Vitamin D: Implications for ocular disease and therapeutic potential

•Vitamin D deficiency is associated with development of various ocular pathologies.•Genetic variations in vitamin D pathway genes are associated with disease risk.•Ocular cells express vitamin D-related genes and can activate vitamin D.•Vitamin D treatment is protective in animal models of ocular disease.•In vitro studies suggest that vitamin D dampens inflammatory events in the eye.

Vitamin D is a multifunctional hormone that is now known to play a significant role in a variety of biological functions in addition to its traditional role in regulating calcium homeostasis. There are a large number of studies demonstrating that adequate vitamin D levels are important in maintaining health and show that vitamin D is able to be utilized at local tissue sites. In the eye, we have increasing evidence of the association between disease and vitamin D. In this narrative review, we summarize recent findings on vitamin D and its relationship to various ocular pathologies and the therapeutic potential for some of these, as well as examine the basic science studies that demonstrate that vitamin D is biologically relevant in the eye.