The Tokyo Institute of Gerontology, located at the Tokyo Metropolitan Geriontologic Hospital, in cooperation with the Tokyo University of Agriculture and Technology, reported on the mechanism by which epidermis is withering and deposits melanin. Based on experiments on man and a hairless mouse model (SMP30/GNL KO), the amount of residual vitamin C in the skin is crucial for the onset of these effects.

Tokyo Institute of Gerontology press release, April 24, 2012