Recent studies support the hypothesis that high folic acid (FA) levels could be a positive factor in diminishing the severity of COVID-19. In , the authors found that pregnant women, which usually take FA, seemed to be less affected by the SARS-CoV-2 virus than for the A-H1N1 influenza variant. For this study, the researchers contrasted COVID-19 hospitalization data from the UK's National Institute of Health against A-H1N1 data from the Department of Public Health of California . The study in classified 162 COVID-19 patients by their intensity of symptoms and different clinical variables that may explain this difference, including folic acid concentration. Table shows their results and suggests that patients with higher concentrations of FA experienced milder symptoms. However, the molecular mechanisms by which FA could reduce the severity or prevent infection of the SARS-CoV-2 virus are still under debate. Moreover, there is a lack of research on how these mechanisms may interact with newer variants of this virus. The SARS-CoV-2 virus initiates cell infection after binding to the ACE2 receptor through the interaction with its Receptor Binding Domain (RBD). RBD is a structure that emerges from the virus' Spike as a result of the action of furin and it has been the target of various attempts to combat this pandemic . The hypothesis tested in this research is that some folate metabolites, acting through an unknown mechanism, reduce the severity of the SARS-CoV-2 infection. In order to gain insight into this mechanism, the 7,8-dihydrofolate (DHF) metabolite was chosen because this is the first metabolite to which FA is reduced after entering the bloodstream. This reduction is catalyzed by the DHF-Reductase enzyme, which is continuously regenerated by thymidylate synthase in the dihydrofolatetetrahydrofolate cycle .