Vitamin C Facts

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Myths and Facts


Preface

Foreword by Richard Passwater

Introduction Vitamin C – Past, Present and Future

Chapter 1 Vitamin C: The Difference between sickness and optimal health

Chapter 2 Myths and Facts

Chapter 3 Vitamin C and Ester-C metabolism and metabolites

Chapter 4 Vitamin C – The immune empowerer

Chapter 5 Vitamin C scavenges poisonous free radicals

Chapter 6 Fighter of heart disease and diabetes

Chapter 7 Vitamin C and arthritis

Chapter 8 Vitamin C and cancer

Chapter 9 Attack on viruses

Chapter 10 Vitamin C and metabolites kill the aids virus

Chapter 11 The new super C

Chapter 12 How much do you need?

Chapter 13 Vitamin C and optimal health

Bibliography


Rumours, Claims and Fantasy
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Which expert can you believe, especially when they are all so sincere? How can you know which "facts" to believe, which to question and which to dismiss as errant nonsense? These are far from trivial issues, especially in a saga as complex, long-standing and contradictory as that related to Vitamin C. Although it is not uncommon to have a majority of "experts" in any given scientific field at loggerheads and in intense competition with each other, it is not an everyday occurrence that a major scientific figure of a century with two Nobel prizes has to almost single-handedly "take on" the scientific and medical establishment in order to convince them of a substance's therapeutic efficacy. That Linus Pauling has to a large degree achieved this goal, in that the medical evidence in favour of Vitamin C's health enhancing properties is now overwhelming, is a tremendous testimonial of this man's foresight, tenacity and scientific wizardry.

However, what is the public to think when prominent and respected researchers disagree and contradict each other? Who can you believe and trust? Unfortunately, you have no choice but to exercise some human qualities like skepticism, discrimination and good old-fashioned common sense. This is actually what scientists are taught during their career - to always be critical, to always keep an open mind and to never get attached to the absolute truth of any theory. A safe bet is to regard the "truth" as the "best working hypothesis" of the day.

There has been a fair degree of criticism of the scientific and medical research establishment throughout this book, especially regarding the slow pace and minimal level of funding of research related to natural substances such as Vitamin C compared to more expensive and toxic drugs. However, be this as it may, there is still much to be said for the elaborateness of procedures of the scientific method, where eventually facts get unearthed and distinguished from erroneous hypotheses, conjectures and premises. This is not, however the case for articles appearing in the various media (newspapers, magazines, newsletters), which, not subjected to the rigid constraints of the scientific community, can run riot in sensationalism, panic mongering and elaborate fantasy, with the apparently well-intentioned motive of exposing dangerous facts. Below are several quotations from one such article(24), extremely convincingly written, and with interesting and speculative hypotheses and theoretical conclusions presented as irrefutable facts. The author alleges that Vitamin C may be responsible for CAUSING: infection, gum problems, depression, exhaustion, personality changes, blood Sugar problems, amongst many other things, including CANCER:

"You could take every book on vitamin C and throw it in the East River! You'll probably be a lot healthier for it";

"Vitamin C is lost from the body so readily because it causes dramatic physiological effects that could be dangerous";

"The inability to produce vitamin C internally may be one of the greatest things that has elevated human beings over animals. Vitamin C reduces copper levels, and the absence of internally produced ascorbic acid may have allowed a higher level of copper to exist in human brains. There is one species of dog, the Bedlington Terrier, who has extremely high levels of copper and who is so intelligent that some owners consider it to be "almost human";
"This confirms my suspicion that in some people - about 10-20 percent of the population, excess vitamin C can contribute to bone problems, ie osteoporosis";

"I know from my own experience that C supplements over 500 mg a day cause me extreme fatigue. I have also talked to two other people who had similar results";

Rather than literature citations, the author, a "publisher" speaks of his opinion, his suspicion, his experience. He cites NO research, merely speaking of his own subjective opinions, or that of several friends. It is outrageous that such serious, unsubstantiated allegations can be published; consider the potential harm such alarmist fantasy could do, while raising fears in the public. While personal experience is always to be valued, the discriminating consumer bears in mind that his own experience is as valid as the next, and that neither may represent the whole situation. Articles such as this are exceedingly provocative and as such are valuable in enabling us to look at the facts and our beliefs in a critical light; however, if the allegations are mistaken, unsubstantiated and believed by an uncritical reader, there is no scientific organization to which the author can be held accountable. No self-respecting scientist would dare to make such sweeping prognostications about complex physiological phenomena. Hence the eternally appropriate "caveat emptor" buyer beware for each of us.

Over the years Vitamin C has been implicated in causing certain conditions and interfering with certain diagnostic tests(99). These issues have recently been thoroughly reviewed by Cheraskin(54) and Pauling(166); an updated summary of the major concerns and latest evidence is hereby presented.

