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Orthomolecular Medicine News Service, March 19, 2008

Vitamins Reduce the Duration and Severity of Influenza

(OMNS, March 19, 2008) Vitamins fight the flu by boosting the bodyís own immune response and by accelerating healing. Individuals can be better prepared for an influenza epidemic by learning how to use vitamin supplements to fight off ordinary respiratory infections. The most important vitamins are vitamins C, D, niacin, and thiamine.

Vitamin D
Vitamin D has known anti-viral properties [1] and has been directly associated with fighting influenza in a recent scientific review. [2] Extensive evidence now shows that vitamin D serves as an important regulator of immune system responses. [3] The most dramatic evidence is a recent double-blind trial proving that vitamin D prevents cancers [4], supported by two recent epidemiological studies. [5,6] Vitamin D has been part of a supplement combination proven effective against HIV in a recent double-blind trial. [7]

During a viral infection, the body can draw on vitamin D stored in the body to supply the increased needs of the immune system. The withdrawn supplies of vitamin D are quickly replenished with 4,000 to 10,000 IU/day doses for a few days. Due to biochemical individuality, we recommend vitamin D blood testing as a routine part of a yearly physical exam.

Niacin has known anti-viral properties. The most persuasive evidence comes from recent work with HIV patients.[8-12] Niacin is required for cells to generate the energy they use to perform virtually all biological functions.

Niacinís effectiveness fighting viruses may have to do with accelerating wound healing as well as improving immunity. Accelerating tissue repair limits collateral damage and minimizes the risk of secondary infection. Niacin has been proven to promote healing of damaged skin in double-blind trials. [13] Other recent findings (niacin reduces injury to the brain after strokes and reduces inflammation in general) also provide evidence of healing. [14,15]

Niacin, 500 to 2,000 mg/day in divided doses, is generally well tolerated during periods when the immune system is fighting viral infections. One takes such doses for several days starting at the onset of a viral infection. Dividing the dose reduces flushing. Using "no-flush" form niacin (inositol hexaniacinate) eliminates the flushing side effect.

Vitamin C
Strong evidence shows that high doses of vitamin C prevent common colds and reduce a coldís severity and duration. [16] Given the similarities between cold and influenza viruses, the scientific case for treating influenza with vitamin C has been investigated and shown to have merit. [17] Fighting influenza with vitamin C has been tested in the clinical setting and reported to be effective at very high doses. [18, 19]

Extraordinary quantities of vitamin C, between 20,000 and 100,000 mg/day, are surprisingly well tolerated during periods when the immune system is fighting viral infections. These large daily amounts are best taken divided up into as many doses per day as possible, beginning immediately at the first sign of a viral infection. To achieve maximum effect it is necessary to maintain high concentrations of vitamin C in the body. Large, very frequent oral intake of vitamin C can maintain much higher blood plasma concentrations of vitamin C than is generally believed. [16, 19, 20]

Thiamine (Vitamin B1)
Two items of recent scientific research have shown that the B-vitamin thiamine has anti-viral properties. TTFD, one of the fat-soluble forms of thiamine, was recently proven to be a potent inhibitor of HIV virus replication [21]. Thiamine was shown to be an effective treatment for chronic hepatitis B. [22]

Influenza killed more people in the two years following World War I than all soldiers killed on both sides in four years of machine-gun warfare. Influenza has been and remains a serious threat to human health. There is a great deal of public concern about the possibility of a repeat of the 1918 influenza pandemic. Vitamin C, niacin, vitamin D, and thiamine act together to strengthen the immune system, and to optimize health. Intelligent, high-dose vitamin supplement use can do much to eliminate the risk of death and disability for individuals with average health, and dramatically reduce the hospitalization and death rates amongst the most vulnerable members of the population.



