So wait. (Destiny)

by Ragashingo , Official DBO Cryptarch, Saturday, August 13, 2016, 14:23 (3117 days ago) @ Cody Miller

The Awoken also apparently live a really long time. There's some description text on one of the class items that has an Awoken wondering why they live so long. And yeah, Exos probably have a extremely lengthy lifetime. Cayde-6 (as an Exo), for instance, was body guard to Maya Sunderesh on Venus back during the Golden Age.

At a sheer minimum the Golden Age must have lasted 300 years (or how else would we know our lifespans had tripled?) and it must be 200 years or more since the Collapse (or else The City couldn't have taken "centuries" to build). Given that, and that Saladin is aged but not elderly, I think there's got to be some Light-based slowed aging for Guardians going on here, not just the Golden Age tripling of lifespans.