I would guess this is not true in general since many things do not want to be eaten and so evolve various defense mechanisms. In turn the organisms that eat them may develop counter-measures that enable them to safely digest their meal despite the defense mechanisms but this will depend on the complex evolutionary history of both organisms. Ruminants are adapted to a quite different diet than humans for example.
I would guess this is not true in general since many things do not want to be eaten and so evolve various defense mechanisms. In turn the organisms that eat them may develop counter-measures that enable them to safely digest their meal despite the defense mechanisms but this will depend on the complex evolutionary history of both organisms. Ruminants are adapted to a quite different diet than humans for example.