is speculated to reduce infection severity in COVID-19, but previous research has not found antioxidants supplementation to be effective in the prevention of other diseases. Shifting from the typical western diet to a Mediterranean diet or plant-based diet may improve COVID-19 health outcomes by reducing prevalence of comorbidities (i.e. obesity or hypertension), decreasing intake of pro-inflammatory foods, and increasing consumption of anti-inflammatory and antioxidant nutrients. Research While SI may be induced by multiple external factors, research suggests that a lack of control by tolerogenic dendritic cells and T-regulatory cells (Treg) is possibly the primary risk factor for the development of SI. In functioning immune responses, T-helper and T-cytotoxic cells are activated by presentation of antigens by antigen-presenting cells (APCs). Chief among these are dendritic cells (DCs). When a DC presents an antigen to a Treg cell, a signal is then sent to the nucleus of the DC, resulting in the production of Indoleamine 2,3- Dioxygenase (IDO). IDO inhibits T cell responses by depleting tryptophan and producing kynurenine, which is toxic to the cell. Individuals susceptible to developing chronic systemic inflammation appear to lack proper functioning of Treg cells and TDCs. In these individuals, a lack of control of inflammatory processes results in multiple chemical and food intolerances, autoimmune diseases. See also Appendicitis Bursitis Colitis Cystitis Dermatitis Phlebitis RSD/CRPS Rhinitis Tendonitis Tonsillitis Vasculitis Disease Systemic disease Adult-onset Still's disease References Inflammations