It’s important to remember that Jared Leto is only 45. As such, he hasn’t exactly had the chance to become ravaged by the fury of age. Even still, it’s kind of shocking to hear that Leto is 45. Not because that's necessarily old, but because when
you think back on Leto’s appearances in films such as Fight Club, American Psycho, and Requiem For A Dream, you begin to realize that Leto looks like pretty much the same person he did 17 years ago.
In Leto’s case, it probably doesn’t hurt that the actor has taken on a variety of roles over the years and, as such, has never really relied on an iconic “look” that gradually began to fade away. Even if he had, though, Leto’s almost non-existent signs of aging would allow him to play the same roles he did almost 20 years ago.