Nutritional importance of vitamin D in the prevention of COVID-19: a systematic review. Research, Society and Development, [S. l.], v. 10, n. 15, p. e102101522404, 2021. DOI: 10.33448/rsd-v10i15.22404. Disponível em: https://rsdjournal.org/rsd/article/view/22404. Acesso em: 5 dec. 2025.