Have you ever wondered why it takes a while for your skin to tan after spending some time under the sun? It’s especially annoying when you spend time at the beach and when you leave everything is fine, but a few hours later to you start to feel the effects of sunburn. Well, researchers from Tel Aviv University say they may have found the reason why this happens.
Specifically, a new study uncovered 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.
Will you offer us a hand? Every gift, regardless of size, fuels our future.
Your critical contribution enables us to maintain our independence from shareholders or wealthy owners, allowing us to keep up reporting without bias. It means we can continue to make Jewish Business News available to everyone.
You can support us for as little as $1 via PayPal at [email protected].
Thank you.
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.
Nadav Elkoshi explains: “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 does not occur immediately when the body is exposed to the sun, but only following a delay. It turns out that the mechanism that repairs our DNA takes precedence over all other systems in the cell, temporarily inhibiting the pigmentation mechanism. Only after the cells repair the genetic information to the best of their ability do they begin to produce the increased melanin.”
To test their hypothesis, the Tel Aviv University researchers activated the DNA repair mechanism in both animal models and human skin tissues. In both, a tan developed even without any exposure to UV radiation, substantiating their findings.
Prof. Carmit Levy went on to explain that genetic information must be protected from mutations, and so this repair mechanism takes precedence inside the cell during exposure to ultraviolet radiation from the sun. The DNA repair mechanism essentially tells all the other mechanisms in the cell, “Stop everything, and let me work in peace.”
“One system effectively paralyzes the other,” said Carmit, “until the DNA correction reaches its peak, which occurs a few hours after the UV exposure. Only then does the pigment production mechanism get to work. In our previous research, we showed that a protein called MITF, which is activated during exposure, is responsible for regulating these two mechanisms. “
But whatever the reason for all of this, whether the tan or burn happens immediately or not, remember a tan skin is a damaged skin. Sunburns can cause skin cancer down the road, and so can even suntans acquired gradually.
The best thing to do is use plenty of sunblock and avoid direct sunlight in the summer as much as possible, especially if you have a light complexion.
