Vitamin C pp 125-133 | Cite as

The Safety of High Doses of Vitamin C

  • A. T. Diplock
Conference paper


For many years, some scientific experts, and some physicians, have advocated taking large doses of vitamin C, which has been thought to be protective against the common cold and other virus infections. Such dosages are considerably in excess of the recommended daily allowance (RDA) for the vitamin. More recently the indisputable properties of vitamin C as an antioxidant and free radical scavenger have been of particular interest as public attention has been focused on the possible association of enhanced intakes of antioxidants with lowered risk of degenerative diseases, notably some forms of cancer and cardiovascular disease. For all these reasons many members of the public take quite large supplements of vitamin C in the belief that this will provide health benefit. There is, however, not as yet substantiated scientific and medical evidence that this practice will result in lowered disease risk or any therapeutic benefit. It is thus essential that the ingestion of large doses of vitamin C does not carry with it any proven detrimental effects which might have the opposite consequence from that which is expected.


Urinary Oxalate Recommended Daily Allowance Body Iron Store Urinary Oxalate Excretion Uric Acid Excretion 
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  1. 1.
    Hanck A (1982) Tolerance and effects of high doses of ascorbic acid. Dosis facit venenum. Int J Vitam Nutr Res Suppl 23:221–238PubMedGoogle Scholar
  2. 2.
    Rivers JM (1989) Safety of high-level vitamin C ingestion. Int J Vitam Nutr Res Suppl 30:95–102PubMedGoogle Scholar
  3. 3.
    Diplock AT (1995) Safety of antioxidant vitamins and beta-carotene. Am J Clin Nutr 62[Suppl 6]:S1510-S1516Google Scholar
  4. 4.
    Bendich A, Langseth L (1995) The effects of vitamin C supplementation: a review. J Am Coll Nutr 14:124–136PubMedGoogle Scholar
  5. 5.
    Bendich A (1997) Vitamin C safety in humans. In: Packer L, Fuchs K (eds) Vitamin C in health and disease. Dekker, New York, pp 367–369Google Scholar
  6. 6.
    Kallner A, Hartmann D, Hornig D (1979) Steady-state turnover and body pool of ascorbic acid in man. Am J Clin Nutr 32:530–539PubMedGoogle Scholar
  7. 7.
    Levine M, Conry-Cantilena C, Wang Y et al (1996) Vitamin C pharmacokinetics in healthy volunteers: evidence for a recommended dietary allowance. Pro Natl Acad Sci USA 93(8): 3704–3709CrossRefGoogle Scholar
  8. 8.
    Schmidt KH, Hagmaier V, Hornig DH, Vuilleumier JP, Rutishauser G (1981) Urinary oxalate excretion after large intakes of ascorbic acid in man. Am J Clin Nutr 34:305–311PubMedGoogle Scholar
  9. 9.
    Wandzilak TR, D’Andre SD, Davis PA, Williams HE (1994) Effect of high dose vitamin C on urinary oxalate levels. J Urol 151(4):834–837PubMedGoogle Scholar
  10. 10.
    Mitch WE, Johnson MW, Kirshenbaum JM, Lopez RE (1981) Effect of large oral doses of ascorbic acid on uric acid excretion by normal subjects. Clin Pharmacol Ther 29:318–321PubMedCrossRefGoogle Scholar
  11. 11.
    Berger L, Gerson CD, Yu TF (1977) The effect of ascorbic acid on uric acid excretion with a commentary on the renal handling of ascorbic acid. Am J Med 62:71–76PubMedCrossRefGoogle Scholar
  12. 12.
    Herbert V, Hacob E (1974) Destruction of vitamin B12 by ascorbic acid. J Am Med Assoc 230:241–242CrossRefGoogle Scholar
  13. 13.
    Newmark HL, Scheiner J, Markus M, Prabhudesai M (1976) Stability of vitamin B12 in the presence of ascorbic acid. Am J Clin Nutr 29:645–649PubMedGoogle Scholar
  14. 14.
    Markus M, Prabhudesai M, Wassef S (1980) Stability of vitamin B12 in the presence of ascorbic acid in food and serum: restoration by cyanide of apparent loss. Am J Clin Nutr 33:564–569Google Scholar
  15. 15.
    Cook JD, Watson SS, Simpson KH, Lipschitz DA, Skikne BS (1984) The effect of high ascorbic acid supplementation on body iron stores. Blood 64:721–726PubMedGoogle Scholar
  16. 16.
    Cochrane HA (1965) Overnutrition in prenatal life: a problem. Can Med Assoc J 93:893–899PubMedGoogle Scholar
  17. 17.
    Rhead WA, Schrauzer GN (1971) Risks of long-term ascorbic acid overdosage. Nutr Rev 29:262–263PubMedGoogle Scholar
  18. 18.
    Norkus EP, Rosso P (1975) Changes in the ascorbic acid metabolism of the offspring following high maternal intake of this vitamin in the pregnant guinea pig. Ann NY Acad Sci 258:401–409PubMedCrossRefGoogle Scholar
  19. 19.
    Norkus EP, Rosso P (1981) Effects of maternal intake of ascorbic acid on the postnatal metabolism of this vitamin in the guinea pig. J Nutr 111:624–630PubMedGoogle Scholar
  20. 20.
    Halliwell B, Gutteridge JMC (1989) Free radicals in biology and medicine, 2nd edn. Clarendon, OxfordGoogle Scholar
  21. 21.
    Liebovitz B (1993) Editorial. J Optimal Nutr 2:140–141Google Scholar
  22. 22.
    Berger TM, Polidori MC, Dabbagh A et al (1997) Antioxidant activity of vitamin C in iron-overloaded human plasma. J Biol Chem 272:15656–15660PubMedCrossRefGoogle Scholar
  23. 23.
    Collis CS, Yang M, Peach SJ, Diplock AT, Rice-Evans C (1996) The effects of ascorbic acid and iron co-supplementation on the proliferation of 3T3 fibroblasts. Free Radical Res 25:87–93CrossRefGoogle Scholar
  24. 24.
    Collis CS, Tang M, Diplock AT, Hallinan T, Rice-Evans C (1997) Effects of co-supplementation of iron with ascorbic acid on antioxidant-prooxidant balance in the guinea pig. Ree Radical Res 27:113–121Google Scholar
  25. 25.
    Collis CS, Yang M, Kelly M et al (1998) The effects of iron and vitamin C co-supplementation on platelet function, oxidative damage to DNA and LDL peroxidizability in healthy volunteers. Biochem Biophys Res Commun (in press)Google Scholar
  26. 26.
    Podmore ID, Griffiths HR, Herbert KE, Mistry N, Mistry P, Lunec J (1998) Vitamin C exhibits pro-oxidant properties. Nature 392:559PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Italia, Milano 1998

Authors and Affiliations

  • A. T. Diplock
    • 1
  1. 1.International Antioxidant Research Centre, The Medical and Dental School of Guy’s, Kings’s and St. Thomas’s HospitalsGuy’s HospitalLondonUK

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