User blog comment:San&Ashitaka/Chapter 57 review/@comment-93.209.37.150-20140506162513/@comment-93.209.8.74-20140506193422

Another thing, yet it may be a no-issue. When ordinary humans become Titans the "ape way", their body is destroyed almost completely and all what remains is a tiny part running the Titan body like a low tier computer program. However Hanji believes that they can completely regenerate their human form including their memories when they eat a Titan shifter. Doesn't have to be a contradiction because the Titan body seems to be based on the original human DNA and also at least two kept a bit of their memories and ability to talk. However as I understood it Ymir was able to remain human within her Titan body for 60 years until she ate Berwick. That's a difference to ordinary Titans. I am aware that they threw Titans at Eren, but that could have been meant just to kill him. There is real point having a Titan suddenly shift back into a human in all that Titan galore hell that it was. They would not have been able to protect him or her.

If the "eat ability" theory of Hanji is true, then it's possible that in the village of Berthold, Berwick, Annie and Reiner children have to eat their parents to acquire the shifter ability. I believe Annie had to eat her dad because in the flashbacks he acted like a creep and said "your dad will ever be together with you".