It is known that sunscreen protects against skin cancer and a recent study published in the Annals of Internal Medicine show that sunscreen can also protect against signs of aging, such as wrinkles. Participants were randomized to either the treatment group who were told to apply sunscreen daily each morning and after bathing or excessive sweating or to the control group who were advised to use the sunscreen at their discretion. Researchers took impressions of the backs of participants’ hands at the beginning of the study and 4.5 years later. Trained blinded assessors analyzed microscopic changes in the hand impressions. Those in the daily use group were less likely to have increased aging than those in the control group. Although sunscreen has long been believed to reduce the signs of aging, this is the first comprehensive study to prove its usefulness against wrinkles (1).
Watch for new labeling on sunscreens as advised by the Food and Drug Administration (FDA). The first change is the use of the term “broad spectrum protection” which means the sunscreens have been proven to protect against UVA and UVB rays. The term waterproof cannot be used, only water-resistant and must state a duration of time indicating when the product will become ineffective. In addition, products with SPF lower than 15 cannot claim to protect against skin cancer. Although most products have made the necessary labeling changes, companies have through the end of the year to meet these label requirements (2).
A few key points in recommending a sunscreen this summer:
· The product should be at least SPF 30 and “broad spectrum.”
· Avoid sunscreen sprays altogether. They can be toxic if inhaled and often do not supply enough sunscreen onto the skin.
· Check the expiration date, sunscreen has a shelf life and effectiveness can deteriorate with time.
· Nanoparticles make the sunscreen transparent but efficacy and safety trials are lacking – until more research has been conducted these products should not be recommend.
1. Sunscreen and Prevention of Skin Aging. Annals of Internal Medicine. 2013 Jun;158(11):I-28.
2. Rabin, Roni Caryn. The New Rules for Sunscreen. http://well.blogs.nytimes.com/2013/05/27/the-new-rules-for-sunscreen/. Accessed June 6, 2013.
Posted by: Katie Yomen, PharmD Candidate 2014