>>40646996 (OP)Prions disease mainly(mild brain damage via RNA/proteins), but also several other factors having to do with health; There's also the risk of diseases from the consumed to be passed down the same as any animal. Most humans can't really consume other humans without there being long term side effects that catch up with you eventually. In some extreme survival scenarios where people resort to cannibalism there isn't always recorded cases of health issues. So if done infrequently in rare circumstances it's usually not fatal. But serial cannibalism giving you brain damage is verifable scientific fact.