Comment by tjr

I think you can do a whole lot better than the lunch in the opening paragraph pretty easily.

It need not be all-or-nothing. I've been improving my diet for 10 years, as I started to learn more about nutrition.

Instead of a Crustable sandwich, get some turkey at the deli counter and some prepackaged whole wheat bread. Still processed, but better. Maybe after a while, move to getting bread from some whole food bakery or something. If you don't have time or money to jump all in, start taking steps.