It has been determined that vitamin D, together with elements of response to said vitamin located in the promoter region of several genes, serve as an important factor for the prevention of adverse results of covid-19, due to its regulatory functions in the renin system. angiotensin (SRA), innate and adaptive cellular immunity, physical barriers, among others. In the absence of a safe treatment of Covid-19, this study was carried out with the objective of making a comparison between the effect of a single high oral dose of cholecalciferol versus a standard dose in older adults infected by SARS-CoV2 at higher risk. worsening, proposing a rigorous protocol that meets the best standards of clinical research to provide a response with the highest level of evidence possible. Despite the fact that this research is very precise due to its methodology, there are factors that could generate biases, such as the fact that various subgroups were used, leading to possible misleading results. According to the results of this first randomized trial, high-dose vitamin D supplements can be an effective, well-tolerated, and readily accessible treatment for COVID-19.