Can vitamin c boost immune system
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Can Vitamin C Boost the Immune System?
Vitamin C and Immune Function
Vitamin C, also known as ascorbic acid, is a crucial micronutrient for humans, playing multiple roles due to its ability to donate electrons. It acts as a potent antioxidant and a cofactor for various biosynthetic and gene regulatory enzymes. Vitamin C supports 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 stress1 7.
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 essential for microbial killing. It also aids in the apoptosis and clearance of spent neutrophils from infection sites by macrophages, reducing potential tissue damage1 7. Additionally, vitamin C has been shown to enhance the differentiation and proliferation of B- and T-cells, likely due to its gene-regulating effects1 5.
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 crucial for optimal immune function1 7.
Supplementation and Immune Response
While a balanced diet that meets the daily intake of vitamin C positively affects the immune system, the impact of high-dose vitamin C supplements on boosting immunity is less clear. Current data do not support the theory that oral vitamin C supplements significantly decrease the risk of respiratory infections in a well-nourished general population. However, supplementation may be beneficial for specific subgroups, such as athletes, the military, and individuals with low plasma vitamin C concentrations2.
Vitamin C in Special Populations
In populations at high risk of infection, such as the elderly, obese, and diabetics, vitamin C supplementation can modulate inflammation and potentially enhance the immune response to infections. This is particularly important in low- and middle-income countries and among subpopulations in industrialized countries where nutrient intake may be insufficient2 7.
Clinical Applications and Research
Vitamin C has been studied for its potential to prevent and treat respiratory and systemic infections. Prophylactic prevention of infections requires dietary intakes that provide at least adequate plasma levels (100-200 mg/day), while treatment of established infections may require higher doses to meet increased inflammatory and metabolic demands1 7. Recent studies have also explored the role of vitamin C in critical illness conditions, such as COVID-19, where it has been hypothesized to improve clinical outcomes by attenuating excessive immune responses2 10.
Conclusion
Vitamin C plays a vital role in supporting the immune system through various mechanisms, including enhancing the function of phagocytic cells, promoting the proliferation of lymphocytes, and maintaining the epithelial barrier. While adequate dietary intake of vitamin C is essential for immune health, the benefits of high-dose supplementation are more evident in specific subgroups and high-risk populations. Further research is needed to fully understand the potential of vitamin C in boosting immunity and its application in clinical settings.
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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 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.
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Low vitamin C levels can negatively impact immune cell function, cell metabolism, and epigenetics, potentially affecting inflammation and cancer.
Highly CitedVitamin 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 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.
A 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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