Nothing, I think. Graphite is simply carbon, and should not be harmful.
A person who - on average - eat more energy than (s)he uses up will gain weight
They may gain weight or feel sick.
you lose weight and your body eats the muscles to stay alive
nothing happens to a rabbit when it eats asparagus. no worrys! =)
Humming bird eats food which is more than its weight.
It poops
If a person eats too much saturated fat they are at risk for gaining weight. It can also clog their arteries over time.
Will do no harm, I have a cat that eats Dogfish heads.
It depend of what it eats
poop
It will die