Protectores Solares

Current sunscreen controversies: a critical review
Mark E. Burnett & Steven Q. Wang
Dermatology Service, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
Key words:
sunscreen; skincancer; vitamin D;
oxybenzone; retinyl palmitate;
nanoparticles
Correspondence:
Steven Q. Wang, Dermatology Service, Memorial
Sloan-Kettering Cancer Center, 160 E 53rd St., New
York, NY 10022, USA.
e-mail:wangs@mskcc.org
Accepted for publication:
29 September 2010
Conflicts of interest:
None declared.
Summary
Background/purpose: Sunscreens are believed to be a valuable tool in providingphotoprotection against the detrimental effects of UV radiation, a known carcinogen.
However, a number of controversies have developed regarding their safety and efficacy. This
review summarizes the relevantstudies surrounding these controversies.
Methods: Evidence of the prevention of skin cancer, an oft-cited reason for sunscreen use, was
examined as it pertains to squamous cell carcinoma, basal cellcarcinoma and melanoma.We
also reviewed studies examining the effects of sunscreen on the synthesis of vitamin D, an
essential nutrient whose role in health and disease continues to grow. Lastly, weanalyzed
studies surrounding the safety and toxicity of oxybenzone, retinyl palmitate and
nanoparticles of zinc oxide (ZnO) and titanium dioxide (TiO2).
Results: The overwhelming majority of available data isdrawn from studies conducted using
antiquated sunscreen formulations. Nonetheless, our research revealed that topical use
of sunscreen protects against squamous cell carcinoma, does not cause vitaminD deficiency/
insufficiency in practice and has not been demonstrated to adversely affect the health
of humans.
Conclusion: Given the established benefits of UV protection, the use of sunscreensremains an
important part of an overall photoprotective strategy. Future sunscreens with improved
formulation should ideally offer superior protection. With increased usage of sunscreen by
the public,...