Vitamin A: History, Current Uses, and Controversies
Vitamin A is required for the proper functioning of many important metabolic and physiologic
activities, including vision, gene transcription, the immune system and skin cell
differentiation. Both excessive and deficient levels of vitamin A lead to poor functioning of
many human systems. The biologically active form, retinoic acid, binds to nuclear receptors
that facilitate transcription that ultimately leads to it’s physiological effects. Retinoids are
derivatives of vitamin A that are medications used to treat acne vulgaris, psoriasis,
ichthyosis (and other disorders of keratinization), skin cancer prevention as well as several
bone marrow derived neoplasias. Systemic retinoids are teratogenic and have to be
prescribed with caution and close oversight. Other potential adverse events are controversial.
These include the relationship of retinoid derivatives in sunscreens, their effects on
bone mineral density, depression and suicidal ideation and inflammatory bowel disease.
These controversies will be discussed in detail.
Semin Cutan Med Surg 31:11-16 © 2012 Published by Elsevier Inc.