Why are people's palms lighter than the rest of their skin?

Question

Same thing with the bottom of the feet. You can't really tell so much on white people, but the darker you get the more obvious it is. I thought it was the sun, but even naked the color is the same; unless you tan.

Answer 1

Because there are no color pigments there. Even if you laid your palm in the sun for a year, the color would still not change.

Answer 2

The palms and soles have thicker skin.  It has many more layers of dead skin so the sun would have to penetrate much further to tan and neither do receive as much sun.

Answer 3

Because the sun hits certain spots.  Bottom of feet and palms rarely see sunlight.  Were talking thousands of years here.