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Updated: May 28, 2026
12:37
Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Factors influencing sunless tanning with dihydroxyacetone
1Wellman Laboratories of Photomedicine, Department of Dermatology, Massachusetts General Hospital, WEL-224, Harvard Medical School, 50 Blossom Street, Boston, MA 02114, USA.
The British Journal of Dermatology
|August 23, 2003
Summary
Sunless tanning reactions depend on hydration, pH, and amino acids. Optimizing these factors may enhance pigment and photoprotection from dihydroxyacetone (DHA) sunless tanners.
Area of Science:
- Dermatology
- Cosmetic Science
- Biochemistry
Background:
- Sunless tanning products utilize dihydroxyacetone (DHA) to create temporary pigmentation through reactions with stratum corneum amino acids.
- These preparations have been popular for over 50 years, mimicking a natural tan without UV exposure.
Purpose of the Study:
- To investigate factors influencing dihydroxyacetone (DHA) reactions with amino acids in the stratum corneum.
- The primary goal is to enhance DHA-induced pigmentation for improved photoprotection.
Main Methods:
- Assessed the impact of hydration and oxygen on DHA-induced pigment development in vivo and ex vitro.
- Utilized diffuse reflectance and fluorescence emission spectroscopy to quantify pigment formation.
- Studied the reaction kinetics between DHA and nine amino acids across different pH levels (5 and 7).
Main Results:
- Pigmentation was inhibited by occlusion but resumed post-occlusion, indicating DHA persistence.
- High hydration levels and absence of oxygen influenced coloration; pigmentation correlated with humidity up to 75% but decreased thereafter.
- Lysine, glycine, and histidine showed the fastest reactions with DHA, particularly at pH 7. Reaction products absorbed light up to 340 nm.
Conclusions:
- Stratum corneum hydration, pH, and specific amino acid availability are key determinants of DHA-induced pigmentation.
- Manipulating these factors presents an opportunity to develop sunless tanning products with enhanced photoprotective qualities.
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