Use of bleach in the flour industry poses a lesson for cannabis producers

Is mass gluten consumption the root cause of celiac disease, or is heavily processed food, such as bleached flour a culprit? (1, 2) Perhaps the answer to this question can teach licensed cannabis processors and cultivators (LPs) a lesson about respecting the plant.

Certain products have been banned in the flour and cheese industry in the UK, as well as most other countries in the world – including China. (3, 4) Despite their widespread restricted status, benzoyl and calcium peroxide are two bleaching agents still used in the North American flour industry. Yet, the pharmacology of these processed food ingredients is dubious, especially for celiac and other autoimmune diseases, to say the least. (5, 6)

Processed goods – food, cannabis, and disease

Different methods are used to solve different problems that occur with consumable goods, especially food. Controversially, this leads to heavily processed goods in the market. Whereas the cannabis industry experienced years of repression, and with a sudden green light, the community had to resolve a host of problems without adequate time to evolve. Vape pens had to be formulated to fit the model of convenience, but that caused the same issues of oxidation as the flour industry. Similar to the packaged food market, some cannabis processors experimented with and may have begun to add substances to modify, prevent, or preserve color that we now know contribute to disease and mortality.

benzoyl peroxide as flour bleach
A benzoyl peroxide gel is used to treat ACNE. Canada and United States also allow this product in food but restrict the allowed quantity (150mg per kilogram in Canada, for example). (7, 8)

How do you get celiac disease?

Approximately one percent of the global population has celiac disease, but the prevalence varies depending on race and ethnicity. (9) In summary, the body will produce antibodies that respond negatively and violently to gluten.

Celiac disease is genetic, which means it must be donated from one generation to the next. People can live with an asymptomatic genetic predisposition to autoimmune disease, but symptoms can still develop later in life. Gluten consumption can cause that onset. However, the microbiome’s response to different processed food has major implications towards the development and severity of symptomatic celiac disease. This gives flour processed with bleaching agents a causative link to the creation of those symptoms.

A consumable product’s first marketing hitch is aesthetics. But, attempts to work around the concept of beauty and shiny things have allowed specific toxins into common processed products. Unfortunately though, one of the ingredients in certain food that might trigger celiac disease, on par with mass gluten consumption, is a bleach persistently used in the North American flour industry. (8) The concern for benzoyl peroxide is due to its effect on flesh and gut bacteria.

Why is flour bleached or the colour of cannabis modified?

The flour and cannabis industries have both struggled with spontaneous degradation and the colour of their respective products. Vitamin E acetate found its way into vape pens formulations as an attempt to prevent colour in cannabis extracts from shifting to pink after a few months (we will discuss this in a future article). Generally, the public and processors have begun to give greater respect to the plant, whether that be wheat or cannabis.

benzoyl peroxide adverse reaction
Adverse reaction to benzoyl peroxide – an ingredient still used in the American flour industry. Courtesy of James Heilman, MD. Wikipedia. 2011.

Benzoyl peroxide is used to chemically age flour beyond the degradation state—but only in North America. Most of the world has banned this bleaching agent, and some nations have even restricted its use in ACNE creams. It was banned in flour production in China in 2011 after the UK limited its use a decade earlier. (2, 10) Widespread restrictions have been implemented because benzoyl peroxide causes cancer since it produces free radicals (1) – but that’s not all. Benzoyl peroxide can cause skin irritations but it is also an antibiotic, and innate immunity is synonymous with an antibiotic response.

Celiac disease, your microbiome, and mass gluten consumption

People that have celiac disease have a large amount of an enzyme, elastase. When this enzyme breaks down gluten it forms an amino acid, 33-Mer. (11) The wall of the intestine is supposed to be protected when this gluten building-block travels into the gut. In the case of celiac disease, however, 33-Mer can enter into tight-junctions that form the intestinal wall. This allows gluten’s amino acid building-blocks to slip deep into the tissue of the small intestine. In the event of celiac disease, special antibodies will recognize gluten’s amino acid pieces as an antigen (toxin). Ultimately, this is how mass gluten consumption can trigger an innate immune response that causes the body to fight itself.

