Getting the Facts Straight // Gluten

Gluten – A vicious monster or just an innocent bystander?

Over the past decade, gluten has become a rather controversial topic that has taken the world by storm. Gluten-free diets have increased in popularity, especially with the publication of books such as Grain Brain and The Real Meal Revolution, which promise that all of your health woes will be over if only you would just choose to cut gluten out of your diet and claim things like: 

…gluten and carbs are destroying your brain...


…wheat is the single largest contributor to the obesity epidemic – and its elimination is key to dramatic weight loss and optimal health...

At face value, these books, as well as the countless blogs, documentaries, personal testimonies, and other forms of media discussing gluten, seem to make a lot of sense. However, when we dive deeper into the research it’s quite clear that the topic is not quite as well understood as those claims make it out to be. In fact, new research has failed to support theories suggesting that non-coeliac gluten sensitivity is real, and recent studies suggest that the digestive and systemic issues that many of us experience could be related to things like food additives, anxiety around gluten-containing foods, and irritable bowel syndrome (IBS). Needless to say, there is a lot of confusion and questions surrounding the true health benefits of eliminating gluten from the diet.


I hope that you can read this post from an objective point of view, and read through and listen to some of the references that I’ve cited at the end of this piece to gain a better understanding of the evidence as we currently understand it. I understand how confusing nutrition-related information can be and am writing this piece without judgement because I’ve wrestled with this topic too. For a number of years, I actively avoided gluten and experienced relief from bloating, GI discomfort, and so-called ‘brain fog’. Over the past couple of months, however, I have come to realise that although for a time avoiding these foods may have provided some kind of perceived benefit for me, gluten was never the agent to blame and the anxiety and fear that I experienced around food caused me far more distress and discomfort. I haven’t had time to share my story on my own blog yet, but this podcast episode is worthwhile listening to if you can relate to experiencing anxiety around food. Having said this, I don’t know your personal health struggles or your lived experience, but I do want to highlight some of the more robust scientific evidence surrounding gluten as opposed to sensationalist pseudo-truths.

What is gluten?

Gluten is the general name for a family of storage proteins that are found in varieties of wheat (spelt, farina, faro, durum, kamut, khorosan, einkorn), rye, and barley. It is responsible for providing stickiness and elasticity to doughs used to make bread and other baked products, and is relatively indigestible by the human gut. The two main components of gluten are glutenin and gliadin. Common food sources of gluten include:

  • Grains (listed above)

  • Breads, crackers and biscuits

  • Soups, gravies and sauces

  • Pasta, cous cous

  • Breakfast cereals

  • Salad dressings

  • Beer

  • Soy sauce

  • Some processed meats

Gluten is also found in products you wouldn’t expect, including lip balms, lipsticks, hair and skin products, toothpastes, supplements and vitamins, and even some medicines.

What about oats?

Oats do not naturally contain any gluten, however, they are considered to be a potential source of gluten due to cross-contamination when they are grown side-by-side with or are processed using the same machinery as any gluten-containing crops such as wheat, barley, and rye. Patients with coeliac disease are advised to only consume certified gluten-free oats, and non-coeliacs may complain of symptoms related to eating oats that may actually be related to factors such as the inability to digest oat fibre (an IBS-related irritation), or the development of an immune response to oat proteins.

Gluten in the body

As mentioned, gluten is made up of two main proteins, gliadin and glutenin. During digestion, the body normally breaks down proteins into their individual building blocks known as amino acids either on their own or as groups of two or three (known as di- or tri-peptides).  Our current understanding is that gliadin peptides aren’t broken down into their amino acid components because we lack the enzymes needed to digest them. It is the absorption of large gliadin peptides that has been suggested to cause an immune response in the body and may result in irritation in the gut and induce changes such as:

  • Opening of the tight junctions that control what enter and exits the small intestine

  • How the small intestine communicates with the immune system

  • Increased cell death

  • Damage to gut epithelial cell structure

Although ‘leaky gut’ caused by gluten sensitivity is a popular theory in the blogosphere and even within the scientific community, there is limited research at present supporting the idea that gluten is responsible for causing this within the majority of the global population.

