The discovery that sunlight can cure rickets was first scientifically confirmed in 1919. Shortly thereafter, in 1924, it was found that inactive lipids in the diet and skin are converted into antirachitic substances under the influence of UV light. Vitamin D (Vit D), also known as the "sunshine vitamin,"
was first identified in 1931. In recent decades, it has regained the focus of interest among the broader scientific community and dermatologists.
Specifically, certain dermatoses have been associated with low Vit D levels, leading to its supplementation in patients. On the other hand, some
dermatoses worsen with sun exposure, necessitating strict avoidance of sunlight and the therapeutic use of Vit D preparations.We are witnessing a
growing number of cases of melanoma and non-melanoma skin cancers, with excessive sun exposure being the primary etiological factor in most
cases. This paper provides a literature review on the historical discovery of Vit D and presents findings from studies examining Vit D levels not only in
various dermatoses but also in other diseases. The number of studies, as well as the spectrum of diseases in which the role of Vit D is being
investigated, continues to increase.