Does Systematic Use of Small Doses of Vitamin D Have Anti-Inflammatory Effects and Effectively Correct Deficiency Among Healthy Adults?

BACKGROUND: Calcitriol, beyond its well-established role in calcium and phosphate homeostasis, contributes to immunological processes. No known vitamin D dosage regimen effectively corrects the deficiency while accounting for immunoregulatory effects. Therefore, the purpose of this assessment was to determine whether regular administration of low doses of vitamin D might correct deficiency and have immunoregulatory effects. METHODS: A total of 35 healthy volunteers were asked to supplement with vitamin D daily at a dosage of 500 or 1000 IU, depending on the degree of deficiency, for 12 months. At the beginning of the study and after the end of the supplementation period, concentrations of 25(OH)D; PTH; total calcium; inorganic phosphorus; and the inflammatory cytokines IL-17, IL-10, TGF-β, and IFN-γ were determined in all participants. RESULTS: Correction of vitamin D deficiency was achieved with accompanying decreases in PTH and pro-inflammatory cytokine concentrations, while the concentration of anti-inflammatory cytokines remained stable. CONCLUSIONS: Therefore, regular vitamin D supplementation, even in small doses, effectively corrected the deficiency and had immunomodulatory effects.