Vitamin C contributes to immune defense by supporting various cellular functions of the instilled and adaptive immune system. Vitamin C supports barrier function against pathogens and promotes the activity of eliminating skin oxidants, protecting against environmental oxidative stress. In addition, it accumulates in phagocytics, such as neutrophils, and can increase chemotaxis, phagocytosis, generation of reactive oxygen species and, finally, microbial death. Now know the relationship of vitamin C and immunity.
Vitamin C and immunity
Vitamin C is an essential nutrient that cannot be synthesized by humans due to the loss of a key enzyme in the biosynthetic pathway. Severe vitamin C deficiency results in a potentially fatal disease, scurvy. This disease is characterized by weakening of collagen structures, resulting in poor wound healing and impaired immunity. Individuals with scurvy are highly susceptible to fatal infections such as pneumonia. In turn, infections can significantly affect vitamin C levels due to increased inflammation and metabolic requirements.
Overall, vitamin C seems to exert a multitude of beneficial effects on cellular functions, both of the ininate and adaptive immune systems. Although vitamin C is a potent antioxidant protecting the body against endogenous and exogenous oxidative challenges. Its cofactor action is likely to have a major impact, as numerous biosynthetic and gene-regulating enzymes play a key role in its immunomodulatory effects.
Vitamin C stimulates neutrophil migration to the site of infection, increases phagocytosis, oxidant generation and microbial death. At the same time, it protects host tissue from damage by increasing neutrophil apoptosis and macrophage clearance, and decreasing necrosis. Thus, it is evident that vitamin C is necessary for the immune system to assemble and maintain an adequate response against pathogens, avoiding excessive damage to the host. In addition, it seems to be able to prevent and treat respiratory and systemic infections by improving various immune cell functions.
Prophylactic prevention of infection requires the intake of vitamin C in the diet that provides at least adequate plasma levels, i.e. 100–200 mg/day. In contrast, treatment of established infections requires significantly higher doses (grams) of the vitamin to compensate for increased metabolic demand.
Vitamin C supplementation in oxidative stress
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Nutrition and immunity in times of covid-19
Article: Vitamin C and
immunity – Carr AC, Maggini S. Vitamin C and Immune Function. Nutrients
. 2017;9(11):1211. Published 2017 Nov 3. doi:10.3390/nu9111211