Hi Tari,

There are no hard and fast rules when it comes to avoiding yeast. Everyone's body reacts differently, and sensitivity levels vary from person to person, and possibly at different times for the same person.
Certainly you should start off being concervative and avoiding anything that might cause a problem. When you feel well, you can start to reintroduce questionable foods to see if they cause a problem for you or not.
You need to work out two things: 1) can you eat the food at all? and 2) how much can you tolerate?
I would avoid autolyzed yeast extract to begin with since it is made with yeast, and processed as follows:

Autolyzed yeast extract consists of concentrations of yeast cells that are allowed to die and break up, so that the yeasts' digestive enzymes break their proteins down into simpler compounds.

What you are left with after the enzymes have done their job may or may not affect you, depending on the particular yeast proteins to which you are sensitive.
The first thing to do is to feel well, then you can expand your diet.

I hope that helps!

Starting a restricted diet does seem, well restrictive.

The best advice I can give you is to focus on what you can eat, rather than what you must avoid. You will start to see and discover lots of things you can eat.

For protein, you can eat beans of various types, peas, whole grains, cheese ...

For carbohydrates: rice, potatoes, yams, taro root ...

There are lots of "substantial" vegetables such as carrots, squash, fennel root ...

Just keep adding to the list, then work out what you can do with them, of look up some recipes.

Pretty soon you will find that there is a great deal that you can eat!