Nutritional Yeast or Brewer's Yeast by Ray Sahelian, M.D.

Nutritional Yeast is used as a supplement. It is a deactivated yeast, usually Saccharomyces cerevisiae. Many people take nutritional yeast as a source of protein and B vitamins. Nutritional yeast has a similar appearance to brewer's yeast but has a different taste. Nutritional yeast has a nutty, cheesy, creamy flavor which makes it popular as an ingredient in cheese substitutes and comes in the form of flakes, or as a yellow powder similar in texture to cornmeal, and can be found in the bulk aisle of most natural food stores. Choose nutritional yeast if you do not like the sometimes bitter taste of brewer's yeast. Nutritional yeast is also high in B vitamins and protein; however, this deactivated yeast is not created through beer making and has a more pleasant, cheesy flavor.

Brewer's yeast vs nutritional yeast
Brewer's yeast, usually a byproduct of beer making, can be added to soups, stews, salads and more for it's nutritional value. It has a high content of B vitamins.

I have some inquiries about Brewers Yeast that is taken internally for nutritional or medicinal uses. Is it active or deactivated? Please explain the difference between the two cases. And if it is deactivated, how is the deactivation? Does the deactivation destroy vitamin B complex? Can we take the active brewers yeast internally?
   Brewer's yeast is deactivated through pasteurization thus killing the yeast. It has a high content of B vitamins and can be taken internally.

questions
Q. I am an alternative practitioner for over 20 years. I found your site by accident. How wonderful to find such a frank discussion about many things and that you don't hide behind your degree. Although we do not agree on all things, I thank you for doing so much work to bring these things to availability so that people start thinking about it. Although I realize you mention a good B-complex product, I found something missing in the discussion on B vitamins: Nutritional Yeast. It contains the entire B-Complex, untampered with, and bio-available. I suggest it to everyone who has an afternoon slump. A quarter cup of nutritional yeast flakes in a little milk or OJ may taste funny, I tell them, but the taste grows on you when you see what it does for you. I've had people ask about avoiding yeast so that their candida doesn't get worse. I don't think the Yeast Connection has it right. Yeast does not feed yeast. Sugar and other concentrated carbs feed yeast, and of course the "yeast" in the body is an overgrowth of a ubiquitous item in the body, totally different from yeast in bread or nutritional yeast, which actually originally was called brewer's yeast and was the leftover dregs of the live yeast used in brewing. Last but not least, for education, I plan to place a link to your site on my links page. Please take a look at www.quackcenter dot com/links.html and let me know if you'd rather I didn't. I will say the following: "Although Dr. Ray Sahelian and I do not see eye to eye on all things, he has done a huge amount of work and assembled a tremendous nutritional knowledge base which I invite you to explore. I consider his site to be on a par with the above link." ("the above link" is to a site called Alkalize for Health)