The changes of hair lipid composition induced by UV irradiation on three ethnic hairs

  • Dr Jae Hong Ji, Department of Dermatology and Institute of Hair and Cosmetic Medicine, Yonsei University Wonju College of Medicine, Korea
  • Mr Youn-Duk Kim, Department of Dermatology and Institute of Hair and Cosmetic Medicine, Yonsei University Wonju College of Medicine, Korea
  • Mr Sung-Hae Kim, Department of Dermatology and Institute of Hair and Cosmetic Medicine, Yonsei University Wonju College of Medicine, Korea
  • Dr Won-Soo Lee, Department of Dermatology and Institute of Hair and Cosmetic Medicine, Yonsei University Wonju College of Medicine, Korea

Integral hair lipid plays a key role in the maintenance of hair integrity including hydrophobicity and stiffness. UV irradiation induce photochemical degradation of hair shaft.
The purpose of this study was to investigate lipid changes after UV irradiation in three ethnic hairs. We had irradiated hair shaft using UV irradiator. We evaluated the changes of hair lipid using HPTLC, weighing balance and LC-Mass.
The lipid composition of three normal ethnic hairs were similar, but Asian hair has higher amount of free fatty acid than other two ethnic hairs. Especially African hair has higher amount of squalene than others. After UV irradiation, 18-MEA level was decreased. These pattern was shown in all three ethnic hairs.
We thought from our results that UV irradiation caused hair weaken, so extractable lipid was extracted easily. Integral hair lipid has differences in amount and composition between races, and UV irradiation alters the integral hair lipid.