Thank you for your email, and encouraging comments.
We are not aware of which guidelines you are following, but the Daniel diet of the Bible is a simple vegan diet, which would include nutritional yeast, which is an inactive form of yeast, unlike the yeasts use for baking and brewing.
The Jewish sages symbolically associated yeast with sin, because it multiplies rapidly, so it was eliminated during the Passover celebration; however, since nutritional yeast didn't exist in those days and does not multiply, it shouldn't be included within the tradition.
If you are referring to something else, please let us know.
In the Love of the Lord,
Frank and Mary