Free radicals (although this term has a specific chemical meaning, it is being used to refer to a general class of small and highly reactive chemical substances of which the OH radical is the most prevalent) have been much in the news in recent years because the free radical theory of degenerative disease and aging is currently popular.
The general idea is that metabolically generated free radicals damage biologically important structures and lead to degenerative diseases and death."Antioxidants'' (substances that react with free radicals) have, therefore, become popular dietary supplements.
Although this is a fad that has yet to be proved beneficial, it may be correct and is easily reconciled with the observed beneficial effects of free radicals from ionizing radiation. Free radicals may be good for health in small amounts and bad for health in large amounts.
Especially interesting in this context is Vitamin C. Since Vitamin C is required for life (in very small amounts on the order of several milligrams per day), has been widely advocated for over 50 years as a health supplement in quantities of a gram or two per day, and is a chemical reducing agent, it is included in the list of antioxidant, free-radical trapping agents currently popular as dietary supplements.
Remarkably, however, Vitamin C is itself a very potent
source of free radicals (See S. L. Richheimer and A. B. Robinson, Orth. Psych. 6, pp 290-299 (1977) and references therein.) Vitamin C oxidation products react vigorously and destructively with proteins, DNA, and other biological macromolecules!I suggest that (if we assume that the nutrition folklore is correct in advocating a gram or two per day of Vitamin C - a subject that is still vigorously debated) the beneficial effects of Vitamin C may be primarily a result of damage done by its oxidation products to biological macromolecules - that the health benefits of Vitamin C are quite similar to the benefits demonstrated by Cohen, Luckey, and their colleagues for low-level nuclear radiation. (As far as I am aware this is an original hypothesis, although the publications by Richheimer and me in the 1970s contain similar suggestions.) The implications of these possibilities are remarkable. The health benefits of low-level radiation appear to be very substantial. Cohen finds, for example, (see
Access to Energy 21-4, December 1993) that lung cancer varies over a two-fold range as a function of home radon level - the higher radon levels having the lower cancer rates. It appears that the free-radical levels in human tissues should be adjusted for optimum health - not too high and not too low (but higher than currently exist in many people). This would be difficult to do with nuclear radiation because of the currently prevailing political climate, but it would not be difficult at all to do with Vitamin C.
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Vol. 22, No. 2
Newsletter: Access to Energy Newsletter Archive Volume: Issues Issue/No.: Vol. 22, No. 2 Date: November 01, 1994 02:19 PM Title: Optimism vs. Pessimism
Copyright © 2004 - Access to Energy Newsletter Archive
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