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Updated: Jun 19, 2026
12:37
Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Are dark-skinned people really protected from ultraviolet radiation?
A L Young1, S Levy, M Nighland
1Department of Dermatology, Columbia University Medical Center, New York, NY 10032, USA.
Clinical and Experimental Dermatology
|October 31, 2009
Summary
Dark-skinned individuals exhibit solar elastosis, a sign of premature skin aging from UVR, indicating melanin offers only partial protection. This study quanties elastosis in diverse skin tones.
Area of Science:
- Dermatology
- Photobiology
- Histopathology
Background:
- Premature skin aging, or photoaging, is caused by ultraviolet radiation (UVR).
- Solar elastosis, a histopathological marker of photoaging, manifests as changes in the dermis.
- Skin pigmentation offers a degree of protection against UVR damage.
Purpose of the Study:
- To investigate the prevalence and severity of solar elastosis in individuals with dark skin.
- To compare photoaging indicators between dark-skinned and light-skinned populations.
Main Methods:
- Histopathological examination of facial skin biopsies from 147 dark-skinned and 140 light-skinned individuals.
- Dermatopathologists, blinded to patient data, graded solar elastosis on a five-point scale.
Main Results:
- High-grade solar elastosis was observed in 80% of light-skinned individuals and 34% of dark-skinned individuals.
- Within the dark-skinned group, 47.5% of Hispanic and 10.2% of African American subjects showed high-grade solar elastosis.
- These findings highlight variations in UVR-induced skin aging across different ethnicities.
Conclusions:
- Dark-skinned individuals are not fully protected from the aging effects of UVR.
- Solar elastosis occurs in dark skin, underscoring the need for sun protection regardless of skin tone.
- Further research can explore genetic and environmental factors influencing photoaging in diverse populations.
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