The power of vitamin C is often attributed to its role as an antioxidant. However, no other antioxidant can perform the many additional physiological and biological roles that vitamin C fills. To think of vitamin C as nothing more than an antioxidant would be a great understatement.

Among its many positive effects on the body, vitamin C is a strong supporter of healthy immune function. Here’s how:

  1. Vitamin C supports the production of interferons.  Interferons are produced when the presence of pathogens is detected. They facilitate the ability of cells to launch protective cellular defenses.
  2. Vitamin C enhances the function of phagocytes. Phagocytes are a type of white blood cell that envelop pathogens and other dangerous particles. Once the invaders are captured in this manner, they are enzymatically digested.
  3. Vitamin C is found mostly in white blood cells.  Some of the primary cells in the immune system contain levels of vitamin C as much as 80 times higher than the levels found in plasma.
  4. Vitamin C supports the cell-mediated immune response. There are 2 major ways that the body can respond to a pathogen: antibody-mediated immunity and cell-mediated immunity. Cell-mediated response refers to the activation of macrophages, natural killer cells, and antigen-specific T-lymphocytes that attack anything perceived as a foreign agent.
  5. Vitamin C enhances cytokine production by white blood cells. Cytokines are communication proteins released by certain white blood cells that transmit information to other cells, promoting the immune response.
  6. Vitamin C inhibits various forms of T-lymphocyte death.  T-lymphocytes are a type of white blood cell. They are an integral part of the cell-mediated immune defense system. Vitamin C helps to keep these important cells alive and viable.
  7. Vitamin C enhances nitric oxide production by phagocytes. Phagocytes, as discussed in #2 above, are white blood cells that engulf invading microorganisms. Nitric oxide is produced in large amounts in these cells, and it is one of the agents that will kill captured pathogens.
  8. Vitamin C enhances T-lymphocyte production.  As mentioned in #6 above, these cells are essential to cell-mediated immune responses, and vitamin C helps them to multiply in number.
  9. Vitamin C enhances B-lymphocyte production.  These white blood cells make antibodies as part of the antibody-mediated immune response. Antibodies are formed in reaction to the initial introduction of an invading pathogen or antigen.
  10. Vitamin C inhibits neuraminidase production.  Some pathogenic viruses and bacteria create neuraminidase, an enzyme that keeps them from being trapped in mucus, one of the body’s natural lines of defense. By inhibiting neuraminidase, vitamin C helps the body optimize this defensive mechanism.
  11. Vitamin C supports antibody production and activity.  Good antibody function is important to a healthy immune system.
  12. Vitamin C supports natural killer cell activity. Natural killer cells are small lymphocytes that can directly attack cells, such as tumor cells, and kill them.
  13. Vitamin C promotes prostaglandin formation.  Prostaglandins are hormone-like compounds that control a variety of physiologic processes, including the regulation of T-lymphocyte function.
  14. Vitamin C supports cyclic GMP levels in lymphocytes.  Cyclic GMP plays a central role in the regulation of different physiologic responses, including the modulation of immune responses. Cyclic GMP is important for normal cell reproduction and differentiation (specialization for specific purposes). Cyclic GMP also controls the action of many hormones, and it appears to mediate the relaxation of smooth muscle.
  15. Vitamin C supports localized generation of and/or interaction with hydrogen peroxide.  Vitamin C and hydrogen peroxide can kill microorganisms and can dissolve the protective capsules of some bacteria, such as pneumococci.
  16. Vitamin C detoxifies histamine.  This effect of vitamin C is important in the support of local immune factors.
  17. Vitamin C neutralizes oxidative stress.
  18. Vitamin C improves and enhances the immune response achieved with vaccination.
  19. Vitamin C enhances the mucolytic effect. This property helps liquefy thick secretions, increasing immune access to infection.
  20. Vitamin C may make bacterial membranes more permeable to some antibiotics.