What happens if a human eats the human human fruit??
You can find the answer at the Hito-Hito no Mi page...
"This fruit's ability is not effective for humans, as if one ate it, they will not gain any abilities, but all the weaknesses of a normal Devil Fruit user. Oda jokingly stated that the human eater would perhaps gain some enlightenment, finding themselves."
You can find more answers from me: Oda may have said that in an SBS, but one person has eaten a version of the Hito Hito no Mi - Sengoku. Epithet "Buddha", so in a way he is enlightened.
Sengoku has eaten the hito hito no mi model: budda, like other zoan devil fruits, it has more models, and chopper ate the hito hito no mi model: human
Nothing, You Just Can't Swim No More
What do you think?