Perhaps no other ingredient in human nutrition has been so vilified in recent years as gluten. The internet is full of articles describing the serious health complications associated with gluten consumption (even in healthy people!), and worldwide celebrities are racing to declare the elimination of gluten from their diets and to publish gluten-free cookbooks or recipes. The topic has become so popular in nutrition that the media has begun to attribute incredible negative effects to gluten.
So, what is the reality of gluten consumption?
❌1. "Gluten is stored in fat, especially in the abdomen. I am sure you have heard of the term "wheat belly". If you are reducing weight, it is in this area that weight loss is most difficult. With a gluten-free diet, you will sculpt these areas beautifully as well."
✅ Gluten is a group of storage proteins (specifically prolamins and glutelins) in cereals. These proteins are largely indigestible for humans and the part of the protein that we can break down and absorb is NOT stored in fat predominantly in certain places such as the abdomen. The specific fate of these absorbed proteins (in the form of peptides and amino acids) is the same as the fate of proteins ingested from any other food (e.g. meat, cheese or soy) - it depends on the actual needs of the particular organism. The body uses them for e.g. proteosynthesis and tissue regeneration or converts them into energy. To say that amino acids from gluten are stored as fat predominantly in the abdominal area is FALSE. At the same time, let me add that despite the intense scientific research on gluten-free and low-carb diets in recent years no condition such as "wheat belly" has been described in medicine to date, and no such diagnosis is listed in the International Classification of Diseases of the ICD.
❌ 2. "Eating gluten causes inflammation in the abdomen, it makes it swollen, loosens your abdominal muscles, and does not strengthen your back. Someone can have a sore back, but what is causing it is gluten in their stomach."
✅ In healthy people who do not have problems with gluten consumption (the vast majority of the population, see below), there is no reason why gluten would cause inflammation in their gastrointestinal system. No inflammatory markers are even elevated in people who suffer from a syndrome called non-coeliac gluten sensitivity (or NCGS)! Moreover, paradoxically, people with inflammation in the abdominal area (e.g. peritoneum, colon or appendix) would have their abdominal muscles contracted rather than relaxed, this muscle spasm in the abdominal area during inflammation is referred to as "muscular defense".
❌ 3. "Gluten will glue your intestines!"
✅ The name gluten is actually derived from the word "glue". However, it is about the stickiness of the dough, not about the supposed gluing of the intestines. In fact, the amount of gluten determines the quality of the wheat flour and the dough created, because it is the gluten that gives the product the desired properties (elasticity and proper rising of the dough, the final shape, the stiffness of the pastry, etc.). The better the quality of the flour, the more the dough sticks and the longer the roll will be. However, this does not mean that gluten can in any way "glue" our intestines. In fact, our gastrointestinal system is very well prepared to digest various foods, including those containing gluten, thanks to its surface, digestive enzymes, low pH in the stomach and many other factors.
❌ 4. "Eating gluten is not natural for humans."
✅ Gluten is not a "new chemical", but has been a natural part of the human diet for at least 10,000 years, when humans began to gradually shift from hunting and gathering to agriculture as part of the Neolithic Revolution. But it is very likely that we have been eating gluten for much longer - the oldest surviving records of multi-stage cereal processing date back 32,000 years and come from the Gargano region of Italy. The manual milling and heat processing of (as yet undomesticated) cereals was already in prehistoric times an important source of nutrients that could be easily transported and, more importantly, stored during critical periods (e.g. long winters). It is even possible that this technological know-how to convert wild plants into a long-keeping source of nutrients and energy for later processing and consumption was a significant demographic advantage for modern humans compared to Neanderthals. If a modern man (homo sapiens sapiens) as a species is approximately 45,000 years old, then we can state that modern man has CONSUMED A LARGER PART OF HIS EXISTENCE since the beginning of time in cooked grains. Therefore, do not succumb to misleading claims about the naturalness of various dietary components and their processing with the argument that something is unnatural to man and therefore automatically harmful, when in fact this is not even true at all.
