Does that mean that the more he overuses his ability, the more his hair becomes white?

Now that you mention it maybe, but I also think that it has to do with his body not being able to withstand that amount of power, and it's kind of straining itself, so every time he uses it, it's either his muscles feel like they're tearing, or his bones feel like they're breaking, and his mind is slowly but surely becoming that more of a doll, but hopefully it's not, I'm praying, but this is cool

I thought his hair turned white because of stress☠

That too

i mean... thats also possible and also yk how other manhwa their hair turned white after being op and shit

i honestly relate to the white hair im stress everyday i swear im gonna have full white hair

Kaneki

Kaneki