Vitamin C Causes Kidney Stones
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As indicated in Fig. 3 (Chapter 3), oxalic acid is one of the by-products of Vitamin C metabolism, and there has been a rather long-standing concern that consumption of large amounts of Vitamin C could cause the formation of calcium oxalate kidney stones. The clinical evidence(132,212-3), recently reviewed separately by Cheraskin(54), Pauling(166) and Rivers(178) indicate that, in fact, Vitamin C does NOT cause kidney stones in "normal" individuals(188). The several reported such cases involving Vitamin C indicate that oxalate metabolism and contributory factors to kidney stones are rather complicated: other factors include dietary oxalate consumption, low calcium and magnesium intake, EDTA consumption, B6 deficiency, high tryptophan, Vitamin D and sucrose, low water consumption and persistently acid urine. In fact, some research indicates that oxalate may actually be a minor component in kidney stone formation, in that some people with normal oxalate excretion make kidney stones, and others with large oxalate excretion do not(54). According to Rivers at the 3rd Int. Conference on Vitamin C, 1987 "ingestion of large quantities of the Vitamin (C) does not constitute a risk factor for calcium oxalate stone formation in most healthy persons".

Cheraskin(54) and Cathcart(49) have both pondered why Vitamin C does not seem to produce kidney stones, even though oxalate metabolism can be increased. Both these physicians, with clinical experience with many thousands of patients, have reached similar theoretical conclusions about why Vitamin C may actually PREVENT kidney stones:

1. Vitamin C makes the urine more acidic, thereby reducing the binding of calcium with oxalate;


2. Vitamin C binds calcium, thereby reducing calcium's free form, making it unavailable for binding with oxalate;
3. Vitamin C enhances the frequency of urination, making it less likely for stones to form;

4. Vitamin C is a mild urinary tract disinfectant, thereby reducing the focii of infections around which calcium oxalate cystals could be deposited.

There do appear to be individuals who may have a congenital defect in their oxalate metabolism and who are therefore prone to forming kidney stones. Since calcium oxalate stones form in acidic urine, using forms of Vitamin C which keep the urine alkaline such as sodium ascorbate may prevent these stones(166). Individuals with such a history or tendency should explore Vitamin C, and indeed, their entire supplementation programme, with a professional othomolecular physician. Individuals with a history of kidney stones, renal impairment and individuals on kidney dialysis should not ingest large amounts of Vitamin C unless under medical supervision(178). Further clinical research documenting the effects of the different forms of Vitamin C, including the mineral ascorbates and Ester-CR ascorbate would help to lay to rest this theoretical concern which has not materialized amongst the considerable populations of Vitamin C users.


Vitamin C Causes Gouty Arthritis
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Concerns that Vitamin C could cause gouty Arthritis in predisposed persons have not materialized; not a single report has appeared in the literature(54,166). In fact, Vitamin C has recently been proposed as a treatment for gout, due to its ability, with high doses, to lower serum uric acid levels. According to Rivers, "The evidence does not support claims for an ascorbic acid induced uricosuria"(178).


Vitamin C Destroys Vitamin B12
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The original report by Herbert & Jacob(102), alleging that Vitamin C destroys Vitamin B12, has been refuted by several reliable research studies(2,103,144-5,160). The study by Herbert & Jacob was severely flawed in that it contained errors in estimating the amount of Vitamin B 12 contained in food by a factor of 5. Again, Rivers(178): "The evidence has consistently demonstrated that Vitamin B12 in food and the body is not destroyed by ascorbic acid".


Vitamin C Causes Sterility
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The proposed hypothesis in the mid-1970's that Vitamin C might prevent conception and thus reduce fertility in women has not been substantiated, and has been refuted by physicians such as Abraham Hoffer(54). In fact, in experiments carried out in Japan and Ireland(54), it appears that Vitamin C may actually INCREASE fertility and aid in conception, in addition to regulating ovulation and controlling spontaneous abortion in pregnant women(166).

On the male side, research indicates that Vitamin C may enhance male fertility. A placebo controlled trial with 30 men conducted by Dawson and co-workers(66) indicated that Vitamin C improved sperm in terms of total count, viability, motility and reduced sperm agglutination.


