I'm having trouble adjusting the health of my follower NPCs. I set it to something crazily high, like 1000, save the .esp, and try it out in-game, but every time I test it out, the NPC acts as if they have 50 health. This is a big problem for me because even if I set the NPC to essential, they lose what little health they have very quickly, drop to one knee for the longest time and I may as well have no follower at all.

Follower health wont reset immediately when you load a save game. The best way to have changes to a follower take effect is to make a save game before they even start following you, and then load that save game to test your changes.

You might, alternatively, be able to use a little workaround and see if the changes work: open the console, click your follower, and type "disable" and enter, followed by "enable" and enter. This might work to force them to re-evaluate their stats, but I can't say for sure.

Thank you, I'll give it a try.