the real reason for this is because there is little/no melanin cells in your palms or soles - you could stick them in the sun all day long, but they would never tan! melanin is the substance in your skin that turns brown when it is exposed to sunlight and protects you (to some degree) from the harmful rays in the sun. people from asia, africa and the carribean have much higher levels of melanin in their skin as they live in very sunny/hot areas and are therefore darker in colour to protect their skin from harmful rays, too. that's why we pale people burn in a little warm weather and have higher rates of skin cancer. you should always be careful and cover up in the sun (with clothes and sunscreen) - fake tan is always preferable to frying yourself outside. i'm only 32 and have olive skin which tans easily, but i had my first precancerous mole removed in december last year.