Vitamin C Causes Iron Overload
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Vitamin C is one of the main promoters of dietary iron absorption, along with meat and fish(96). Vitamin C can form soluble iron complexes and reduce ferric to ferrous iron. The main dietary inhibitors of iron absorption are phytates found in pulses and polyphenols(96). Tea, and to a lesser extent, coffee, inhibit iron absorption(183). Vitamin C's enhancement of iron absorption is normally regarded as a positive attribute; nevertheless, concerns have been raised postulating that Vitamin C could have the effect of increasing iron absorption so much as to cause excessive iron or iron overload.
According to Rivers who recently reviewed the research evidence "the regulatory mechanisms that control body iron stores override any pronounced alterations in food iron availability...Concern that massive doses of ascorbic acid might lead to pressive iron accumulated in healthy iron-replete individuals appears unwarranted"(178).

In fact research indicates that Vitamin C can actually help to reduce excessive iron stores in individuals with iron-overload disorders. Such individuals have subnormal white blood cell levels of Vitamin C, caused by their excessive iron storage. When Vitamin C is administered to restore normal white cell levels excessive iron is excreted(231).

Therefore the evidence seems to point to Vitamin C having a pivotal homeostatic role with respect to iron - it promotes iron absorption in iron-deficient individuals and accelerates iron excretion in people with excessive iron.

Vitamin C Interferes with Serum Glucose Levels and Causes Diabetes
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Concerns that taking high doses of Vitamin C could affect serum glucose levels, interfere with diagnostic blood and urinary tests for glucose(148) and actually cause diabetes have prompted studies to assess Vitamin C's effect upon blood and urinary glucose levels.

Studies by Katz & Di Silvio(124), Prauer(170) and Spiegel & Pinili (194) clearly showed that serum glucose levels are not affected by Vitamin C, and that taking large doses of Vitamin C would not interfere with glucose blood tests. In order to determine whether Vitamin C could interfere with urinary glucose, especially important for diabetics, Nahata & McLeod(159) performed a total of 360 copper detection tests on 10 male subjects' urine samples, with 9 replicates per each of the 4 dosage regimes, ranging from 4-6 gm Vitamin C. Not a single false-positive reaction occurred. Tests have also been developed in which Vitamin C does not interfere with urinary glucose determinations(34).


Vitamin C Interferes with Blood Stool and Urinary Tests
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Jaffe and coworkers at the NIH reported in 1975(114) that ingesting large quantities of Vitamin C masks the detection of blood in stool samples, and, in 1979(115), of blood in urine, and for several years it was required to stop Vitamin C supplementation for 24-36 hours previous to having blood stool and urine tests performed. However, Dr. Jaffe, being a resourceful clinical pathologist in addition to a strong advocate of Vitamin C's therapeutic effects, went on to develop a new test for blood in the stool which is not interfered with by Vitamin C(116). However, until such time as a blood in urine detection test is developed which is not masked by Vitamin C, it will still be necessary to refrain from taking Vitamin C prior to taking such a diagnostic test.

Vitamin C Causes Rebound Scurvy
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Allegations that suddenly stopping Vitamin C after taking prolonged large doses could actually cause "rebound scurvy"(214) have been investigated in research studies. Hornig and co-workers, after administering massive doses of Vitamin C to guinea pigs over a prolonged period reported that results "disprove the hypothesis that the regular ingestion of large doses of ascorbic acid may lead to systemic conditioning, i.e., accelerated ascorbic acid metabolism or excretion due to a possible induction of the participating enzymes"(106).
Nevertheless, it is vital that Vitamin C NOT BE STOPPED SUDDENLY, especially with individuals with cancer and AIDS(43,48,166). A sudden depletion of that person's ascorbic acid level could massively lower their resistance, making them extremely vulnerable to infection and disease. When large doses of Vitamin C are taken, the entire enzymatic machinery, including metabolites, goes into operation(166). In this way, because of an adequate supply of ascorbic acid, more of Vitamin C is converted to metabolite products. If Vitamin C is suddenly withdrawn, the person's biochemistry will continue to produce these metabolites for a week or two, despite the fact that there is not an adequate Vitamin C level in the blood. Since Vitamin C is so vital for almost every body system, from brain to heart to the immune system, this can be exceedingly dangerous for severely ill persons.

For these reasons, it is most important that anyone who has been taking more than 5 gm Vitamin C daily on a maintenance dosage taper off gradually, if they decide to reduce their daily Vitamin C supplementation.


Summary of Vitamin C Safety Considerations
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As reported by Rivers in the 1987 Vitamin C Conference(178) "the practice of ingesting large quantities of ascorbic acid will not result in calcium oxalate stones, increased uric acid excretion, impaired Vitamin B12 status, iron overload, systemic conditioning or increased mutagenic activity in healthy individuals".

In other words, do not necessarily panic when reading alarming articles about the dangers of Vitamin C. They may not, and thus far in fact, have NOT been true. No reported case of a serious illness from Vitamin C exists, and in animal studies, administration of 1/2% body weight of Vitamin C produced no side effects. This amounts translates into 350 gm for a human being!


