Press Release

Thu Aug 12 09:41:21 EDT 2004

  1. Medline Plus at

    Report entitled: MEDLINE PLUS Update, Vitamin C, Date: 1/18/2003 by: Steven Angelo, M.D., Assistant Professor of Medicine, Yale School of Medicine, New Haven, CT. Review provided by VeriMed Healthcare Network.


    Falsely claims scurvy, a deficiency of vitamin C, is rare in the USA. "A deficiency of vitamin C causes the disease scurvy, which is rare in the United States."
    Falsely claims excessive doses of vitamin C "can lead to toxicity."
    Falsely claims vitamin C toxicity can produce kidney stones.
    Falsely claims high-dose vitamin C impairs absorption of vitamin B12. Many studies have disproven this claim. [Am J Clin Nutr. 1981 Jul;34(7):1356 -61; Am J Clin Nutr. 1976 Jun;29(6):645; Scott Med J. 1982 Jul;27(3):240-3]
    Accurately claims the "Recommended dietary allowances (RDAs) are defined as the levels of intake of essential nutrients that, on the basis of scientific knowledge, the Food and Nutrition Board judges to be adequate to meet the known nutrient needs of practically all healthy persons," but fails inform the public that the current RDA meets the vitamin C needs of few if any Americans.
    Mistakenly advises the best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods from the food guide pyramid. The food pyramid has since been re-done twice since the RDA for vitamin C was established. The most common plant foods consumed by Americans (in order - iceberg lettuce, tomatoes, French fries, orange juice and onions) provide little vitamin C.

  2. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) at

    Report entitled: 200 Milligrams Daily of Vitamin C is Appropriate, April 15, 1996 press release


    Mistakenly claims 200 milligrams is all that is needed by healthy individuals.

    Advocates the consumption of five servings of fruits and vegetables to obtain 200 mg of vitamin C. But the National Cancer Institute now advocates 9 servings of fruits and vegetables based upon the fact that 5 servings did not lower the risk for heart disease or cancer.

    Misleads consumers into thinking high-dose vitamin C causes kidney stones.
    Mistakenly claims 200 milligrams of vitamin C saturates the blood plasma. The saturation studies for vitamin C were performed 12 hours after oral ingestion of vitamin C without calculating for the half life of the vitamin. The half life (when half of the dose is gone) for vitamin C is 30 minutes, so measuring blood plasma saturation 12 hours (or 24 half lives) following oral ingestion, is a patently bogus methodology. See S. Hickey, H. Roberts, Ascorbate: The Science of Vitamin C, available at

  3. National Institute of Diabetes and Digestive and Kidney Diseases, press release of April 20, 1999 at

    Report entitled: NIH Research Shows 100 to 200 Mg of Vitamin C Daily May Benefit Healthy Adults, April 20, 1999


    Indicates "The RDA is based on the amount of vitamin C needed to prevent scurvy, a potentially fatal disease marked by fatigue and bleeding," but fails to mention amounts of vitamin C needed for optimal health.
    Errantly states "Our work reinforces the health message that healthy people should be eating five servings of a variety of fruits and vegetables every day. You'll get adequate vitamin C and you have the potential benefit of preventing disease, especially certain cancers." The National Cancer Institute concedes that 5 servings of fruits and vegetables a day has not reduced the risk of cancer and heart disease and now advocates nine servings a day.
    Without substantiation, makes the false claim that "healthy people are better off eating fruits and vegetables rather than relying on supplements because absorption of the vitamin in supplements varies widely, depending on manufacturing methods and the dose taken."
    Makes the false claim that "at 1,000 mg, some volunteers showed high levels of oxalate and uric acid in their urine, which might lead to kidney stones." The levels of oxalate in studies were only marginally higher and other studies dispel the idea that vitamin C pill increase the risk for kidney stones.
    Makes the inaccurate claim that "at 200 mg, blood plasma had more than 80 percent maximal concentration of vitamin C, and tissues were completely saturated." Recent studies performed by National Institutes of Health researchers themselves indicates blood plasma concentrations of vitamin C can increase three times beyond the mythical "saturation point."

  4. Quackwatch at uack.html

    Report entitled: Twenty-Five Ways to Spot Quacks and Vitamin Pushers
    By Stephen Barrett, M.D. and Victor Herbert, M.D., J.D.


    Falsely maintains the diet provides all the nutrients necessary to maintain health.
    Mistakenly claims that health quacks claim that the Recommended Dietary Allowances (RDAs) Have Been Set Too Low because then "you are more likely to buy supplements."
    Claims anyone who recommends dietary supplements are "beneficial for everyone" is a health quack.
    Falsely claims "no normal person following the U.S. Dietary Guidelines is in any danger of vitamin deficiency."

