Posted by Larry Hoover on March 25, 2007, at 10:25:28
In reply to Re: neighbourhood, posted by Klavot on March 25, 2007, at 8:11:36
> In 1994, Robinson and two colleagues summarized the results of four mouse studies he had carried out while working at the Pauling Institute [20]. Nearly all of the mice developed skin cancers (squamous cell carcinomas) following exposure to ultraviolet radiation. Altogether, 1,846 hairless mice received a total of 38 different diets. The researchers found that (a) the rate of onset and severity of tumors could be varied as much as 20-fold by just modifying dietary balance; (b) diets with the worst balance of nutrients had the greatest inhibitory effect on cancer growth; and (c) no cures or remissions were observed (although the researchers were not looking for this). In 1999, Robinson commented:
>
> The results of these experiments caused an argument between Linus and me, which ended our 16-year period of work together. He was not willing to accept the experimentally proved fact that vitamin C in ordinary doses accelerated the growth rate of squamous cell carcinoma in these mice.The fact is, Robinson didn't prove that. He demonstrated that various forms of malnutrition stunted cancer growth. I always find reading the original text to be illuminating. If we go back to the 1994 paper, we'll find this:
http://www.nutritionandcancer.org/view/nutritionandcancer/oism_nac.pdf
Abstract: "...These experiments suggest that dietary variation in general and intentional malnutrition in particular should be given special attention to the control of existing cancer in humans."
Text:
"At certain times, mice with some diets were afflicted with severe and wide-spread lesions, whereas those receiving other diets appeared lesion-free. Eventually, however, nearly all of the mice developed squamous cell carcinoma. For these reasons, it is likely that our results relate primarily to the rate of growth of cancer lesions rather than to the prevention or destruction of cancer.""It is possible, for example, that diets which increase systemic resistance to the production and establishment of cancer cells as growing cancer tissue may be counterproductive for the inhibition of growth of established cancer tissue....the overall results suggest that those diets that would conventionally be considered least suitable for ordinary mouse and human nutrition caused the greatest inhibition of cancer growth."
"Thus a daily intake of ordinary supplements of vitamin C, vitamin E, and multivitamins, a 'well balanced' amount of fruit, vegetables, seeds, and nuts, and minimal amounts of candy and other sweets -- a diet considered healthy for most Americans -- would appear to be harmful for a cancer victim; whereas insufficient protein and fat, high 'empty calories' from sucrose, and near lethal amounts of vitamin C would appear good for a cancer victim."
Cancer grows better when the body is fully nourished. I don't think there's any surprise there. Just how to restrict cancer growth without starving the patient to death is still an ongoing area of research. Methionine restriction seems to be one active field of study.
And I have to take issue with a glaring discrepancy between the experimental results and the conclusions reached. In Experiment 1, this is what was found: "The Black mixture (i.e. normal diet, with added glutatione, BHT, vitamins E and C) clearly suppressed cancer, 12 g/kg vitamin C was indistinguishable from control, 0.535 g/kg vitamin E and sea water were a little higher than control, and the meganutrient mix enhanced cancer growth as compared to control."
Just look at Table 1, for the dramatic effect of the "Black" diet. Yet, the authors go on to say, "Therefore, unless an unusual synergism is present, the suppressive ingredients in the Black mixture were not vitamin C or vitamin E." Not only is there no evidence upon which to support that conclusion (i.e. the experiments with variations on the Black diet were not conducted), we now know that there is a huge synergism between the antioxidants which characterize the Black diet. They simply dismiss their best evidence, due to what can only be called bias.
> At the time, Linus was promoting his claim that "75% of all cancer can be prevented and cured by vitamin C alone." This claim proved to be without experimental foundation and not true. . . .
Again, not so fast, Mr. Robinson. Mr. Pauling had some pretty strong evidence for his over-generalized hypothesis. Just a sample of what Pauling published:
Int J Vitam Nutr Res Suppl. 1982;23:53-82.
Incidence of squamous cell carcinoma in hairless mice irradiated with ultraviolet light in relation to intake of ascorbic acid (vitamin C) and of D, L-alpha-tocopheryl acetate (vitamin E).
Pauling L, Willoughby R, Reynolds R, Blaisdell BE, Lawson S.We have carried out a study of large malignant skin tumours (squamous-cell carcinomas) and other lesions in "hairless" mice (in groups of 45 or 60 mice) intermittently exposed to ultraviolet light over a period of 15 weeks, beginning when the mice were about 8 weeks old. Various groups were given a standard diet (Wayne Lab-Blox) or the same food with added vitamin C or vitamin E throughout the study. Lesions, classified by histopathologic study as atypical squamous-cell proliferations varying from early actinic keratoses to invasive poorly differentiated squamous-cell carcinomas, had begun to develop by the end of the period of irradiation. They were counted twice a month for five months. The observed fraction of mice that developed lesions during successive time periods was analyzed by the statistical method recommended by a committee of the International Agency for Research on Cancer. A pronounced effect of vitamin C in decreasing the incidence of the malignant lesions was observed with very high statistical significance. No significant effect of vitamin E was observed. We conclude that vitamin C should be given special attention with respect to the relation between diet and cancer.
