Vitamin D or Flu Vaccine-Benefits over Adverse Effects

Available data suggests that calcitriol has a role in controlling pulmonary inflammation by inducing the production of natural broad-spectrum antimicrobial peptides, the so-called cathelicidin. Randomized clinical studies reported that vitamin D supplements in a daily-wise manner caused a significant risk reduction in acute respiratory tract viral infections and participants who were given vitamin D supplementations were half less infected with flu than those who were not given the vitamin. Hence, vitamin D3 supplementation may be advantageous when compared with flu vaccine especially when we put in consideration morbidities and complications caused by this vaccine as well as the conditions in which influenza vaccine may be contraindicated like in patients who receive cancer immunotherapies targeting the programmed death-ligand 1 (PD-L1) or its receptor, programmed cell death protein 1 (PD-1).