“Gluten is this generation’s tobacco” – David Perlmutter, M.D.

I’m walking down the aisles of my local supermarket and stumble across the bread aisle. I gaze and eerily notice how many different varieties of bread are commercially available for us to consume but I also realize that I don’t feel any inclination to consume any of it, as if something repels me about our modern-day interpretation of bread. It’s obvious that the ability to expend little to no effort in walking to a supermarket, grabbing a loaf of bread off the shelves and taking it home to enjoy toasted with a dash of Nutella, butter, or vegemite is a luxury our ancestors would’ve gladly accepted over the labour-intensive process of growing, milling, grinding, churning, and baking wheat into bread. However, there are some insidious downsides to this luxury we readily take advantage of that we let fall between the cracks.

Historically, wheat is one the most cultivated grains in the world, being produced in over 100 countries and falling just behind rice and maize but is also one of the newer grains introduced into the human diet as it’s cultivation only dates to approximately 10,000 years ago through the hybridization of emmer (a type of wheat) with the wild grass, Triticum tauschii. Additionally, over 25000 types of wheat grain have developed since its inception, implying the ability to adapt to a variety of temperate environments. The “viscoelasticity” of wheat is a unique feature that is only shared with rye and plays an important role in making leavened bread (bread made using an additive that causes it to rise and ferment), as it allows the entrapment of carbon dioxide released during leavening (Shewry, 2009). 

The wheat grain consists of three main components: the endosperm (80-85%), the bran (13-17%), and the germ (2-3%). The bran is the outer layer of the grain and is rich in B vitamins, fibre, and minerals. However, this part of the grain is separated from the endosperm in the first step of milling. The endosperm contains starch, protein (albumins, globulins, and glutenins and gliadins, the proteins that form gluten), fibre (-glucans), selenium, and the germ contains lipids, protein and is prized and sold separately for its vitamin E content (Šramkova et al, 2009).

To get into the nitty gritty behind wheat’s fall from grace, it’s important to realize that there are a multitude of variables that interplay to drive higher incidences of conditions related to wheat consumption, such as coeliac disease, wheat allergy, and non-celiac wheat sensitivity. Modern agriculture has drastically changed the wheat that we consume today compared to the wheat that was consumed 10000 years ago. Depending on number of chromosomes (ploidy), wheat is classified in one of three categories:

1. Ancient wheat with 14 chromosomes (diploid wheat)
2. Tetraploid wheat with 28 chromosomes (Triticum durum)
3. Hexaploid wheat with 42 hormones (Triticum aestivum)

Hexaploid wheat, being very large in stature, was crossbred with a shorter strain of wheat to improve yield outcomes, which also resulted in major changes in the protein and epitome (antigenic determinant) content of the wheat, including the development of new gluten proteins that were previously not present in wheat and this may have implications in the pathogenesis of gluten-related disorders (Lorgeril & Salen, 2014). 

Coeliac disease is a small intestinal, immune mediate enteropathy characterized by specific autoantibodies against tissue transglutaminase 2 and endomysium, precipitated by exposure to gliadin, a protein that forms part of gluten. Wheat allergy, on the other hand, is an adverse reaction to wheat proteins that can be mediated by wheat-specific immunoglobulin-E antibodies but non-IgE mediated reactions also exist (Catassi et al, 2013). The pathogenesis of non-coeliac gluten sensitivity is unclear but it is possible that other compounds present in wheat such as FODMAPs, can cause symptoms of irritable bowel syndrome that resemble those in non-coeliac gluten sensitivity. Additionally, a decrease in T helper cell numbers and T cell clones expansion, as well as over-expression of HLA-DQ2 and DQ8 serotypes (genetic markers involved in inflammatory responses) have been found in patients with NCGS, indicating involvement of the innate immune system (Asri et al, 2021). 

“the argument in favour of using glyphosate is that humans shouldn’t worry about it because glyphosate only affects plants and bacteria… we are ten times more bacteria than we are human cells. Therefore, glyphosate becomes a major issue for us to be real concerned about.” – David Perlmutter, M.D. 