THE VITAMIN C NETWORK - MINERAL AND DRUG INTERACTIONS


The nature of the interaction of Vitamin C with other nutrients - vitamins and minerals, and drugs(176), is far from completely understood. In the summation report of Rivers at the most recent Vitamin C Conference in 1987(178) "The interaction of ascorbic acid with dietary essential mineral elements other than iron is not included in this review. Research on this topic is revealing interesting results, but is insufficient at this time to formulate valid conclusions".

Although there may not as yet be comprehensive knowledge regarding the interaction of Vitamin C and other nutrient elements and drugs, there have been to date, at least preliminary data demonstrating some of the complex synergistic actions of Vitamin C with other substances. These are summarised in Table 9 below:

Table 9: Interactions of Vitamin C with Other Nutrients
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Nutrient Vitamin C: Co-factors Ref.
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Calcium Assists in calcium absorption Mg, CT, PTH 93

Cadmium Reduces body burden of Cadmium Zinc 38,65

Chromium Alters toxic form of chromium

Copper May reduce copper levels 65,168

Cysteine May reduce levels of cysteine 65

Folic Acid Prevents destruction of folic acid 65

Iron Enhances absorption of iron 96

L-Carnitine Required for synthesis of L-Carnitine 135

Lead Reduces body burden of lead Copper, Zinc 38,65

Lysine May Reduce levels of lysine 65

Mercury Reduces body burden of mercury 38,65

Zinc May reduce levels of zinc; is a co-factor of
zinc in prostaglandin synthesis 65,91

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The above data is to be regarded as preliminary; in fact, an article by Calabrese et al(38) failed to show any effect at all of Vitamin C upon levels of cadmium, lead and mercury in 45 males over a 2 month period. However, these individuals had normal levels, and it would be more appropriate to study the effect of Vitamin C in individuals with a high body burden of these toxic metals.

Vitamin C and Drug Interactions
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Just as Vitamin C can modulate the action of certain drugs(25,173,192) (see Chapter 11), so can certain drugs affect Vitamin C's effects(93,99). It is emphatically suggested that individuals who are taking such medications become fully informed about the entire range of their side effects and metabolic interactions. A brief compilation of some of the major drugs and their interactions with Vitamin C is presented in Table 10:







Table 10: Vitamin C and Drug Interactions
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Drug Interaction with Vitamin C
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Alcohol Vitamin C detoxifies, prevents "hangover" and liver damage(245)

Aspirin Depletes Vitamin C levels, inhibits Vitamin C absorption(54,65)

Anti-coagulants Vitamin C decreases anti-coagulant effects(93)

Barbiturates Depletes Vitamin C levels. Vitamin C increases barbiturate
effects(93)

Heroin Vitamin C relieves withdrawal symptoms(79)

Methadone Vitamin C relieves withdrawal symptoms(79,187)

Oral Contraceptive Depletes Vitamin C levels(54)

Sulfa Drugs Decreases Vitamin C effects(93)

Tetracycline Decreases Vitamin C effects(93)

Tobacco Depletes Vitamin C levels(192). Smokers use 25 mg of Vitamin C per cigarette, which translates into 1/2 gm per pack.

Tranquillizers Vitamin C assists in withdrawal, reduces withdrawal side effects(54)

Vitamin C, Alcohol Detoxification and Relief of Hangovers
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Research investigating Vitamin C's ability to aid in detoxification following alcohol and drug abuse is one of the most promising avenues of research being pursued today (54,79,187). In a highly promising report prepared by Zannoni and co-workers(245) at the Third Conference on Vitamin C, Vitamin C was described as being able to oxidize alcohol in the following manner: Vitamin C generates a peroxide which is then used by catalase in the oxidation of alcohol. The body has an ascorbate-dependent detoxification system which is more active than the alcohol dehydrogenase or Cytochrome P-450 microsomal systems. In one study, whereas half the alcohol-dosed guinea pigs developed liver necrosis, none of the Vitamin C-treated animals developed liver damage.

In humans, Vitamin C was demonstrated to significantly enhance alcohol clearance, and even to effect substantial improvements in behaviour, especially motor coordination. And, since Vitamin C reduces fat accumulation in the liver following alcohol consumption, it appears that Vitamin C may protect against direct damage to the liver from alcohol.

Experiments for the Future
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It would appear to be self-evident that the interaction of Vitamin C, itself such a ubiquitous and complexly integral part of the entire body's biochemistry, with other equally complex vitamins and minerals, is not simple. Biochemistry and homeostatic metabolism normally provides for an elaborate system of feedback loops and safety valves, to ensure our proper functioning. Knowledge about how large doses of Vitamin C interact with other essential nutrients is eagerly awaited.

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