Update on the gluten-free status of yeast extract

Update on the gluten-free status of yeast extract

Update July 29, 2014 : Based on testing done by Gluten Free Watchdog, I would like to reiterate that it is my recommendation that individuals with gluten-related disorders avoid products NOT labeled gluten-free containing the ingredients yeast extract or autolyzed yeast extract unless the source is confirmed. Please note that if you live in Canada, ALL gluten sources must be declared in the ingredients list. In addition Coeliac UK recently modified their position on yeast extract specifically as it pertains to Marmite (a yeast extract product) stating that the manufacturers have informed them that the product contains, “slightly more than 20 ppm gluten.” 


Individuals with celiac disease and other gluten-related disorders have long been advised to avoid foods containing the ingredient “brewer’s yeast” but not the ingredients “yeast extract” or “autolyzed yeast extract.”

My current recommendation when either yeast extract or autolyzed yeast extract is listed as an ingredient in foods NOT labeled gluten-free is to contact the manufacturer and ask whether spent yeast from beer manufacturing is the source. Here’s why…

In 2010 I tested the yeast extract spread Marmite for gluten http://www.glutenfreedietitian.com/newsletter/is-marmite-gluten-free/. Marmite was assessed for gluten contamination as part of preliminary testing for a planned large study on yeast extract derived from brewer’s yeast (the primary ingredient in Marmite is yeast extract from spent yeast arising as a by-product of beer making). Brewer’s yeast, when used as an ingredient in food, may be a by-product of the beer brewing process and as such may be contaminated with malt and grain.

The planned study has not taken place due to lack of funding. If anyone is interested in helping to fund a study on yeast extract, please contact me.

The results of the testing on Marmite are as follows:

Sandwich R5 ELISA
Extraction One: 28 ppm gluten
Extraction Two: 31 ppm gluten

Lower limit of quantification for this assay is 5 ppm gluten

Competitive R5 ELISA*
Extraction One: 3,700 ppm gluten peptide
Extraction Two: 3,400 ppm gluten peptide

Lower limit of quantification for this assay is 1,250 ppm gluten peptide

*At the time this testing was conducted results of the competitive R5 ELISA were reported as gluten peptides.

Health Canada recently revised their allergen labeling law. Under the new regulations which took effect August 4, 2012, all gluten sources in packaged food products (including barley) must be declared. Barley is now showing up on food labels containing yeast extract. The Canadian Celiac Association (CCA) has done some preliminary testing on yeast extract. As a result of the new allergen regulations and the preliminary test results, the CCA in the latest edition of the Pocket Dictionary Acceptability of Foods & Food Ingredients for the Gluten-Free Diet, is advising individuals with celiac disease to avoid consuming products containing yeast extract when “the ingredient list identifies barley protein as part of yeast extract.”

We do not know at this time how often spent yeast is the source of yeast extract (this is why a large survey of yeast extract manufacturers would come in handy). Unfortunately, in the US barley protein is not included under the Food Allergen Labeling and Consumer Protection Act. So in the US (unlike Canada) there is no way to know from the food label whether the ingredient yeast extract contains barley protein. While this is not cause for undue alarm it is important to clarify with manufacturers whether spent yeast is the source of yeast extract in a food product not labeled gluten-free.

Thank you to Canadian dietitians extraordinaire Alexandra Anca, MHSc., RD and Shelley Case, BSc, RD for help compiling this information.

Copyright © 2013 and © 2014 by Tricia Thompson, MS, RD. All rights reserved. This article may not be reprinted, reposted, or republished without the express written permission of Tricia Thompson.


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Comments (11)

  • Braden Wright Reply

    Thanks for this excellent post, and clarifications! Great insights and distinctions to look out for. It’s been confusing looking at labels on Broth (Chicken and/or Beef). Also brilliant to note when travelling in the States, to understand that differences in food label disclosures.

    February 12, 2017 at 2:38 am
  • Alie Reply

    I can’t eat marmite or vegemite. My version of gluten allergy makes me extremely sensitive. I’ve gotten sick from “gf” products containing “less than 20 ppm gluten”.

