The current evidence supports the benefits of vitamin D interventions in patients hospitalized with COVID-19 due to the protective effect provided by vitamin D against ICU admission and mortality. A meta-analysis per se does not allow us to state whether the results are truly positive or false-positive. In addition, the inclusion of studies with large effect sizes and significant heterogeneity separates us from the truth. For this reason, a TSA is mandatory to verify the reliability of meta-analysis results [ 92]. In conclusion, the positive results highlighted again and now validated by TSAs suggest that an indisputable association between vitamin D supplementation and the protective effect on ICU admission can be considered definitive evidence. On the contrary, further studies are needed to assess the utilization of vitamin D regarding the risk of death in patients hospitalized with COVID-19.