Vitamin c boost immune system
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The Role of Vitamin C in Boosting the Immune System
Vitamin C and Immune Function
Vitamin C, also known as ascorbic acid, is a crucial micronutrient with multiple roles in the human body, particularly in the immune system. It acts as a potent antioxidant and a cofactor for various biosynthetic and gene regulatory enzymes. Vitamin C supports the immune defense by enhancing the functions of both the innate and adaptive immune systems. It helps maintain the epithelial barrier against pathogens and promotes the scavenging of oxidants, protecting against environmental oxidative stress 17.
Cellular Functions and Immune Defense
Vitamin C accumulates in phagocytic cells such as neutrophils, enhancing their chemotaxis, phagocytosis, and the generation of reactive oxygen species, which are crucial for microbial killing. It also plays a role in apoptosis and the clearance of spent neutrophils from infection sites by macrophages, reducing tissue damage 17. Additionally, vitamin C is essential for the differentiation and proliferation of B- and T-cells, which are vital for adaptive immunity 18.
Impact of Vitamin C Deficiency
A deficiency in vitamin C can lead to impaired immunity and increased susceptibility to infections. Infections, in turn, deplete vitamin C levels due to enhanced inflammation and metabolic demands. Therefore, maintaining adequate vitamin C levels is essential for optimal immune function 17.
Vitamin C Supplementation and Immune Response
Supplementation with vitamin C has been shown to improve various components of the immune system, including antimicrobial and natural killer cell activities, lymphocyte proliferation, chemotaxis, and delayed-type hypersensitivity. These effects are particularly beneficial in populations with insufficient intake of vitamin C, such as the elderly and those in low- and middle-income countries 6. High doses of vitamin C are required to treat established infections due to increased inflammatory responses and metabolic demands 17.
Vitamin C in Special Populations
While a balanced diet that meets the daily intake of vitamin C positively affects the immune system, high-dose supplements do not significantly decrease the risk of respiratory infections in a well-nourished general population. However, supplementation may be justified in specific subgroups, such as athletes, military personnel, and individuals with low plasma vitamin C concentrations. In high-risk groups, such as the obese, diabetics, and the elderly, vitamin C supplementation can modulate inflammation and enhance immune response 2.
Vitamin C and Critical Illness
Recent studies have explored the potential of vitamin C in treating critical illnesses, including COVID-19. Vitamin C has been shown to increase antiviral cytokines, reduce viral yield, and attenuate excessive inflammatory responses, which can be beneficial in managing acute respiratory tract infections and improving clinical outcomes in COVID-19 patients 10.
Conclusion
Vitamin C plays a vital role in supporting the immune system through its antioxidant properties and its ability to enhance various cellular functions. While maintaining adequate vitamin C levels is crucial for overall immune health, high-dose supplementation may be beneficial in specific populations and critical illness conditions. Ensuring sufficient intake of vitamin C through diet or supplements can help bolster the immune system and reduce the risk and severity of infections.
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Most relevant research papers on this topic
Vitamin C and Immune Function
Vitamin C contributes to immune defense by supporting various cellular functions of both the innate and adaptive immune systems, enhancing microbial killing, and preventing and treating respiratory and systemic infections.
Very Rigorous Journal
Highly CitedThe Long History of Vitamin C: From Prevention of the Common Cold to Potential Aid in the Treatment of COVID-19
Vitamin C supplementation may be beneficial for certain groups at high risk of infection, but its effectiveness in reducing respiratory infections remains unclear.
Literature ReviewHighly CitedVitamin C and immune cell function in inflammation and cancer
Low vitamin C levels can negatively impact immune cell function, cell metabolism, and epigenetics, potentially affecting inflammation and cancer.
Highly CitedEffect of vitamin C supplements on cell-mediated immunity in old people.
Vitamin C supplements can enhance T lymphocyte proliferation and tuberculin skin hypersensitivity in elderly individuals, but do not significantly affect serum IgA, IgG, and IgM levels.
RCTHighly CitedVitamin C as A Possible Immunity Booster
Vitamin C may enhance immune system function by regulating white blood cell health and gene expression, potentially improving infection prevention and treatment.
Literature ReviewImmune-Enhancing Role of Vitamin C and Zinc and Effect on Clinical Conditions
Vitamin C and zinc supplementation improves immune function and reduces the risk, severity, and duration of infectious diseases, particularly in developing countries.
Highly CitedRole of Vitamin C in Immune Function of Human Body
Vitamin C plays a crucial role in immune system defense, supporting various cellular functions and reducing the risk of various cancers and eye diseases.
Vitamin C promotes maturation of T-cells.
Ascorbic acid plays a crucial role in T-cell maturation and enhances immune function through its role in lymphoid cell-intrinsic development and epigenetic mechanisms.
In Vitro StudyHighly CitedA mathematical model showing the potential of vitamin c to boost the innate immune response
Vitamin C can boost the innate immune response and potentially eradicate viral/bacterial infections and help combat diseases like renal failure, acute lung injury, liver damage, chronic granulomatous disease, and Chédiak-Higashi syndrome.
The Role of Vitamin C, Vitamin D, and Selenium in Immune System against COVID-19
Vitamin C, vitamin D, and selenium supplements can enhance the immune system's response to COVID-19 by improving physical barrier, preventing cytokine storms, and enhancing T cell maturation and antibody production.
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