Vitamin C and Immune Support

Vitamin C and Immune Function

Vitamin C has long been a means for enhancing the immune system and supporting the body during periods of inflammation, infection and disease (Klenner, 1949; Iqbal, Khan, & Khattak, 2004) such as:

  • Viral infections (e.g. colds, flu, pneumonia, herpes, shingles, hepatitis, HIV),
  • Bacterial infections (e.g. Helicobacter pylori, E. coli),
  • Allergies and asthma,
  • Chronic fatigue and glandular fever,
  • Arthritis,

Vitamin C deficiency is a common factor in many chronic and acute illnesses (Buffinton, & Doe, 1995; Long, Maull, & Krishnan, 2003). Vitamin C is important for promoting the function of immune cells and protecting them from oxidation, and has an anti-bacterial and anti-viral effect via interaction with metal ions creating a pro-oxidant environment that kills or inactivates pathogens through the production of high levels of hydrogen peroxide (Furuya, et al., 2008; Strohle, Wolters, & Hahn, 2011).

Intravenous Vitamin C (IVC) Therapy

Critical illness involves extreme oxidative stress, especially in the cardiovascular system, and several clinical trials have observed that high doses of vitamin C may lead to more positive outcomes (Nathens, et al., 2002; Biesalski, & McGregor, 2007). Serious acute infections such as pancreatitis may respond rapidly to vitamin C, with blood parameters and biomarkers of oxidative stress returning to normal quickly and a reduction of symptoms, complications and time spent hospitalised (Du, et al., 2003). Likewise, patients that have suffered from sepsis (Wilson, 2009) or significant trauma such as severe burns may also have a better recovery with vitamin C (Tanaka, et al., 2000).

Intravenous doses of up to 1.5g/kg have been given to humans with few adverse events (Hoffer, et al., 2008; Padayatty, et al., 2010). Most adverse events associated with IVC are transient and mild (such as diarrhoea, headache, fatigue), however for people with glucose-6-phosphate dehydrogenase (G6PD) deficiency, high doses of vitamin C could cause hemolysis so should be avoided (Campbell, Steinberg, & Bower, 1975).

There have been concerns that high doses of vitamin C may increase the risk of kidney stones, as one of the byproducts of vitamin C metabolism is oxalic acid which can form calcium oxalate deposits (Massey, Liebman, & Kynast-Gales, 2005). However, some studies may have exaggerated the risk by using analysis methods that cause conversion of vitamin C to oxalate. When people with normal renal function receive IVC and urine samples are processed appropriately, less than 0.5% of the vitamin C is converted (Robitaille, et al., 2009). However, as a precaution, people with impaired renal function or a history of stone formation should be monitored carefully.

The information provided here is only for general reference and cannot replace personalised professional medical advice from a doctor. You are welcome to discuss any points during your consultation with our doctors.


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