Immune Competence and Minimizing Susceptibility to COVID-19 and Other Immune System Threats.

Exposure to viruses, bacteria, and other pathogens is unavoidable. Yet, the mere presence of these threats is not enough to automatically predispose to illness. The susceptibility of an individual to viral or bacterial infections is dependent upon immune competence. Many factors can interfere with the functioning of the immune system. Epigenetic alterations in the form of lifestyle or environmental factors can lead to impaired immunity. For example, exposure to air pollution can increase the risk of complications and mortality from COVID-19. Obesity can also exacerbate the damaging effects of air pollution on the lungs and may enhance the association between air pollution and increased COVID-19 severity. Poor sleep is another factor leading to impaired immunity, likely due to the coinciding melatonin depletion. Melatonin has been found to have antiviral and immune-enhancing effects, and it has been proposed that this hormone may be beneficial in COVID-19 patients. Zinc and vitamins D and C have also been well studied for their ability to shorten the duration of upper respiratory infections, and vitamin D has been found to reduce mortality in COVID-19 patients. Cannabidiol can both directly and indirectly improve immunity by enhancing natural killer cell activity, reducing inflammation, and relieving stress. Other dietary supplements backed by solid scientific evidence to show they act as immune enhancers are astragalus, a yeast fermentate (EpiCor®), olive leaf extract, berberine, N-acetyl cysteine, and garlic.