PSU Scientists Determine Why We Tan
Now that summer’s kicked into high gear, your skin is probably darker than normal, maybe even just an incidental tan. Hopefully it’s less than certain Mid-Atlantic youth of Italian extraction. Regardless, researchers at Penn State have actually come up with a new theory as to why our skin tans in the first place.
A study in the Department of Anthropology has found new reasons for the darkening of human skin pigments. This all goes back to evolution. In mid-to-northern latitudes where we live, the amount of ultraviolet B radiation that come in contact with our skin varies dramatically between seasons. UVB rays produce Vitamin D, and tanning is a natural mechanism for avoiding a deficiency of the nutrient. In fact, the researchers even found a connection between a Vitamin D shortage and the dark shade of skin pigments in those lacking. While UVB can also harm folate, needed for cell growth, when radiation levels drop, however, this allows for more production of Vitamin D and protects the folate.
This goes against previous theories, which, according to Penn State anthropology professor Nina Jablonski, “focused on the protective effects of melanin against sunburn, skin cancer, and overproduction of vitamin D.”
So I suppose the Jersey Shore hooligans are not off the hook when it comes to skin cancer. Though they certainly were always on it for every other kind. They can give a nod to Dear Old State next time they go for a nice bronzing, and so can you.
Read the full report here.