I've heard there is an optimal age to donate a kidney. can you provide me more info?

Kidney: This is very complex. First you need to see the compatibly of donor to recipient., then you have to see a nephrologist to confirm compatibly. This is an answer that requires multiple sources.

18-50: Optimal age for a living kidney donor is considered to be between age 18 and 50, however older individuals may be donors if they are in good physical health. Age < 18 is an absolute exclusion criteria in most transplant centers.