  5. Merck Manual at

    Report entitled: Vitamin and Trace Mineral Disorders; vitamin C, Merck M anual of Geriatrics, Chapter 60.


    Mistakenly claims doses "greater than 1000 mg daily are not recommended" because vitamin C increases iron absorption and high levels of iron may be associated with an increased risk of cardiac disease. "Another concern about consuming high doses of any antioxidant is that under certain conditions, antioxidants can have the opposite effect (ie, can become a pro-oxidant) and perhaps damage cells and DNA." Vitamin C supplements do not induce iron overload and do not cause DNA damage in humans. [Science. 2001 Sep 14;293 (5537):1993-5; Int J Vitam Nutr Res. 1999 Mar;69(2):67-82]

  6. Mayo Clinic website at

    Report entitled: Mayo Clinic, Ascorbic Acid (Vitamin C) DR202071; May 01, 19 95
    By Micromedex Inc.


    Claims that the "increased need for vitamin C should be determined by your health care professional." There are few if any health professionals who understand how to estimate the body's increased need for vitamin C.
    Mistakenly claims that the "the RDAs for a given nutrient may vary depending on a person's age, sex, and physical condition (e.g., pregnancy)." The RDA is calculated for healthy persons only and is not adjusted for age or physical condition.

    Blood problems-High doses of vitamin C may cause certain blood problems
    Misleads consumers into believing high-dose vitamin C is potential harmful for diabetics because it "may interfere with tests for sugar in the urine." High-dose vitamin C may reduce blood sugar levels which certainly does alter tests, but in a beneficial manner.

    Continues to spread the false claim that "high doses of vitamin C may induce kidney stones." [J Am Society Nephrology 1999 Apr;10(4):840-5; Nutrition Reviews 1999 Mar;57(3):71-7; Clin Chem Laboratory Medicine. 1998 Mar;36(3):143-7; Annals Nutrition Metabolism. 1997;41(5):269-82]

  7. at at

    Report entitled: Vitamin C Capable Of Damaging DNA


    Continues to post a Reuters Health report dated June 14, 2001, based upon a study published in Science magazine which erroneously claimed that high-dose vitamin C damages DNA and could cause cancer. [Science 2001;292:2083-2086] This report was rebutted in a later issue of Science magazine. [Science. 2001 Sep 14;293 (5537):1993-5]

  8. WebMDd at based on a report from Duke at

    Report entitled: Vitamin C Worsens Knee Osteoarthritis in Animal Study
    Researchers Say Dietary Intake Should Not Be Above the RDA Recommendation
    By Jennifer Warner, WebMD Medical News. Reviewed By Brunilda Nazario, MD

    Research by Virginia Kraus, MD. Collaborators on the study include Janet Huebner, Thomas Stabler, Charlene Flahiff, Loria Setton, Christian Fink and Amy Clark, all of Duke.

    Published the results of an animal study conducted at Duke University which concluded that high-dose vitamin C may induce osteoarthritis without checking on the validity of this report nor publishing any contrary opinions. [Arthritis Rheumatism June 2004] In fact, a large, long-term human study published 8 years earlier showed that humans who consume the most vitamin C are three times less likely to develop osteoarthritis. [Arthritis Rheumatism 1996 April;39: 648-56] WebMD makes the false claim that "this new study shows prolonged use of vitamin C supplements may aggravate osteoarthritis," when in fact this has never been demonstrated in humans.

  9. Personal MD at

    Report entitled: High Doses Of Vitamin C May Be Harmful


    Continues to post a bogus Reuters News story based on a report in Nature Magazine [Nature, April 9, 1998;392:559], based on a test-tube study, that high -dose vitamin C may damage DNA. At least five human study disprove this idea. [Science. 2001 Sep 14; 293 (5537):1993-5]

  10. at

    Report entitled: Additional Information about Products Approved in Testing

    States: "Vitamin C supplementation should not exceed 2,000 mg/day. Dosages above this established upper limit may cause diarrhea and intestinal gas." There is no study which shows the oral vitamin C above 2000 milligrams produces intestinal gas or diarrhea. It is known that there is a variable dosage where diarrhea occurs, called the bowel tolerance point. Diarrhea may not occur in some people who take more than 20,000 milligrams of oral vitamin C.

Bill Sardi authored and Owen Fonorow contributed to this report.

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