    October 7, 2017 at 2:37 pm
  • Gregg Reply

    I am a classic late catcher to my gluten allergy (im 29), refusing to believe i would be sensitive to such thing. Anyways i stopped gluten and dairy, dairy always made my stomach upset and gluten made me bloated and gasy as well as congested.

    So I stopped gluten and diary for a week solid (feeling great), analysed everything I ate, except for Marmite last night. I can tell you I have never felt so ill, i am still suffering today. Headache, nausea.. almost like i have the flu. I didn’t realize marmite has gluten in it, its the only thing that I let slip past my radar. Dont risk eating it.

    November 27, 2017 at 11:51 am
    • David James Price Reply

      I have recently had a gluten reaction after putting Tesco home brand yeast extract on my rice cakes at breakfast time 3 days on the trott around 11:30am on the 3rd day I got stomach cramps after expieriencing indigestion. Also some joint discomfort in my left hip which should dissapear when I go commpletely gluten free after a while. I do not know at this stage if I am cross reacting with yeast. I will find out by eating some gluten free bread with yeast in it. Also if I drink gluten based alcoholic drink I get a headache wich last for 16 hours where the eyes hurt as well. I have been managing gluten intolorance for 4 years 9 months. I cannot bear to have it diagnosed as I cannot bear to go through the pain for 3 weeks whilst the doctors do their test. The doctor says if it is not broken dont fix it, you have done a good job managing it.

      March 9, 2019 at 1:54 pm
    • Jan Cusano Reply

      Would be lovely if you could make chicken soup GF!!!

      June 30, 2020 at 9:33 pm
      • heidi Reply

        I’m not sure if u have access to Swanson chicken broth but they are gluten free.

        December 17, 2021 at 4:23 am
  • Lucille Reply

    I’m a person who has had this since I was 16 and diagnosed when I was 18 and now nearly 20 years later after eating gluten and wheat free products and being on a strict diet i have discovered that even the gluten and wheat free products are making me ill due to that 20ppm that is legalised and lent to be safe to consume

    December 18, 2017 at 9:27 pm
  • Ian McCreey Reply

    I loved marmite! Since being diagnosed 3 years ago have not touched it, read recently if it’s just over 20ppm , near like you would eat it out of a jar it’s above 20ppm you are consuming , but if having it on say Gluten free bread , butter corn crackers etc,
    Your total consumption of what you are eating takes it below 20ppm , is that correct ?

    May 30, 2018 at 5:27 pm
    • Tricia Thompson Reply

      Hi Ian, It is important to understand parts per million. It is a proportion–how many parts out of i million parts is gluten (mg/kg). Each 1 ounce/28 grams of a gluten-free food containing just under 20 ppm of gluten will contain approximately 0.57 mg of gluten. This mg amount of gluten doesn’t change regardless of whether you eat the food alone or as part of a larger meal. When we tested Marmite we found it to contain a level of gluten of approximately 30 ppm intact gluten. It contained higher levels of gluten protein fragments. In the opinion of Gluten Free Watchdog, folks with celiac disease and other gluten related disorders should not eat Marmite.

      June 4, 2018 at 1:37 pm
      • Craig Nixon Reply

        So you seem to be saying to Ian is that having marmite on gf bread, which i assume is much less than 20ppm, does not effectively lower the overall ppm of the gluten for the “food” as you say? Should this not be your actual real world test?

        July 28, 2018 at 8:19 pm
        • Tricia Thompson Reply

          No, this is not what I’m saying. Again ppm is a proportion–how many parts out of one million parts is gluten. Each one ounce serving of food containing just under 20 ppm gluten contains about 1/2 mg of gluten. It doesn’t matter if Marmite is eaten off a spoon or along with a slice of bread, the mg amount of gluten will be the same if the amount of Marmite on the spoon or the bread is the same. Based on our testing, Marmite contains about 30 ppm of intact gluten and far more gluten protein fragments.

          July 31, 2018 at 9:12 pm

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