Climate. Cold, dry air is hard on the skin. In humid places like Houston there are forty year olds that you have to take a second look at to realize their age.
The other day I flipped on the TV and they were interviewing a woman trying out to be a Texan cheerleader. There seemed to be something not quite right about her but it wasn't readily apparent what it was. Finally I heard them say she was a forty years old.
And that is the reason I won't leave Houston. I enjoy being mistaken for my teenage daughter Dale.