This innate immune response can produce endogenous antibiotics which can disrupt the gut’s microbiome. But, packaged food contains plenty of excessive antibiotics. There are microbes in your stomach that thoroughly coat your gut which can act as an initial line of defence against toxins, like the amino acids in gluten. In theory, massive amounts of gluten will cause microbiome disruption, or dysbiosis, by forcing your body to produce large amounts of its own antibiotic peptides. (6) And, if you strip the microbial barrier away, this can be the initial root cause of celiac disease. From here, a vicious cycle continues until you stop consuming gluten. (12)

The true root cause, gluten or antibiotics

Processed food can contribute to Celiac Disease via dysbiosis, especially flour bleach
A dysfunctional microbiome can weaken the intestine’s physical barrier, the villi, against gluten. This further impedes the body’s ability to absorb nutrients. Photo courtesy of Cenit et al. 2015.

Extracting from this, we see that antibiotics are the true cause of celiac disease, whether they came from eating large amounts of gluten or processed food consumption. In summary, excessive gluten can lead to the overproduction of endogenous antibiotics, a faulty microbiome, and ultimately celiac disease. (6) Yet, when you stack autoimmune disease rates with diet and agricultural practices, it is clear that gluten and genetics are not the only factors.

Well beyond an antibiotic response, is it also possible that benzoyl peroxide can cause the dynamic wall of the intestine to literally corrode away and become smooth? The bleaching agent does act as a chemical (skin) peel, after all. (1, 13)

Bleach in flour and cannabis tech: a war of attrition

banana trees
Monoculture banana trees growing on a farm look like villi in your gut. Photo Courtesy of Keerikkadans Green Park.

The use of bleach in the flour industry poses a lesson for cannabis producers. But, to swap roles, cannabis’s diversity should be seen as a mentor for the food industry. Banana farms have begun to fall due to the use of monoculture farms that cannot defend themselves against Panama Disease. (14) An industrialized cannabis supply is a metaphoric banana farm since large-scale crops are hardly suitable for the niche market they stand to supply. Only a pharmaceutical model seems to work in this highly processed setting, according to business trends over the last year. Will the manipulation of different tactics that neglect diversity win or lose the common consumer in the long run? Keep in mind that cannabis demands diversity.

Think about the flour producers that utilized peroxide-based flour bleach to hide the imperfection of oxidation from their customers. It is hard to quantify how much the use of flour bleach contributes to celiac disease cases and other complications, but the gluten-free industry inevitably created unhealthy competition for the cereal-grain market. But, why would flour producers intend to create competition that hinders their business? Or, did they create this hindrance by accident?

Food is changing, and while that raises a lot of questions beyond glimmering carrots, it grants us whole new opportunities. Countries are banning ingredients and Kellogg’s announced that they will remove glyphosate in their products by 2025. (15) In place for what? Sadly, we do not yet know. Regardless, will they also ban certain processed foods, such as flour bleach, for the sake of celiac disease patients?

Let us know your thoughts on America’s continued use of flour bleach in light of celiac disease patients in the comments. Are you surprised to learn that China banned a known carcinogen in their food a decade ago that is still used in North America?

Key facts

  • Gluten activates zonulin which increases the intestines permeability.
  • Cereal grain inhibits TLR2 and is an agonist to TLR4 and TLR7.
  • Gluten activates CD4+ and CD8+ αβ T cells.
  • Peroxide compounds function as potent ROS initiators.
  • Flavonoids can inhibit the tumorigenesis caused by benzoyl peroxide. (16.)
  • The ECS functions as a potent ROS mediator.


