Presentation on theme: "Testimony to the FDA Hearing on Tanning Bed Classification Barbara A. Gilchrest, M.D. Practicing Dermatologist & Professor of Dermatology Boston University."— Presentation transcript:
Testimony to the FDA Hearing on Tanning Bed Classification Barbara A. Gilchrest, M.D. Practicing Dermatologist & Professor of Dermatology Boston University School of Medicine Boston, MA March 25, 2010
Drugs and devices are evaluated based on a risk: benefit analysis. Tanning beds pose a well documented risk of skin cancer, photoaging, and (less often) exacerbation of multiple skin diseases. The only claimed benefit, aside from cosmetic tanning, is vitamin D production.
Sunburn Skin Cancer Photoaging vs Vitamin D Photosynthesis The Pseudo-Controversy Tanning Melanoma is unquestionably among the types of skin cancer caused by UV exposure.
The Pseudo-Controversy Should the public maximize vitamin D levels through intentional UV exposure in order to prevent cancer, hypertension, diabetes, multiple sclerosis … ? Which is the lesser evil? Skin cancer and photoaging or cancer of the colon, breast, prostate, and other organs in combination with the other listed diseases?
What evidence supports the argument that “insufficient vitamin D” or its proxy – lack of UV exposure – causes these diseases? Some but far from all Some but far from all epidemiologic associations. epidemiologic associations. These associations may be These associations may be confounded by obesity and confounded by obesity and lifestyle. lifestyle. Very few intervention studies. Very few intervention studies. Most show no effect of Most show no effect of vitamin D supplementation, vitamin D supplementation, even for many years. even for many years. Reddy & Gilchrest. JID 130: , 2010.
The Pseudo-Controversy is Irrational Ample vitamin D can be obtained from diet, supplements, and incidental sun exposure. A supplement of 1000 IU/day is safe and “sufficient” by even generous criteria.
The Pseudo-Controversy is Irrational Cutaneous vit D photosynthesis is least efficient for population groups at highest risk of vit D deficiency Darkly pigmented individuals Darkly pigmented individuals The elderly The elderly The group most responsive to the “unprotected sun exposure” message is at lowest risk of vitamin D deficiency Healthy Caucasian teenagers and young adults – tanning Healthy Caucasian teenagers and young adults – tanning salon customers! salon customers!
UV Action Spectra in Human Skin Wolpowitz & Gilchrest. JAAD, Adapted from Matsuoka et al. J Clin Endocrinol Metab, 1987; de Gruijl. Eur J Cancer, 1999; and Parrish et al. Photochem Photobiol, 1982 Wavelength (nm) Relative Effectiveness
Dose-Response Relationships for UV Effects From: Gilchrest BA. Editorial / review in J. Steroid Biochem Mol Biol, J. Steroid Biochem Mol Biol, 2007.
Why is There a Pseudo-Controversy? The sun protection message is The sun protection message is old (and wimpy). old (and wimpy). People, especially teenagers, People, especially teenagers, want to sunbathe and tan. want to sunbathe and tan. Sunbathing and making one’s Sunbathing and making one’s own vitamin D have a back-to own vitamin D have a back-to nature holistic appeal. nature holistic appeal. The indoor tanning industry The indoor tanning industry knows it’s good for business. knows it’s good for business.
Roadside advertisement in Ontario. U.S. state legislatures are bombarded with selected epidemiologic studies that support a cancer prevention effect of high 25(OH)D levels.
Vitamin D Supplements Are Cheap! 1000 IU Tablets Cost/tablet CVS Pharmacy$.06 CVS Pharmacy$.06 Nature Made$.09 Nature Made$.09 Life Fitness$.07 Life Fitness$.07 CVS Pharmacy$.05 CVS Pharmacy$.05
However much vitamin D people need, they don’t need this!