❌ 5. "The increased sensitivity to gluten is due to breeding and genetic modification, which today has made wheat contain much more gluten."
✅ Although this information has even been published by for instance New York Times, the gluten content of wheat has been virtually the same for the last 100 years. There are probably two main factors behind the increased gluten sensitivity - the quantity and quality of gluten. Indeed, the amount of gluten consumed has increased very significantly in the last 20 years, as gluten is now being added to foods that previously did not contain it at all (e.g. meat products and sausages, ketchup and soy sauce, ice cream, and many other foods). A second important factor is probably the different production process of bread and pastry today, where enzymes, yeast, and additives (so-called 'bagging mixes') are used instead of long-term fermentation with bacteria - the so-called 'sourdough' - to maximise production (and reduce price). Sourdough naturally breaks down some of the gluten it contains. Similarly, in the production of conventional bread, the proportion of more expensive rye flour is reduced at the expense of wheat flour, and all these practices actually lead to an increase in the gluten content of baked goods. At the same time, the consumption of bread and pastry themselves is steadily increasing, for instance, the average per capita consumption of gluten in the USA is 5 kg per year. Thus, the main reason for the increased gluten sensitivity is very likely not gluten per se as a natural dietary component, but rather the fact that due to different manufacturing processes, the 'westernization' of the diet and the addition of gluten to other foods, the proportion of gluten in the diet is actually increasing.
Diseases associated with the consumption of gluten and wheat
Currently we distinguish3 different forms of the disease and increased sensitivity to wheat and gluten:
1. Coeliac disease
Coeliac disease is an autoimmune disease caused by gluten intolerance in predisposed individuals and manifested by chronic inflammation in the mucosa of the small intestine. Although references to coeliac disease are found in Greek texts dating back to BC, it was not until 1952 that it was discovered to be caused by the consumption of wheat gluten. Coeliac disease is a genetic disorder that often breaks out in predisposed individuals after a viral infection. Nowadays, it is diagnosed by a positive genetic test, a biopsy of the small intestine, or antibodies to gluten in a serological test. The mechanism of pathogenesis is the production of anti-gluten antibodies by the organism, which cause extensive autoimmune inflammation of the small intestinal mucosa. This can be so extensive with non-adherence to a gluten-free diet that the intestinal villi become obliterated and the surface area for absorption of nutrients into the body is reduced. This is associated with the most common symptoms - bloating, diarrhoea, lack of appetite, fatigue, stunted growth and development in children, malnutrition, etc. Incidentally, due to the reduction of inflammation and the improved absorption of nutrients and energy in the gut, people can often start to gain weight when switching to a gluten-free diet. Particularly serious are the consequences of untreated coeliac disease, which can include anaemia and osteoporosis, cancer of the lymph glands and others. However, the intensity of the problems is very individual and a large proportion of patients have mild and non-specific symptoms. Coeliac disease is incurable, but by following a gluten-free diet the symptoms (including inflammation in the gut) disappear. The prevalence of coeliac disease in the population is between 0.5-1%.
2. Non-coeliac sensitivity to gluten
Also known as non-coeliac gluten sensitivity and NCGS, is a very new disease, which was first described in the 1980s but only "rediscovered" in 2010 in connection with the popularity of gluten-free diets. However, at present, the scientific and medical community is still not unanimous as to whether this syndrome exists independently.
In fact, patients do not suffer from any mucosal inflammation, so the syndrome cannot be proven on histology by biopsy of the intestinal mucosa, nor serologically from blood sampling, because patients do not have elevated antibodies to gluten and there is no (auto)immune reaction.
NCGS patients present with similar (mainly digestive) problems as coeliac disease and affected persons also report depression, headaches, and fatigue. Thus, NCGS is defined as a gluten sensitivity syndrome with many symptoms that improve with a switch to a gluten-free diet in people who do not suffer from coeliac disease or wheat allergy. Some proponents of gluten-free and paleo diets claim that the prevalence of NCGS in the population may be as high as 8%, but since we do not know the process of pathogenesis or the specific diagnosis, the literature estimates the prevalence of NCGS in the population to be around 2-4% at most. On the other hand, there are no long-term health risks associated with non-adherence to a gluten-free diet as there are with coeliac disease. The only diagnostic option is the so-called elimination diet and monitoring of any improvement in subjective symptoms.
