Zinc is an essential mineral with wound-healing, antioxidant, and immunity functions. Zinc has superior efficacy when used in gum, as it coats the throat and provides a barrier. It has been hypothesized that zinc blocks the binding of Rhinovirus (a common cold virus) to the ICAM-1 receptor, which thereby reduces the duration and severity of cold symptoms (7,8). A recent review of the literature concluded that zinc given within 24 hours of onset of cold symptoms, reduces the duration and severity of a cold (9). Furthermore, it was found that supplementation with zinc for at least 5 months decreased colds and school absenteeism in children (9). Zinc deficiency can impair your immune cells, such as macrophages, neutrophils, B-Cells, and natural killer cells (5,6). Zinc is required to activate T-lymphocytes (5).
Vitamin C was made famous by the Nobel Prize Winner Linus Pauling. He believed that Vitamin C reduced the incidence of Colds (1). There is some evidence to support the view that taking Vitamin C daily reduces the number of colds you contract (2). Other studies have shown a more substantial reduction in duration of cold episodes in athletes, and those exposed to cold temperatures (3). Supplementation with Vitamin C was found to improve components of the immune system, such as lymphocytes, anti-bacterial, and natural killer cell activities (4). Vitamin C also is an antioxidant, protecting the body from free radicals, which may damage your DNA.
Eleuthero (Siberian Ginseng) is an adaptogen that has been used for hundreds of years in China and Russia. An adaptogen is an herb that is thought to bring the body back into balance, and help it cope with mental or physical stress. It has been used in Russia and China to improve Energy and Immune function. A Study by Kan Jang of the Swedish Herbal institute showed that Siberian Ginseng improved symptoms of the common cold when started within 72 hours of symptom onset (10). Another study demonstrated antiviral activity towards some common cold viruses (11). A third study showed an increase in immunocompetent cells, such as T-lymphocytes, and natural killer cells (12). Lastly, a study showed to markedly increase immune system signaling markers (13).
Elderberry has been used for many years to treat wounds and colds. In Europe, Elderberry is used to treat colds and flu. Elderberry contains flavonoids, which are excellent antioxidants. Elderberry Extract was shown to activate the immune system by stimulating a broad range of cytokine messengers (14). There is also evidence to support that Elderberry reduces the duration of Flu symptoms (15).
Echinacea is herb that was used by Native Americans for hundreds of years to treat infections. It is still very popular in the U.S. and Europe. Some studies have shown Echinacea to activate the immune system, and work as an antioxidant. A recent combined analysis of studies showed a 58% decrease in the odds of developing the common cold (16). Echinacea has also been found to stimulate immune cells in a laboratory (17).
Astragalus is an adaptogen that has been used in Chinese Medicine for thousands of years. An adaptogen is an herb that is thought to bring the body back into balance, and help it cope with mental or physical stress. In Chinese Medicine, Astragalus is used to protect and support the immune system. Astragalus was shown in a lab to activate immune cells, such as B-Cells and Macrophages (18). Another study showed enhanced antibody and T-helper cell immune activity (19). A third study demonstrated activation of immune cells called macrophages (20). Lastly, it is also an antioxidant, protecting the body from free radicals.
(1) Pauling L. The significance of the evidence about ascorbic acid and the common cold. Proc Natl Acad Sci U S A 1971;68:2678-81
(2) Douglas RM, Hemilä H. Vitamin C for preventing and treating the common cold. PLoS Med 2005;2:e168.
(3) Douglas RM, Hemilä H, Chalker E, Treacy B. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev 2007;(3):CD000980
(4) Wintergerst ES, Maggini S, Hornig DH. Immune-enhancing role of vitamin C and zinc and effect on clinical conditions. Ann Nutr Metab 2006;50:85-94
(5) Shankar AH, Prasad AS. Zinc and immune function: the biological basis of altered resistance to infection.
Am J Clin Nutr 1998;68:447S-63S.
(6) Wintergerst ES, Maggini S, Hornig DH. Contribution of selected vitamins and trace elements to immune function.
Ann Nutr Metab 2007;51:301-23.
(7) Hulisz D. Efficacy of zinc against common cold viruses: an overview.
J Am Pharm Assoc (2003) 2004;44:594-603
(8) Caruso TJ, Prober CG, Gwaltney JM Jr. Treatment of naturally acquired common colds with zinc: a structured review.
Clin Infect Dis 2007;45:569-74
(9) Singh M, Das RR. Zinc for the common cold. Cochrane Database of Systematic Reviews 2011, Issue 2.
(11) Glatthaar-Saalmuller Bernadette, F. Sacher, A. Esperester. Antiviral activity of an extract derived from roots of Eleutherococcus senticosus. Antiviral Research. 2001; 50(3): 223-228.
(12) Bohn B., CT. Nebe, C. Birr. Flow-cytometric studies with Eleutherococcus senticosus extract as an immunomodulatory agent. Arzneimittelforschung. 1987; 37(10): 1193-6.
(13) Schmolz, M.W., F. Sacher, B. Aicher. The synthesis of Rantes, G-CSF, IL-4, IL-5, IL-6, IL-12 and IL-13 in human whole-blood cultures is modulated by an extract from Eleutherococcus senticosus L. roots. Phytotherapy Research. 2001; 15(3): 268-270.
(14) Barak V, Halperin T, Kalickman I. The effect of Sambucol, a black elderberry-based, natural product, on the production of human cytokines: I. Inflammatory cytokines. Eur Cytokine Netw. 2001 Apr-Jun;12(2):290-6.
(15) Zakay-Rones Z, Thom E, Wollan T, Wadstein J. Randomized study of the efficacy and safety of oral elderberry extract in the treatment of influenza A and B virus infections. J Int Med Res. 2004;32:132-40.
(16) Shah SA, Sander S, White CM, Rinaldi M, Coleman CI. Evaluation of echinacea for the prevention and treatment of the common cold: a meta-analysis. Lancet Infect Dis. 2007;7(7):473-80. Review.
(17) Vinti Goel, Chuck Chang, Jan V Slama, Richard Barton, Rudolf Bauer, Roland Gahler, Tapan K Basu . Echinacea stimulates macrophage function in the lung and spleen of normal rats. The Journal of Nutritional Biochemistry – August 2002 (Vol. 13, Issue 8, Pages 487-492)
(18) Shao BM, Xu W, Dai H, et al. A study on the immune receptors for polysaccharides from the roots of Astragalus membranaceus, a Chinese medicinal herb. Biochem Biophys Res Commun. 2004;320(4):1103-1111.
(19) Zhao K.S., C. Mancini, G. Doria. Enhancement of the immune response in mice by Astragalus membranaceus extracts. Immunopharmacology. 1990; 20(3): 225-233.
(20) Lee K.Y., Young Jin Jeon. Macrophage activation by polysaccharide isolated from Astragalus membranaceus. International Immunopharmacology. 2005; 5(7-8): 1225-1233.