Yes, hair does age in two ways.
When you have long hair, the hair on your midlengths and ends can be anything from 5 to 50 years old, depending on how often, or if ever the hair has been cut. These end would have been exposed to our harsh environment for a long period of time, which explains why hair that hasn’t been coloured, is always lighter on the ends. The diameter of the ends can also be thinner than at the roots, due to the hair shaft splitting.
The other kind of aged hair that you get is that of an older person. Hair loses pigment, and gets thinner as the body slows down as we age.
There are a lot of products on the market for aged hair. Matrix has a range call Age Rejuvenate, L’Oréal Professional has Age Densi Force. These products give the hair the nutrients and care it needs, putting back the vitality, shine and bounce that it once had.