Gluten makes up the major portion of the protein content in wheat (60-75%) and is comprised by the epitopes that induce immune responses, gliadin and glutenin. It has been found that modern varieties of wheat contain a higher amount of intact T-cell stimulatory epitopes than old wheat varieties, implying that new wheat is more capable of inducing immune reactions than old wheat (Sharma et al, 2020). Additionally, the microbiome has been implicated in the pathogenesis of gluten-related disorders. Stool samples of coeliac patients showed shifts in bacterial populations, resulting in an increased prevalence of pathogenic bacteria. This aberration may interfere with natural mucosal barrier function, increasing the risk of toxic/immunogenic molecules to penetrate the intestinal walls and induce immune responses (Mumolo et al, 2020). 

Research conducted on animal models have postulated negative effects of glyphosate, a herbicide used in agriculture, on intestinal microbiota by killing beneficial forms of bacteria (bifidobacterium and lactobacillus strains), increasing the risk dysbiosis and impaired mucosa function. Lactobacillus strains of bacteria possess proteolytic properties, aiding the breakdown of wheat into less allergenic forms and produce phytase, an enzyme necessary for the breakdown of phytates in grains, which can chelate important minerals. Bifidobacterium can suppress the pro-inflammatory milieu of celiac disease and improve the integrity of tight junctions of intestinal cells and thus reducing epithelia permeability. Additionally, glyphosate may disrupt the activity of protease, amylase, and lipase, which are essential enzymes for the digestion of protein and fat. This implies that glyphosate may interfere with the digestion of gluten, causing larger fragments to pass through the gut and triggering an autoimmune response (Samsel & Seneff, 2014). 

In conclusion, wheat will remain a staple food in the human diet for as long as we live, however, careful attention needs to be placed on how different the wheat we consume today is compared to the wheat cultivated 10000 years ago. Being mindful that the genetic modification and hybridization of wheat, plus the use of herbicides all interplay to form a food source that our digestive system is unfamiliar with, puts us at an advantage to make informed choices that may substantially decrease, if not completely prevent, the chances of developing life-long or difficult-to-manage conditions and unexplainable symptoms.    

References

Asri, N., Rostami-Nejad, M., Anderson, R.P. & Rostami, K. (2021). The gluten gene: unlocking the understanding of gluten sensitivity and intolerance. The application of clinical genetics, 14, 37-50. https://doi.org/10.2147%2FTACG.S276596

Catassi, C., Bai, J.C., Bonaz, B., Bouma, G., et al. (2013). Non-celiac gluten sensitivity: the new frontier of gluten related disorders. Nutrients, 5(10), 3839-3853. https://doi.org/10.3390/nu5103839

Lorgeril, M., & Salen, P. (2014). Gluten and wheat intolerance today: are modern wheat strains involved? International journal of food sciences and nutrition, 65(5), 577-581. https://doi.org/10.3109/09637486.2014.886185

Mumolo, M.G., Rettura, F., Melissari, S., Costa, F., et al. (2020). Is gluten the only culprit for non-celiac gluten/wheat sensitivity? Nutrients, 12(12), 3785. https://doi.org/10.3390/nu12123785

Samsel, A. & Seneff, S. (2014). Glyphosate: pathways to modern disease II: celiac sprue and gluten intolerance. Interdisciplinary toxicology, 6(4), 159-184. https://doi.org/10.2478/intox-2013-0026

Sharma, N., Bhatia, S., Chunduri, V., Kaur, S., et al. (2020). Pathogenesis of celiac disease and other gluten related disorders in wheat and strategies for mitigating them. Frontiers in nutrition, 7, 6. https://doi.org/10.3389%2Ffnut.2020.00006

Shewry, P.R. (2009). Wheat. Journal of experimental botany, 60(6), 1537-1553. https://doi.org/10.1093/jxb/erp058

Šramkova, Z., Gregová, E. & Sturdik, E. (2009). Chemical composition and nutritional quality of wheat grain. Acta chimica slovaca, 2(1), 115-138. https://www.researchgate.net/profile/Edita-Gregova/publication/292395561_Chemical_composition_and_nutritional_quality_of_wheat_grain/links/58c117e04585156790276c3f/Chemical-composition-and-nutritional-quality-of-wheat-grain.pdf