The COVID-19 pandemic has severe short-term consequences with high mortality in high risk groups, and can have long-term consequences with possible collapse of the health care system and an economic recession. Studies have shown that vitamin D can reduce the risk of viral infections in many ways, also the risk of infection with enveloped viruses, such as SARS-CoV-2. In the period of viral infections and especially in the COVID-19 pandemic, it is important, mostly in individuals at high risk of vitamin D deficiency and at high risk of COVID-19 morbidity, to maintain adequate vitamin D body levels.