  1. Slaga, T. J., Klein-Szanto, A. J., Triplett, L. L., Yotti, L. P., & Trosko, K. E. (1981). Skin tumor-promoting activity of benzoyl peroxide, a widely used free radical-generating compound. Science (New York, N.Y.)213(4511), 1023–1025.
  2. Sharma, N., Bhatia, S., Chunduri, V., Kaur, S., Sharma, S., Kapoor, P., Kumari, A., & Garg, M. (2020). Pathogenesis of Celiac Disease and Other Gluten Related Disorders in Wheat and Strategies for Mitigating Them. Frontiers in nutrition7, 6.
  3. China bans two food additives in flour. March, 2011.
  4. Review of Changes in Food and Feed Legislation affecting the UK. July, 2011. Food and Feed Law.
  5. Brynychova, I., Hoffmanova, I., Dvorak, M., & Dankova, P. (2016). Increased Expression of TLR4 and TLR7 but Not Prolactin mRNA by Peripheral Blood Monocytes in Active Celiac Disease. Advances in clinical and experimental medicine : official organ Wroclaw Medical University25(5), 887–893. doi/10.17219/acem/39940
  6. Han, A., Newell, E. W., Glanville, J., Fernandez-Becker, N., Khosla, C., Chien, Y. H., & Davis, M. M. (2013). Dietary gluten triggers concomitant activation of CD4+ and CD8+ αβ T cells and γδ T cells in celiac disease. Proceedings of the National Academy of Sciences of the United States of America110(32), 13073–13078. doi/10.1073/pnas.1311861110
  7. Health Canada. Oct, 2012. List of Permitted Bleaching, Maturing or Dough Conditioning Agents (Lists of Permitted Food Additives). Gov Can.
  8. Sec. 184.1157 Benzoyl peroxide. April, 2020. Code of Federal Regulations Title 21, volume 3. Part 184. FDA.
  9. Catassi, C., Gatti, S., & Lionetti, E. (2015). World perspective and celiac disease epidemiology. Digestive diseases (Basel, Switzerland)33(2), 141–146.
  10. EU REGULATION (EC) No 1272/2008
  11. Ozuna, C. V., Iehisa, J. C., Giménez, M. J., Alvarez, J. B., Sousa, C., & Barro, F. (2015). Diversification of the celiac disease α-gliadin complex in wheat: a 33-mer peptide with six overlapping epitopes, evolved following polyploidization. The Plant journal : for cell and molecular biology82(5), 794–805. doi/10.1111/tpj.12851
  12. Cenit, M. C., Codoñer-Franch, P., & Sanz, Y. (2016). Gut Microbiota and Risk of Developing Celiac Disease. Journal of clinical gastroenterology, 50 Suppl 2, Proceedings from the 8th Probiotics, Prebiotics & New Foods for Microbiota and Human Health meeting held in Rome, Italy on September 13-15, 2015, S148–S152. doi/10.1097/MCG.0000000000000688
  13. Kurokawa, I., Oiso, N., & Kawada, A. (2017). Adjuvant alternative treatment with chemical peeling and subsequent iontophoresis for postinflammatory hyperpigmentation, erosion with inflamed red papules and non-inflamed atrophic scars in acne vulgaris. The Journal of dermatology44(4), 401–405.
  14. Li, Z., Wang, T., He, C., Cheng, K., Zeng, R., & Song, Y. (2020). Control of Panama disease of banana by intercropping with Chinese chive (Allium tuberosum Rottler): cultivar differences. BMC plant biology20(1), 432.
  15. Kellogg Announces Commitment to Phase Out Glyphosate in Wheat and Oat Supply Chains. 2020. As You Sow.
  16. Zhao, J., Lahiri-Chatterjee, M., Sharma, Y., & Agarwal, R. (2000). Inhibitory effect of a flavonoid antioxidant silymarin on benzoyl peroxide-induced tumor promotion, oxidative stress and inflammatory responses in SENCAR mouse skin. Carcinogenesis21(4), 811–816.