> Vitamin C increased the rate of growth of cancer at human equivalents of 1 to 5 grams per day, but suppressed the cancer growth rate at doses on the order of 100 grams per day (near the lethal dose), as do other measures of malnutrition [21]."Increased compared to what? Again, the increase was in comparison to malnourishment. And, he confounds, once again, cancer induction and cancer growth. Pauling spoke of incidence. Robinson studied growth rate of existing lesions. I grant that Pauling did not cure cancer with vitamin C. But he had solid evidence for reduced induction of cancerous lesions.
> Sometimes I get the impression that alternative practitioners are simply unprepared to accept that their work might be wrong.
>
> KlavotThis work was done in a climate of absolute malevolence. You really ought to read this essay:
http://www.internetwks.com/pauling/hoffer.htmlBruce Ames, the originator of the Ames test for in vitro carcinogenicity/mutagenicity, has continued to explore the effects of nutrient deficiencies on health parameters. Here are some of his recent publications (full-text links):
A general treatise on mitochondrial decay with aging...
http://www.nature.com/embor/journal/v6/n1s/full/7400426.htmlThe effects of gamma-tocopherol on tumour growth....N.b. Most studies have been done on alpha-tocopherol, which actually blocks the effects of gamma-tocopherol, leading to mistaken conclusions about the impact of vitamin E supplementation.....
http://www.pnas.org/cgi/content/full/101/51/17825The DNA-damaging effects of folate deficiency, similar to high-dose gamma radiation....
http://www.fasebj.org/cgi/reprint/03-0382fjev1The modulation of disease-causing genetic polymorphisms via high-dose vitamin therapy....
http://www.ajcn.org/cgi/content/full/75/4/616And I wish I had the full-text for these two:
Ann N Y Acad Sci. 1999;889:87-106.
Micronutrient deficiencies. A major cause of DNA damage.
Ames BN.
University of California, Berkeley 94720-3202, USA. bnames@uclink4.berkeley.eduDeficiencies of the vitamins B12, B6, C, E, folate, or niacin, or of iron or zinc mimic radiation in damaging DNA by causing single- and double-strand breaks, oxidative lesions, or both. The percentage of the population of the United States that has a low intake (< 50% of the RDA) for each of these eight micronutrients ranges from 2% to 20+ percent. A level of folate deficiency causing chromosome breaks occurred in approximately 10% of the population of the United States, and in a much higher percentage of the poor. Folate deficiency causes extensive incorporation of uracil into human DNA (4 million/cell), leading to chromosomal breaks. This mechanism is the likely cause of the increased colon cancer risk associated with low folate intake. Some evidence, and mechanistic considerations, suggest that vitamin B12 and B6 deficiencies also cause high uracil and chromosome breaks. Micronutrient deficiency may explain, in good part, why the quarter of the population that eats the fewest fruits and vegetables (five portions a day is advised) has about double the cancer rate for most types of cancer when compared to the quarter with the highest intake. Eighty percent of American children and adolescents and 68% of adults do not eat five portions a day. Common micronutrient deficiencies are likely to damage DNA by the same mechanism as radiation and many chemicals, appear to be orders of magnitude more important, and should be compared for perspective. Remedying micronutrient deficiencies is likely to lead to a major improvement in health and an increase in longevity at low cost.
Nat Rev Cancer. 2002 Sep;2(9):694-704.
Are vitamin and mineral deficiencies a major cancer risk?
Ames BN, Wakimoto P.
Nutrition Genomics Center, Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr Way, Oakland, California 94609-1673, USA. bames@chori.orgDiet is estimated to contribute to about one-third of preventable cancers -- about the same amount as smoking. Inadequate intake of essential vitamins and minerals might explain the epidemiological findings that people who eat only small amounts of fruits and vegetables have an increased risk of developing cancer. Recent experimental evidence indicates that vitamin and mineral deficiencies can lead to DNA damage. Optimizing vitamin and mineral intake by encouraging dietary change, multivitamin and mineral supplements, and fortifying foods might therefore prevent cancer and other chronic diseases.
Lar
poster:Larry Hoover
thread:744072
URL: http://www.dr-bob.org/babble/alter/20070320/msgs/744102.html