How old is Superman?

[adrikito]

Like 40 years. I remember that in rebirth was mentioned that he had 38 years.

[stargazer01]

For Superman 40 is like 20, imo. He's not human.

[Jim Kelly]

But wouldn't Clark need to look older? Or is he Rob Lowe?

[manofsteel1979]

This is how I feel. I think his aging should slow to a crawl once he hits 50. This makes sense to me. His body will have absorbed enough solar radiation to make it happen by then. I like the way Kingdom Come did it.

That's probably what shaped that idea in my head. I liked the fact that he even eventually develops an immunity to green Kryptonite. It makes sense. His stores become so extensive, that in order to adapt his cellular make up would slightly mutate to the point his cells no longer go through the normal process of cell death and regeneration. He stops aging more or less and Kryptonite radiation is no longer able to infiltrate his cells. He can still be killed by other means like extreme physical trama from beings like Doomsday or Darkseid, magic and enthropy, but a green glowing rock would eventually do no more than give him a slight headache or itchy skin.