shootingstar - I have the same problem with people in my parent's age bracket. My parents are in their mid-late 60's and yet they are active and they look very good for their age. I often forget that they are the age they are.

For example, this is my immediate family:

Does my father look to be 66? My mom 67? My brother (lower right) 39?

This is my frame of reference and it throws my judgement off!