Islam abhors cannibalism as well. To quote al-Ghazali:
We say that if a little piece of the flesh of a dead human being fell into a cooking pot, be it the weight of a dānaq [sixth of a dirham], the whole [pot’s contents] would become prohibited: not because of being impure, for the correct [opinion] is that a human being does not become impure by death, but because eating it is prohibited by virtue of its inviolability rather than by being considered filthy.
If a single piece of human flesh falls into a pot, the whole thing is illegal to eat.
Interestingly there is some evidence to speculate that despite the prevalence of ritual cannibalism in Mesoamerica, cannibalism proper was abhorred by at least some of those same societies, implying a disconnect of sorts.
In his younger years, Tariacuri, the founder of the Tarascan kingdom, wanted to provoke the island city of Jaracuaro (which he had been groomed to hate along with the other Lake Patzcuaro citystates) to attack. He had captured and killed a priest and cooked a part of his flesh. He sent a courier to Jaracuaro with it to give to another priest (these priests had names in the original story, but I forgot), on the pretense that the meat was from a sacrifice and that Tariacuri bestowed this gift as a peace offering. The messenger had orders to wait until the priest had eaten all of it, then leave. Just outside the city, he was to pour a bucket of water on another messenger to make it look like he had been sweating profusely.
This messenger was to run back to the temple district and 'warn' the priest not to eat the meat, because it was from a fellow priest and not a sacrifice. Obviously being too late, the priest convulsed and vomited profusely in shock, disgust and horror at what he did.
Tariacuri succeeded in pissing off Jaracuaro, but in his youthful passion he underestimated the military and strategic power of the citystate and was forced into exile along with his supporters -- though he managed a successful conquest of the whole region in his old age when all his older enemies died. Even though this story is told from a Tarascan perspective it does give some potential insight into the psychology of cannibalism; maybe humans really are naturally averse to cannibalism? Usually in societies that practice cannibalism, there's some kind of excuse made, e.g "we're communing with the gods and giving them energy with this transfigured flesh", "I'm taking his mana to become stronger", "this person's soul will live on through me and my fellow eaters" etc. There's usually never a purely predatory "We were hungry and decided to go for Chinese" rationale, except in times of dire starvation in which people typically eat those who are already dead.