Beachgoers are familiar with the experience of spending hours in the sun, going home, and noticing only hours later that their skin has changed color.
A new Tel Aviv University study uncovers the science behind the mystery of why the body’s tanning process does not occur immediately after sun exposure, but only after a few hours or even days.
The research findings reveal the mechanism behind this phenomenon, according to which the body’s initial response is to prioritize repairing DNA damage in the skin cells, which inhibits the mechanism responsible for skin pigmentation, commonly known as tanning.
The study, published in the Nature Group’s Journal of Investigative Dermatology, was led by doctoral student Nadav Elkoshi and Prof. Carmit Levy of the Department of Human Molecular Genetics and Biochemistry at Tel Aviv University’s Faculty of Medicine, and in collaboration with a number of other researchers from Tel Aviv University, Wolfson Medical Center, the Weizmann Institute of Science, the University of California, and Paris-Saclay University.
We have two mechanisms designed to protect the skin from exposure to dangerous UV radiation. The first mechanism repairs the DNA in the skin cells damaged by the radiation, while the second mechanism involves increased production of melanin, which darkens the skin in order to protect it from future exposure to radiation. In our study, we discovered why the tanning phenomenon