Vitamin D from Ultraviolet-B Exposure or Oral Intake in Relation to Cancer Incidence and Mortality.

Purpose Of Review: This review summarizes the understanding of vitamin D's role in reducing risk of cancer incidence and mortality.

Recent Findings: Recent randomized clinical trials and observational studies of participants who took part in vitamin D supplementation studies provide increasing evidence that concentrations of serum 25-hydroxyvitamin D [25(OH)D] up to ~ 60 ng/ml are inversely correlated with all cancer and some specific cancers' incidence and death, with a stronger effect on survival and death than on incidence. Mechanisms linking vitamin D to effects on cellular proliferation, anti-angiogenesis, and anti-metastasis continue to be found. Vitamin D reduces cancer risk causally. Maintaining 25(OH)D in the range of 40-60 ng/ml reduces the risk of many cancers. Raising 25(OH)D concentrations after diagnosis to that range increases survival rates and could significantly reduce the global burden of cancer incidence and death.