Welcome and good day!  I’m continuing to write up my studies on brewer’s and nutritional yeasts as supplements.  (Don’t use this as medical or treatment advice.)  They are very, very similar products, and today I hope to clarify how they are alike and how they are different (as I understand it).  The distinctions between the two are muddier than a farm boy’s boots in the springtime.  Many supplemental items called “brewer’s yeast” are prepared in the same fashion now as “nutritional yeast,” and there seems to be no standard on what it takes to be called “brewer’s yeast” or “nutritional yeast.”  Where once only nutritional yeast had vitamin B 12, now both may.  Or may not.  If ever reading labels was important, it is crucial in the case of brewer’s and nutritional yeast.  I can’t stress that enough.

I’m sorry for stating the obvious.  Brewer’s yeasts and nutritional yeasts are yeasts.  Yeasts are fungi (plural of fungus), like the mushrooms you eat and the molds you clean out of your shower, but yeasts have just one cell.  They are everywhere, occurring naturally on the skin of fruits (like grapes and plums), circulating in the air (like those captured to make a true local sourdough bread), populating the soil, and even residing in and on us.  As a kid, I was always fascinated by the strange fact that fungi are neither plants nor animals.  (The human brain is always trying to box things, isn’t it?)  Humans figured out the advantages of domesticating yeasts, and thus we have wine, beer, and bread.  Yeasts metabolize sugars into alcohol and carbon dioxide.  Yeasts need a lot of the same vitamins and minerals we need to survive and reproduce, like most, but not all, of the B vitamins (thiamine, riboflavin, and folate).

Brewer’s yeasts and nutritional yeasts are in fact the same yeast.  They are both Saccharomyces cerevisiae.  You may read that brewer’s yeast and nutritional yeast are different things.  We will get to their differences later, but for now let’s talk about their same-ness.  They are both the yeast called Saccharomyces cerevisiae (S. cerevisiae).  The same yeast is used to make brewer’s yeast supplements AND nutritional yeast supplements—the same.  This versatile yeast Saccharomyces cerevisiae can be used to brew beer, bake bread, and ferment sweetened tea to kombucha, although other yeasts and bacteria can be used along with it to develop desired characteristics of specific foods or drinks.  (Saccaromyces boulardii in kombucha is a strain of S. cerevisiae.)  Different strains of S. cerevisiae exist, and these different strains are very important for imparting different flavors and qualities to the products they are used to create.

When sold as supplements, brewer’s yeast and nutritional yeast are inactivated, unlike the active yeasts used to make bread (baker’s yeast), beer (brewer’s yeast), and kombucha (S. boulardii).  The supplement forms are not “alive.”  The yeasts used for supplements are cultured and then they are inactivated, dried and ground up.  They cannot reproduce, and they cannot cause any type of infection.  You could not use the supplement called “brewer’s yeast” to make a home-brewed beer.  It couldn’t do it.  It is not alive.  You would need an active form of brewer’s yeast.  The yeasts needed for brewing beer, kombucha, and making bread must be live forms, termed “active yeasts.”  The loose terminology makes understanding a bit challenging.  When you read terms such as Saccharomyces and brewer’s yeast, you need to determine if active or inactive yeasts are being discussed!  Saccharomyces can be sold as a probiotic, in which case it is alive, but it is not “brewer’s yeast” or “nutritional yeast,” even though it is the same organism.  Another term you may come across is “spent yeast”; this refers to a yeast that has not been inactivated, but it has been “used” to do a job (like make beer).

• Active yeasts: Live and able to reproduce. Capable of doing their jobs in food production.
• Inactive yeasts: Not live and not capable of reproduction.
• Spent yeasts: Yeasts that have been used to produce food and drink and are no longer needed.  Some brewer’s yeast supplements are made from spent yeast.  Some spent yeast goes to livestock.  It is usually very bitter and requires de-bittering for consumption.
• Brewer’s yeast:
  1.  It can refer to live S. cerevisiae to be used for brewing.
  2.  It can be spent brewer’s yeast (S. cerevisiae) that is deactivated and ground for supplements.
  3.  It can refer to primary grown S. cerevisiae that is called brewer’s yeast.  (See more below.)
• Nutritional yeast: S. cerevisiae that is grown primarily for supplemental use (so it has been inactivated and ground up), mostly on sugar beet or sugar cane products (molasses).  Usually this name implies that vitamin B 12 was added.

Brewer’s yeasts and nutritional yeasts used for supplements are now usually “primary grown.”  Primary grown refers to the idea that these Saccharomyces yeasts were grown specifically to be made into supplements.  Brewer’s yeast has been used for a long time as a supplement.  At first, it was available only as a by-product of brewing beer, and its nutritional highlights were second to the flavor of the beer it produced—kind of a lucky chance find!  Nutrition in waste.  To taste palatable, it had to have the bitter flavor removed.  Now, however, supplemental brewer’s yeast is often grown specifically (primary grown) for use as a supplement, and much thought is given to its nutritional content and taste!  Despite its name and history, it is no longer solely grown in beer and unless it has been, will not require de-bittering.  Nutritional yeast, as far as I could find, has only been grown for supplementation purposes (primary grown).

Brewer’s yeast and nutritional yeast can be grown using different plant derivatives:  sugar beets, sugar beet molasses, sugar cane molasses, barley, and malt.  Brewer’s yeast can be grown on any of these, and so you must clarify which is used, particularly if you have issues with gluten!  Nutritional yeast is usually broadly categorized as gluten-free because it is usually grown on sugar beets, sugar beet molasses, or sugar cane molasses–not grain.  However, I think it is vitally important that you verify gluten status with the supplement maker, whether you are using brewer’s yeast or nutritional yeast.  I don’t think you can be too careful.  For example, I purchased some Swanson’s brewer’s yeast, and its internet ad stated it was made from sugar beets.  Gluten-free, right?  (Wrong.)  The container I received did not state “gluten-free,” so I called to determine its status.  The woman told me they could not verify that it was gluten-free because they get their yeast from different producers, and it is possible that some could have been grown on grains.

If you are taking either brewer’s yeast or nutritional yeast to get a specific nutrient, such as chromium or vitamin B 12, it is crucially important that you read the label.  Traditionally, brewer’s yeast was rich in chromium, but the newer supplemental brewer’s yeasts which are primary grown may not even have chromium!  (Usually, nutritional yeast does not have chromium.)  Many vegans rely on nutritional yeast for vitamin B 12, but unless the container specifically says that it has vitamin B 12, it cannot be counted on!  Do not assume that all nutritional yeasts have vitamin B 12.  Do not assume that all brewer’s yeasts have chromium.  Read every label, every time.

There is so much more to share!  In the next post(s), I’d like to discuss more specifics about the nutritional content of these supplemental yeasts and some additional points to consider (glutamates and GMO issues).  Until then, take good care!

Terri

A note on sources:  I cannot count the numerous sources I read to piece this information together.  At the end of the series, I am going to list all the pertinent sources.  They take up a lot of space, and so I don’t want them on each post.  However, feel free, at this time before I have the sources listed, to ask me where to find a piece of information.  I don’t mind.