So I'm playing fallout 4, I'm at level 26 and since level 24 my health has been regenerating at an obscenely slow rate. To give an example, I can eat a strip of Brahmin meat, it's good for 10 points of health. I'll drop the pip boy and time the rate it takes to regain those points - 80 seconds. Imagine being in a fight with a legendary gunner, hitting a stimpack and seeing the transparent green bar saying "oh yeah here's how much your getting" but having to drop behind a wall for minutes while it fills. It's insane. I'm on standard difficulty, no addictions, no strange perks. I'm a bit confused

Sounds like a bug to me I haven't encountered that when I pop a stim it takes effect immediately.

you sure you are not on survival mode? that regeneration sound like the one you get in survival mode