Coeliac disease

Coeliac disease (CD) is a serious autoimmune disease, which is a condition that develops when the immune system mistakenly defends the body against cells that are not actually harmful to the body. It affects 0.7-1% of the population worldwide and is largely caused by the presence of specific genes in an individual. You are at higher risk of developing CD if you have a close family member that also suffers from it, however, the exact triggers that cause it to develop are largely unknown. In the case of CD, gluten is recognised as a threat to the body. When it is consumed by a CD sufferer the body sets out to damage and destroy villi, which are the teeny tiny projections that line the small intestine that are responsible for absorption of nutrients into the bloodstream. Without healthy villi, the small intestine can’t properly absorb nutrients and this can result in a variety of nutritional deficiencies if CD is not treated. CD symptoms are very severe, and can include:

  • Abdominal bloating and gas

  • Chronic diarrhoea

  • Constipation

  • Pale, foul-smelling stool

  • Stomach pain

  • Nausea and vomiting

If not treated correctly CD can result in poor growth and development, short stature, irritability in mood, anaemia, and weight loss. With proper treatment and the complete elimination of gluten from the diet, patients with CD are able to recover and not experience long-term nutritional deficiencies.

Wheat allergy

A wheat allergy is an immune response to any of the proteins that are present in wheat. This includes, but is not limited, to gluten. Wheat allergy symptoms include nausea and vomiting, diarrhoea, hives, mouth and throat irritation, nasal congestion, eye irritation, and difficulty breathing that can result in severe anaphylaxis, similar to many other food allergies. Symptoms generally begin within minutes of consuming wheat, and individuals with a wheat allergy may or may not be allergic to other gluten-containing grains. Wheat allergies are more common in children than in adults, and up to 65% of children outgrow it by the time they turn 12 years old.

Non-coeliac gluten sensitivity

Non-coeliac gluten sensitivity (NCGS) is a condition that can occur when the body is unable to properly digest or break down gluten proteins. There is conflicting research when it comes to non-coeliac gluten sensitivity, with some experts arguing that it is not a real condition. Symptoms of NCGS range from mild discomfort to symptoms experienced by coeliac patients, but unlike coeliac disease NCGS does not result in damage to the small intestine. The tricky thing with NCGS is that there is no test that can provide a positive diagnosis, but it is generally accepted as the problem in people who experience negative symptoms after eating gluten-containing foods whilst having tested negative for both coeliac disease and wheat allergy. The most commonly reported symptoms of NCGS are:

  • Mental fatigue and ‘brain fog’

  • Fatigue

  • Gas, bloating, and abdominal pain

  • Headaches

The term first became popular in 2011 when this paper was published in The American Journal of Gastroenterology that concluded that “…gluten is indeed a trigger of gut symptoms and tiredness”. However, in 2013 the same researchers were unable to reproduce results when they conducted a more robust, double-blind crossover trial documented in this paper. This new research found that there were in fact: 

…no effects of gluten shown in patients with self-reported non-celiac gluten sensitivity after dietary reduction of fermentable, poorly absorbed, short-chain carbohydrates

They went on to suggest that NCGS should rather be viewed as a variant of IBS not triggered by gluten, but rather by poorly absorbed fructans and galactans found in gluten-containing foods.

Whoa, that’s a lot to take in. Let me try to break it down into easier to digest chunks of information.

  • Fermentable, poorly absorbed, short-chain carbohydrates’ are more commonly known as FODMAPs.

  • FODMAPs are carbohydrates that the human body is unable to digest and thus become available for fermentation in the gut by our intestinal bacteria.

  • FODMAPs are known to cause a many of the symptoms as NCGS, such as bloating, wind, cramping, and diarrhoea, particularly in individuals with IBS.

In this follow-up study, the researchers conducted the exact same study as before, except they eliminated FODMAPs from both the gluten-free and gluten-containing diets of test subjects throughout the study. They found that there were no effects of gluten on the test subjects and that in fact, it was the FODMAPs that may have been the cause of discomfort that had originally been attributed to gluten.

What should I do about gluten then?

