Voting with your fork

Before reading the book, I just ate what my mother cooked for me but after reading the book, I now know that there's more to what we eat than meets the eye. I guess by "voting with your fork" he means that we should be able to choose what we eat and that we shouldn't let the food industry cloud our thinking. For example, I visited my grandmother and she cooks this soup called "Sancocho" and I saw how she made it. There was one type of meat she puts that I forgot the name of, but it was long and it looked like intestines. When I saw it, I kept thinking about what the book said and the author's experience when he skinned the pig. I liked Sancocho but this time, I really felt nauseous and felt the desire to throw up.