[2] Cannell JJ et al. Epidemic influenza and vitamin D. Epidemiology and Infection. 2006. Dec;134(6):1129-40. Free access to full text paper at

[3] Tavera-Mendoza LE, White JH. Cell defenses and the sunshine vitamin. Scientific American, November 2007, 62-72.

[4] Lappe JM et al. Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. Am J Clin Nutr. 2007 Jun;85(6):1586-91.

[5] Abbas S, et al. Serum 25-hydroxyvitamin D and risk of postmenopausal breast cancer - results of a large case-control study. Carcinogenesis. 2008 Jan;29(1):93-9.

[6] Freedman DM et al. Prospective study of serum vitamin D and cancer mortality in the United States. J Natl Cancer Inst. 2007. Nov 7;99(21):1594-602.

[7] Kaiser JD et al. Micronutrient supplementation increases CD4 count in HIV-infected individuals on highly active antiretroviral therapy: A prospective, double-blinded, placebo-controlled trial. Journal of Acquired Immune Deficiency Syndromes, 2006. 42(5), 523-528. "Micronutrient supplementation can significantly improve CD4 cell count reconstitution in HIV-infected patients. . . "

[8] Murray MF. Niacin as a potential AIDS preventive factor. Medical Hypotheses, 1999. 53(5), 375-379.

[9] Murray MF, Langan M, MacGregor RR. Increased plasma tryptophan in HIV-infected patients treated with pharmacologic doses of nicotinamide. Nutrition (NY), 2001. 17(7/8), 654-656.

[10] Murray MF. Treatment of retrovirus induced derangements with niacin compounds. The Foundation for Innovative Therapies, Inc., USA, 2006. 9 p. US 7012086.

[11] Pero RW. A method for increasing tryptophan and nicotinamide levels in vivo, and therapeutic and monitoring methods. Lynpete Trading 6 Pty., Ltd. Trading as Genetic Health Enterprises, S. Afr. PCT Int. Appl. 2008, 73pp. WO 2008008837 A2 20080117

[12] Dube MP et al. Safety and efficacy of extended-release niacin for the treatment of dyslipidaemia in patients with HIV infection: AIDS clinical trials group study A5148. Antiviral Therapy, 2006. 11(8), 1081-1089. "(D)doses up to 2,000 mg daily was safe, well-tolerated and efficacious in HIV-infected subjects. . . "


[14] Maynard KI. Natural neuroprotectants after stroke. Science & Medicine, 2002. 8(5), 258-267.

[15] Yu, Bi-lian; Zhao, Shui-ping. Anti-inflammatory effect is an important property of niacin on atherosclerosis beyond its lipid-altering effects. Medical Hypotheses, 2007. 69(1), 90-94.

[16] Hickey S, Roberts H. Ascorbate: The science of vitamin C. 2004. Lulu Press. ISBN 1-4116-0724-4. Reviewed at


[18] Ely JT. Ascorbic acid role in containment of the world avian flu pandemic. Experimental Biology and Medicine, 2007. 232(7), 847-851.

[19] Cathcart RF. Vitamin C, titrating to bowel tolerance, anascorbemia, and acute induced scurvy. Med Hypotheses. 1981 Nov;7(11):1359-76. Free access to full text paper at See also: Cathcart RF. The third face of vitamin C. Journal of Orthomolecular Medicine, 7:4;197-200, 1993. Free access at or

Other Cathcart papers posted at and

[20] Duconge J et al. Pharmacokinetics of vitamin C: insights into the oral and intravenous administration of ascorbate. PR Health Sciences Journal, 2008. 27:1, March.

[21] Shoji, Shozo et al. Thiamine disulfide as a potent inhibitor of human immunodeficiency virus (type-1) production. Biochemical and Biophysical Research Communications, 1994. 205(1), 967-75. "The results suggest that thiamine disulfide may be important for AIDS chemotherapy."

[22] Wallace AE, Weeks WB. Thiamine treatment of chronic hepatitis B infection. American Journal of Gastroenterology, 2001. 96(3), 864-868.

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