Well, none of those foods are great for you.
Bread -- see if there's a good bakery near you, and get loaves of whole grain bread (not whole wheat), and eat that instead. Some whole grain breads taste awful, but we have a bakery that does it just right.
Pasta - Try eating whole wheat pasta instead of white pasta. It takes a bit longer to cook, but it's much better for you.
Potatoes - OK, but mostly an empty starch. Try substituting squash.
It's not that you can't ever eat white bread, white pasta, and potatoes -- just make them more of a "cheat" meal than a regular item.