Vitamin C is an essential nutrient for humans and contributes to immune defence by bolstering the function of both the innate and adaptive immune system. It is also a powerful antioxidant that serves as a cofactor for gene regulatory enzymes.  

Deficiencies in vitamin C ultimately result in impaired immunity and a higher vulnerability to infection. Vitamin C cannot be endogenously synthesised by humans and thus, requires an external source (diet or supplementation) to be obtained. Additionally, vitamin C is a water soluble compound, meaning it has a poor ability to be retained by the body and requires regular consumption. 

It is for this reason that supplementation may serve to be a more reliable source of Vitamin C than diet alone. Population studies have indicated that Hypovitaminosis C (or vitamin C deficiency) is relatively common in western populations even with access to necessary dietary sources and is the 4th leading nutrient deficiency in the United States. This is postulated to be the result of poor dietary/lifestyle habits as well as inadequate supplementation in the face of oxidative stress, which can be induced by physical and psychological stress. 

Vitamin C also serves as a cofactor to many important processes, such as the absorption of Iron, the synthesis of catecholamine hormones (which are central to the cardiovascular systems response to infection), downregulates the production of histone (an inflammatory marker), and even the support of the synthesis of collagen for supporting healthy barrier integrity.

In fact, the skin has numerous essential functions, the primary of which being serving as a barrier against external stressors, including bacteria/pathogens. Vitamin C is stored in the epidermis and plays crucial protective functions in the skin such as accelerating wound healing and protecting against pro-oxidant damage. Vitamin C’s importance to the skin is also bolstered by the fact that most confronting symptoms of severe vitamin C deficiency (scurvy) are seen on the skin — pale/ash-y complexion, bleeding gums, bruising and impaired wound healing.             

Studies have also indicated that vitamin C supplementation daily is effective in mitigating the severity and duration of the common cold, as well as the incidence of the common cold if also exposed to physical stressors (i.e. intense exercise). In a study that observed the effect of vitamin C on patients with acute respiratory infections, vitamin C was able to return their plasma levels to normal and reduce the severity of the respiratory symptoms verified by chest X-rays results.[1]The studies on the relationship between immune function and vitamin C are rigorous and appear in a multitude of peer-reviewed journals.

Vitamin C has also been demonstrated to mitigate exercise induced muscle soreness and calcium loss. Creatine kinase is a biological marker indicative of muscle damage, and typically elevates most acutely after exercise or an increase in exercise intensity. It is also one of the key contributors to muscle soreness experienced by individuals after exercise. In a study that aimed to investigate if vitamin C supplementation before and after exercise could reduce muscle soreness, eighteen healthy men were randomly assigned to either a placebo or vitamin C. Vitamin C supplementation demonstrated potential in attenuating release of high levels of creatine kinase after intense exercise and significantly reduced exercise induced muscle soreness, in comparison to placebo.[2]

Zinc and Immunity
The significance of the essential trace element zinc for immune function has been known for several decades and is particularly important for the maintenance of immune cells in both the innate and adaptive immune system.

Zinc deficiency affects the production and efficiency of immune cells, resulting in decreased host defence and increased risk of inflammation. In a study that monitored the relationship between zinc and the common cold, it was concluded that in comparison with the placebo group, the zinc group had a shorter mean overall duration of cold (4.0 vs. 7.1 days), a shorter duration of cough (2.1 vs. 5.0 days) and less nasal discharge (3.0 vs. 4.5 days).  [3]

During chronic zinc deficiency, the production of pro-inflammatory molecules (or pro-oxidants) grows, increasing the likelihood of a large number of inflammatory diseases, like rheumatoid arthritis, which has significant ramifications for athletes and the general population due to its high burden. Zinc has not only been documented as having a protective benefit against the development of rheumatoid arthritis, but also in helping alleviate afflicted individuals. A study published in 2009 reported beneficial alleviation of symptoms after zinc supplementation, with respect to joint swelling, morning stiffness and difficulty walking, in patients with rheumatoid arthritis in comparison to placebo trials. 

While we are often told to exercise to stay healthy, highly active individuals are vulnerable to illness due to the increased physiological stress incurred by their body, as well as the depletion of resources and energy needed for muscle repair. In the maintenance of a healthy immune system, cycling Vitamin C and Zinc serves as the gold standard therapy to have in your arsenal to ensure exercise does not deplete the range of nutrients needed for the maintenance of other key physiological functions, particularly immunity.

The synergistic effects of these two star compounds ensure that you are supported through every stage of your training regimen, particularly by exerting a protective benefit onto your immune system, and also helping you bounce back from illness faster, ensuring that you can continue doing what you love with minimal disruptions.

PILLAR’s Immune Range is here to support your physical and mental wellbeing with clinically backed, and well-tolerated blends at every stage of your training regimen.

References:
[1] Bharara A., Grossman C., Grinnan D., Syed A.A., Fisher B.J., DeWilde C., Natarajan R., Fowler A.A. Intravenous vitamin C administered as adjunctive therapy for recurrent acute respiratory distress syndrome. Case Rep. Crit. Care. 2016;2016:8560871.

Fowler A.A., Kim C., Lepler L., Malhotra R., Debesa O., Natarajan R., Fisher B.J., Syed A., DeWilde C., Priday A., et al. Intravenous vitamin C as adjunctive therapy for enterovirus/rhinovirus induced acute respiratory distress syndrome. World J. Crit. Care Med. 2017;6:85–90

[2] Bryer SC, Goldfarb AH. Effect of high dose vitamin C supplementation on muscle soreness, damage, function, and oxidative stress to eccentric exercise. Int J Sport Nutr Exerc Metab. 2006 Jun;16(3):270-80 

[3] Prasad AS, Beck FWJ, Bao B, et al. Duration and severity of symptoms and levels of plasma interleukin-1 receptor antagonist, soluble tumor necrosis factor receptor, and adhesion molecules in patients with common cold treated with zinc acetate. J Inf Dis 2008; 197:795 – 802.