Sunscreens in the United States: current status and future outlook

Abstract

Incidence rates of nonmelanoma skin cancer and melanoma has been on the rise in the United States for the past 20 years. UV radiation (UVR) exposure remains the most preventable environmental risk factor for these cancers. Aside from sun avoidance, sunscreens remain our best protection. UVR directly damages DNA and cause indirect cellular damage through the creation of reactive oxygen species, the sum of which leads to cutaneous immunosuppression and a tumorigenic milieu. The current generation of sunscreens protect from UVR through two main mechanisms: absorption and deflection. In the US, new Food and Drug Association rules require sunscreen manufacturers to evaluate their products not only on sun protection factor but also on broad spectrum UVA protection by the end of 2013. New labeling requirements will also be instituted. The American Academy of Dermatology and the American Academy of Pediatrics have provided specific recommendations for proper sun protection and sunscreen usage. Plant polyphenols such as those isolated from green tea, pomegranate, and grape seed remain an interesting avenue of research as additives to sunscreens or stand-alone products that appear to modulate the immunosuppressive effects of UVR on the skin. Additionally, although UVR induces endogenous cutaneous production of vitamin D, its damaging effects overshadow this positive benefit, especially in light of the ease of achieving recommended amounts of vitamin D through diet and supplementation.