Mass consumed not making a difference...

You do realize that people take rat poison to control blood pressure, right? And squirt deadly nightshade into their eyes to do eye exams, right? Mass consumed makes a HUGE difference.

Give a dog a pound of milk chocolate and it'll be mildly sick. Give it a pound of baker's chocolate, which gram for gram contains a huge amount more cocoa, and it'll be a vet visit at minimum. Just cocoa, totally edible. But the mass consumed makes a huge difference.