality assurance standard needs to be established.  As part of a MAFF supported project we have synthesised a variety of oligonucleotides with 8-OHdG incorporated into a 20 mer structure.  It is then diluted with poly dT to a level which approximates between published values measured by HPLC and GCMS.  Our ultimate aim is to harmonise the analysis of 8-OHdG internationally because of discrepancies reported World Wide in the measurement of this lesion.  In a pilot study four samples were sent to nine different laboratories in the first ESCODD interlaboratory comparisons trial for the measurement of 8-oxoG, 8-OHdG.  The four samples included a sample of pure 8-OHdG which was to be reconstituted by each laboratory; a sample of oligo containing 8-OHdG, also to be reconstituted by each participating laboratory; a sample of lyophilised calf thymus DNA and a sample of pig liver tissue (fresh).  The standard 8-OHdG would test the standard calibration curve of the lab,  the 8-OHdG would test the digestion procedure and accuracy of participating laboratory analysis.  The calf thymus was included to test the comparison and consistency with published values in the literature, and the pig liver was sent to each laboratory to determine the relative efficiency of different extraction procedures for DNA.  In this first round of ESCODD, trial participants were asked to assay samples three times on three separate occasions and asked that injections onto HPLC or GCMS be analysed in triplicate.  This was carried out in order to calculate within and between batch coefficients of variation for each of the four samples.  Several tentative conclusions could be made on the basis of these first pilot results.  Analysis of the four samples confirmed that there is a wide discrepancy between the two major procedures as well as analysis between laboratories underline the need for an international quality assurance standard for this assay.

Vitamin C & Vitamin E supplementation reduces 8-oxodG levels in vivo.
J. Lunec, I. Podmore, H.R. Griffiths, K. Herbert, P. Mistry, N. Mistry
Division of Chemical Pathology, University of Leicester, Centre for Mechanisms of Human Toxicity, Hodgkin Building, PO Box 138, Lancaster Road, Leicester LE1 9HN, UK

  It has been postulated widely that dietary supplementation with antioxidant vitamins may protect humans against cancer by minimising the extent of in vivo oxidative DNA damage.  The aim of this study was to investigate the effect of vitamin C (500 mg/day) and vitamin E (400 i.u./day) supplementation in normal individuals in terms of lymphocyte levels of the base-lesion 7, 8-di hydro 8-oxo-2’deoxyguanosine (8-oxoG) which is recognised as a specific marker of ROS induced damage, in vivo.
  During the study two techniques, high performance liquid chromatography (HPLC) and (GCMS), were established for determining oxidative DNA lesions in peripheral blood lymphocytes.  After isolation of DNA, both methods require an initial formic acid hydrolysis step, to release both native and modified bases from DNA.  For the HPLC assay, a novel procedure was developed utilising the enzyme guanase in an additional hydrolysis step, which selectively deaminates guanine to form xanthine, thereby eliminating the guanine peak, which would otherwise co-elute with 8-oxoG and compromise the assay.  For GCMS, the DNA hydrolysate was separated (as trimethylsilyl derivatives) using GCMS with subsequent identification by quadruple mass spectrometry in selected ion monitoring mode.
  In a placebo-controlled supplementation study 30 normal, healthy individuals received six weeks placebo followed by six weeks of vitamin C (500 i.u./day).  Following a washout period of 5 weeks the trial was repeated using supplementation of vitamin E (400 i.u./day).  Blood was taken at intervals for analysis of vitamin E and C and 8-oxodG by the two methods described above.  8-oxo adenine (8 oxo A) a corresponding oxidative damage product for the base adenine was also measured for comparison.  The sample were taken as follows:-  baseline, week 3 placebo, week 6 (placebo), week 9 (supplementation) and week 12 supplementation.  At week 27 a washout sample was analysed to determine any post supplementation effect.
  Levels of 8-oxodG were unaffected by placebo, but were significantly reduced by approximately 50% by both vitamin C and E.  In the case of vitamin C, this change was found to be significant by both GC-MS and guanase, but by the guanase method only, for supplementation with vitamin E.  8-oxoA was unaffected by placebo C or E.  However, there was a significant increase of 8-oxoA caused by vitamin C supplementation but not by vitamin E.
  This work demonstrates that dietary antioxidant supplementation does affect the degree of oxidative base damage within DNA in vivo.  It also suggests that vitamin C may have a dual effect, in vivo, on oxidative damage since there was a differential effect on 8-oxoG versus 8-oxoA lesions.

