system
Given the following post, respond as if you're commenting on Reddit:
human
[Marvel] Seriously, when Wolverine heals large chunks of his body, where does he get the extra mass from?

I've heard people mention "meat space," a dimension made of meat that he can draw from. But, that's just a joke answer, right? How do you seriously explain Wolverine's healing power?
gpt
He transmutes energy into body mass, exactly the same way that normal cellular growth does, just really, really fast. Some of that energy comes from normal metabolic sources (i.e., the sugar and fat he's already got stored in his body, just like normal), but most of it comes from the same energy-collection ability that all Mutants possess. So, essentially, it's the same source as where Jean Grey gets the energy to move large objects remotely, where Scott Summers gets the energy to project beams of kinetic force from his eyes, and where Kurt Wagner gets the energy to rip holes in the fabric of spacetime. 

All mutants crib energy from somewhere.