Vitamin D and psoriasis: an update for dermatologists and nutritionists.

Psoriasis is a common chronic immune-mediated inflammatory skin disease, now considered a systemic inflammatory process with several comorbidities. The skin produces vitamin D by the action of ultraviolet light. Vitamin D performs various immunomodulatory, anti-inflammatory, antioxidant and anti-fibrotic actions. The immunomodulatory effects of vitamin D offer opportunities to improve the treatment of several autoimmune diseases, such as psoriasis. In the literature, several significant associations are reported between low levels of vitamin D and psoriasis. Today, topical vitamin D represents an important therapeutic option due to its action on the proliferation and maturation of keratinocytes. The situation is different regarding the oral intake and integration of vitamin D in psoriasis patients. The use of vitamin D supplementation as an adjunctive treatment option in these patients is still discussed. This work aims to analyze the association between psoriasis and vitamin D levels according to dermatologists and nutritionists.