The more you devour, the more powerful you grow. But in the process, your essence is blended with those of your prey.
If you were to lose your flesh, the souls you had come to harbor may break free and coalesce into distinct voidsent once more.
And before you yourself return, your own soul might be devoured by your enemies or your erstwhile prey. A fate more likely for stronger beings, who require more time to regenerate.
However, even assuming you survive the process, it's highly uncommon to return as you were.