Is Yeast Gluten-Free?

Celiac.com 09/15/2022 - Among the many questions we get about products, we've recently seen a bunch of questions about yeast. Is yeast gluten-free and safe for people with celiac disease?

Is Yeast Gluten-Free?
Yeast is a fungus that grows in nature, and is used to make many different kinds of foods and beverages. Because yeast is often used to make bread, many people with celiac disease wonder if yeast is gluten-free, and safe for them to eat. The short answer is that nearly all types of yeast are gluten-free, however, there are some exceptions.

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So, can people with celiac disease eat bread made with yeast? Gluten-free bread made with baker’s yeast is safe for people with celiac disease. Many gluten-free breads are made with yeast, and are safe for people with celiac disease to eat. 

Again, most yeast is gluten-free, but some kinds of yeast do contain gluten. 

Yeasts that are Gluten-Free and Safe for People with Celiac Disease:

Active Dry Yeast
Active dry yeast is gluten-free.

Baker's yeast
Baker’s yeast is commonly used in breads. Active dry yeast and instant yeast are types of baker’s yeast. Baker's yeast is gluten-free.

Instant Yeast
Most active yeast needs to be dissolved in water, then added to baking ingredients. Instant yeast is similar to active yeast, but is added directly to dry baking ingredients, without needing to be dissolved in water. Instant yeast is gluten-free. 

Nutritional Yeast
Nutritional yeast is a deactivated yeast, often a strain of Saccharomyces cerevisiae, and is gluten-free.

Torula Yeast (msg)
Torula yeast is gluten-free.

Yeast (except brewer's yeast)
Most yeasts, except Brewer's yeast, are gluten-free.

Yeast Food (msg)

Yeast Nutrient (msg)

Unsafe Yeasts that Contain Gluten:

Brewer’s Yeast
Brewer’s yeast, also called saccharomyces cerevisiae, is not gluten-free unless specified on the product label. Most brewer’s yeast is a byproduct of the beer brewing process and contains gluten from the barley used to make beer. 

There are some brands of brewer’s yeast created using sugar beets and are gluten-free. You should not use brewer’s yeast unless it is labeled gluten-free. 

Autolyzed Yeast Extract / Yeast Extract
Yeast Extract - Autolyzed yeast extract is used primarily as a flavor enhancer in a variety of processed foods such as soups, meats and vegetarian "meats."

While not technically yeast, yeast extract and autolyzed yeast extract may contain gluten from barley. Since manufacturers are not required to disclose the source of yeast extract on the label, it's safe to assume that most autolyzed yeast contains gluten, even in small amounts.

Regarding Marmite, a spread that are made from autolyzed yeast extract, Wikipedia says "In the case of yeast autolysate, however, the yeast proteases are able to degrade most of the gluten. For example, Marmite contains around 30 part per million gluten according to third-party testing, meeting the EU "very low gluten" limit but not the "gluten free" definition. Uniliver reports that no cases of gluten-related reactions have been reported for Marmite." Vegemite, a similar product from Australia, makes a gluten-free version.