Atropos is right, MrsLyons - that's definitely the best approach.
I know that hearing about all of these banned foods seem a bit daunting at first, but it's really surprising what you can cook up using the allowed list. Check out the recipe section of the forum for inspiration as the best way to keep on track is with a variety of meals so you don't become bored. There are some great ideas for what to eat on the daily menus thread, too.