3. Allergies
Wheat allergy is no different from other (nowadays, unfortunately, common) allergies in which the body reacts disproportionately to various substances that are commonly encountered in the environment (dust, pollen, animals, wasp stings, etc.). These allergens activate the production of specific antibodies in the body, histamine is secreted and an allergic reaction occurs, which in the case of wheat is most often manifested by digestive problems as in coeliac disease and possibly also by respiratory difficulties and skin reactions. However, these reactions differ from coeliac disease and NCGS in that, as with other allergies, they occur very quickly after eating wheat (within minutes to a few hours at most). Although patients do not suffer any intestinal inflammation or damage to the intestinal mucosa, the allergic reaction can develop into anaphylactic shock, which can be life-threatening. Compared to other food allergies (e.g. seafood, peanut, etc.), wheat allergy is less common.
How many people does it make sense for to eliminate gluten from their diet?
IN FACT, IT'S ONLY ABOUT 5% OF THE POPULATION! These are people with coeliac disease, wheat allergy, and non-coeliac gluten sensitivity. In fact, in 2020, despite intensive research, there was NO scientific evidence that a gluten-free diet is in any way healthier for healthy people, or that switching to a gluten-free diet in and of itself promotes weight loss and fat burning. A balanced gluten-free diet contains the same amount of nutrients as a balanced diet containing gluten, except that a gluten-free diet is more difficult to balance and is also approximately 2x more expensive. In fact, the sale of gluten-free diets is a huge business these days and has grown very significantly in the last 5 years alone (by over 50% in the US to about $16 billion), even though the number of people with coeliac disease, wheat allergy or NCGS has changed virtually nothing in that time. Conversely, there is evidence that adherence to a gluten-free diet in healthy people can have a negative effect on the gut microbiome and the body's immunity.
So, eliminating gluten from the diet of healthy people is not an elixir of health or the key to weight loss, but time and again, a balance must be sought between energy intake, expenditure, and a balanced dietary composition that covers the nutritional requirements given each individual's goals and needs. Eliminating one natural dietary ingredient from the diet (gluten) will not solve anything for healthy people in terms of health or excess weight.
Literature
1) Aranguren, B., Longo, L., Mariotti Lippi, M., & Revedin, A. (2012). Evidence of edible plant exploitation. Pavlov-excavations 2007e2011, The Dolni Vestonice Studies, 18, 170e179.
2) Biesiekierski, Jessica R., et al. „No effects of gluten in patients with self-reported non-celiac gluten sensitivity after dietary reduction of fermentable, poorly absorbed, short-chain carbohydrates.“ Gastroenterology 145.2 (2013): 320-328.
3) Bronski, Peter. “Has the Gluten Content of Wheat Increased Over Time?” No Gluten, No Problem, 12 Mar. 2014, nogluten-noproblem.com/2014/03/has-the-gluten-content-of-wheat-increased-over-time.html.
4) Bucci, Cristina, et al. „Gliadin does not induce mucosal inflammation or basophil activation in patients with nonceliac gluten sensitivity.“ Clinical Gastroenterology and Hepatology 11.10 (2013): 1294-1299.
5) Dieter, B., & Fontinhas, S. (2016). THE GLUTEN MANIFESTO. Retrieved from http://sciencedrivennutrition.com/gluten-manifesto/
6) Drago, Sandro, et al. „Gliadin, zonulin and gut permeability: Effects on celiac and non-celiac intestinal mucosa and intestinal cell lines.“ Scandinavian journal of gastroenterology 41.4 (2006): 408-419.
7) Volta, Umberto, et al. „Non-celiac gluten sensitivity: questions still to be answered despite increasing awareness.“Cellular and Molecular Immunology 10.5 (2013): 383.
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