The retinoids are a class of chemical compounds that are natural derivatives of vitamin A or are chemically related to it. Synthetic retinoids are used in medicine where they regulate skin health, immunity and bone disorders.
Retinoids have many important functions throughout the body, including roles in vision,[1] regulation of skin proliferation and differentiation, growth of bone tissue, immune function,[2] and male fertility.[3]
The biology of retinoids is complex and their use in medicine has well-known benefits in diseases like acute promyelocytic leukemia (APL) or acne. On the other hand, retinoids are known to have many harmful effects on metabolism[4] and cancer.[5]
^Goodman GE, Thornquist MD, Balmes J, Cullen MR, Meyskens FL, Omenn GS, et al. (December 2004). "The Beta-Carotene and Retinol Efficacy Trial: incidence of lung cancer and cardiovascular disease mortality during 6-year follow-up after stopping beta-carotene and retinol supplements". Journal of the National Cancer Institute. 96 (23): 1743–1750. doi:10.1093/jnci/djh320. PMID15572756.