The importance of maintaining vitamin D levels for the immune system. Research, Society and Development, [S. l.], v. 10, n. 12, p. e284101220453, 2021. DOI: 10.33448/rsd-v10i12.20453. Disponível em: https://rsdjournal.org/rsd/article/view/20453. Acesso em: 5 dec. 2025.