When we speak about boosting immune system, in most cases, we mean improved immune system against common infections. Such as: Influenza, COVID 19, common cold and other infections.
The most popular belief to boost immunity is taking Vitamin C, But, most evidence based way to boost immunity is vaccination.
So, first and important rule, Stay up-to-date on recommended vaccines.
Second: obesity has been correlated with a higher occurrence of chronic diseases.
Research findings indicate that obesity increases infectious diseases risk.
Even, COVID-19 severity is related to BMI ≥ 28.
Obtain or maintain Healthy weight is important way to improve immunity.
Third: Although it is well-known that exercise is a very active booster of immunity , whereas stress strongly alters the immune response.
Regular moderate intensity exercise is beneficial.
Improvements in immunity due to regular exercise of moderate intensity may be due to reductions in inflammation, maintenance of thymic mass, immune cells, enhanced immunosurveillance,
enhanced recirculation of immunoglobulins, anti-inflammatory cytokines, neutrophils, NK cells and lymphocytes. all of which play critical roles in immune defense activity and metabolic health.
Amelioration of psychological stress, which can suppress immune system activity.
Fourth:
Several nutraceuticals have been reported to have a significant impact on enhancing the immune system and aid in the treatment and/or protection of viral infections, particularly influenza-like diseases.
“Improving the body’s immune system” is the top reason for consuming nutritional supplements.
The “immune boosters” market includes vitamins, minerals, antioxidants, probiotics, and “functional foods”
US National Health and Nutrition Examination Survey showed that over 50% of the US population reported the use of supplements.
Studies showed that after influenza vaccination, the supplementation of vitamins A and D raised the humoral immunity of pediatric patients . In patients with torque teno virus (TTV), dietary supplementation with high levels of zinc resulted in improved immunity.
Vitamin D. can modulate the innate and adaptive immune responses. Deficiency in vitamin D is associated with increased autoimmunity as well as an increased susceptibility to infection.
vitamin D has important roles in addition to its classic effects on calcium and bone homeostasis. As the vitamin D receptor is expressed on immune cells (B cells, T cells and antigen presenting cells).
Vitamin D can modulate the innate and adaptive immune responses.
Vitamin C takes part in the development and functionality of various immune cells and the production of antibodies. Vitamin C enhances the function of epithelial barrier against pathogens.
It could accumulate in neutrophils to promote chemotaxis phagocytosis and with subsequent microbial killing.
It is also required for apoptosis and neutrophil clearance from the infection sites, which resulted in a reduction of necrosis and possible tissue damage.
In B and T lymphocytes, vitamin C might promote the cellular differentiation and proliferation due to its gene-regulating activities. Therefore, vitamin C supplementation seems to be able to prevent and treat the respiratory and systemic infections.
Vitamin E, also has functions in regulating the immune response. But, numerous studies showed that supplementation with vitamin E could have harmful effects on the immune system, especially in cancer and cardiovascular diseases.
By NIAID – Influenza Virus, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=39933111
By Thomas Splettstoesser (www.scistyle.com) – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=92093641
