From SPF to skin color, sunscreen’s effectiveness is complicated
Summary
This episode explores the science and regulation of sunscreen, highlighting the FDA's approval of bemotrizanol, the first new active ingredient in the U.S. in 25 years. Reporter Justine Paradis discusses why SPF ratings are often misleading and reviews the Nambour trial, the primary evidence linking sunscreen to reduced skin cancer risk. The segment also examines whether blanket public health advice to wear sunscreen applies to all skin tones, noting that melanin provides significant natural protection and that guidelines are evolving to be more specific.
Topics discussed
Introduction: Summer's last hurrah and sunscreen spotlight
Sunscreen as a complex, high-tech product
History of sunscreen from Red Vet Pet to Coppertone
FDA approval of new ingredient Bemotrizanol
Why the US lags behind in sunscreen innovation
The imperfections and inconsistencies of SPF testing
The Nambour Trial: Evidence for cancer prevention
Sunscreen efficacy and risks for people of color
Debating blanket vs. targeted public health advice
Conclusion: Sunscreen as the last line of defense
Credits and production team
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