If you find that consuming gluten-containing foods results in severe, unpleasant symptoms, it is a good idea to seek out help from a qualified medical professional such as a GP, allergist, or gastroenterologist, who can run the appropriate tests and help you come to a diagnosis. Now I know that this can be expensive and potentially frustrating, but it is important that you rule out any possibility of having coeliac disease, wheat allergy, irritable bowel syndrome (IBS), bowel of ovarian cancer, or any other serious gastrointestinal problems before you take things into your own hands.

Having said that, you most likely know your body better than anyone else. If you find that eliminating gluten-containing foods from your diet helps you feel better, that’s ok, as long as you include enough other fiber-filled ingredients on a daily basis to help promote good digestive health. If avoiding gluten becomes obsessive or something that brings intense fear and anxiety into your life, affecting your relationship with food, then I am inclined to suggest that the anxiety is causing more damage than gluten itself. If you do embark on a gluten-free diet it can be a bit daunting, but don’t worry, there are plenty of other foods that you can enjoy and there are a few simple steps that you can take to make it easier for yourself.

First, start reading the labels on everything you choose to buy from the shops. Gluten hides in the most unexpected places. Second, start eating whole, healthy foods that can be cooked from scratch at home. Avoid processed products, cereals, and gluten-containing grains, and as a rule of thumb rather choose to eat foods that are naturally gluten-free, rather than processed products with the label gluten-free on them. Choose to eat things like:

  • Fruits, vegetables, and tubers (e.g. sweet potato)

  • Beans and other legumes

  • Seeds and nuts

  • Eggs, meat, and dairy

  • Oils and vinegars

  • Non-gluten containing cereals – buckwheat, millet, teff, quinoa, GF oats


For the vast majority of us, avoiding gluten is unnecessary, and there is no robust research that suggests that avoiding gluten is healthier for the general population, or that following a gluten-free diet will be associated with better health. For those that experience serious health conditions related to gluten consumption, removing it from the diet can be beneficial. Wheat allergy, coeliac disease, and non-coeliac gluten sensitivity are distinctly unique conditions, and it is important to rule out rule out ‘red flags’ and undergo proper testing and diagnosis by a qualified expert if you do experience serious symptoms when you eat gluten-containing foods. Understanding your own body is important, so if you know that gluten-containing foods aren’t great for your body and choose not to eat them that’s ok. If you do choose to eliminate gluten, make sure to include a variety of other fibre-rich foods in your diet including veggies, fruit, legumes, and non-gluten containing cereals rather than highly processed gluten-free products.


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  2. NHS UK. Coeliac disease [Internet]. 2016 Dec 4 [cited 2018 Apr 3]. Available from:

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  5. Haboubi NY, Taylor S, Jones S. Coeliac disease and oats: a systematic review. Postgrad Med J. 2006 Oct;82(972):672-678.

  6. Biesiekierski JR. What is gluten? J Gastroenterol Hepatol. 2017 Mar;32 (S1):78-81.

  7. Pietzak M. Celiac disease, wheat allergy, and gluten sensitivity: when gluten free is not a fad. J Parenter Enteral Nutr. 2012 Jan;36(S1):68S-75S.

  8. Staudacher HM, Gibson PR. How healthy is a gluten-free diet? Br J Nutr. 2015;114:1539-41.

  9. Biesiekierski JR, Newnham ED, Irving PM, Barrett JS, Haines M, Doecke J, Shepherd SJ, Muir JG, Gibson PR. Gluten Causes Gastrointestinal Symptoms in Subjects Without Celiac Disease: A Double-Blind Randomized Placebo-Controlled Trial. Am J Gastroenterol. 2011 Jan;106(3):508-14.

  10. Biesiekierski JR, Peters SL, Newnham ED, Rosella O, Muir JG, Gibson PR. No effects of gluten in patients with self-reported non-celiac gluten sensitivity after dietary reduction of fermentable, poorly absorbed, short-chain carbohydrates. Gastroenterol. 2013 Aug;145(2):320-8.

  11. PODCAST: A Personal Story of How a Perceived Gluten Sensitivity Masked an Eating Disorder – Paige Smathers & Christy Harrison