I think people can look significantly older than their age - and I believe MN is likely to agree to that - and I also think people can look significantly younger than their age.
For some reason, people take it very personally when you talk about the latter and are very insistent that it is not possible. It is as if they must bring a person down a peg or two.
It shouldn't matter either way. Funnily enough, I am writing a fantasy book where the MC is early middle-aged. I have already nearly decreased her age once to be late 30s and had to really ask myself why. My thought process about what age meant was a little depressing.