Recent method development on the analysis of 8-OH-dG
Lennart  Möller, Tim Hofer, Jean Cadet and Magnus Zeisig
Karolinska Institute, Dep. for Biosciences, CNT, Novum, SE-141 57 Huddinge, Stockholm, Sweden.

  8-OH-dG is a biomarker for oxidative stress on DNA. Elevated levels have been shown after different environmental exposures and in a number of diseases related to oxidative stress. One major problem during work-up and analysis is the risk for dG to be oxidized to 8-OH-dG, with false high levels as a result.
  In the HPLC-EC method we have found that the presence of phenol does not induce 8-OH-dG. Neither is it necessary to work under an inert atmosphere which is very expensive and time consuming.  Important factors for the induction of 8-OH-dG are high temperatures and the use of tap water.  Fe2+ is a potent catalyst in oxidation and ascorbic acid is extremely potent as an oxidizer. An addition of a nitroxide make it possible to work under a normal atmosphere with very low background values and a low standard deviation.
  32P-HPLC Is a very sensitive method to analyze DNA adducts which mainly has been used for analysis of aromatic DNA-adducts. There is a great risk for oxidation of dG when this method is used. The main problem is the presence of the isotope 32P emitting electrons that react with water forming hydroxyl radicals attacking dG. The result are 8-OH-dG levels 10-50 times higher than detected with the HPLC-EC method.
  32P-HPLC is very efficient and sensitive in the analysis of 8-OH-dG but dG must consequently be removed early in the work-up procedure. Doing this, there are no possibilities for oxidation of dG during the other parts of the method. The advantage is that 32P-HPLC only requires small amounts of DNA and has a high sensitivity.

Mutagenesis and carcinogenesis induced by oxidative DNA damage; roles of 8-hydroxyguanine and 2-hydroxyadenine
H.  Kasai, H. Kamiya, T. Hirano, R. Yamaguchi, S. Asami, Y. Tsurudome, M. Inoue.
University of Occupational and Environmental Health, Kitakyushu, Japan

  Oxygen radicals induce various types of oxidative base damage such as 8-hydroxyguanine (8-OH-Gua) and 2-hydroxyadenine (2-OH-Ade) in DNA or its precursors.
  We have developed a new strategy for the evaluation of the mutagenicity of a damaged DNA precursor in E.coli. We introduced 8-OH-dGTP and 2-OH-dATP into E.coli and selected mutants of the chromosomal lacI gene. The 8-OH-dGTP induced AT->CG transversions and 2-OH-dATP elicited GC->TA transversions specifically. This new method enables the evaluation and comparison of the mutagenic potentials of damaged DNA precursors in vivo.
  8-OH-Gua is widely used as a marker of oxidative DNA damage. We found that 8-OH-Gua increased in the lung DNA of rats and hamsters after intratracheal administration of crocidolite asbestos. We detected an increased level of  8-OH-Gua in esophageal DNA after long term administration of ethanol with autoclaved diet. These results were supported by the increase of 8-OH-Gua repair activity. We also found that 8-OH-Gua levels of rat organ DNA increased after forced exercise but decreased after spontaneous exercise. As for human samples, we observed association between the number of cigarette smoked and 8-OH-Gua levels in DNA of leukocytes and the central part of the lung, and found an increased level of 8-OH-Gua in peripheral part of lung from lung cancer patients when compared to non-cancer control.