I still walk on the beach near my home every day, even in summer. But no matter how hot it is, the only part of me that is exposed to the sun might be my fingernails. And usually not those. Bikini-clad teens roll their eyes at me like "What's the point?" From under the 6-inch brim of my sun hat, I try to beam back, "You have no idea what that tan is going to cost you."