Gluten – Who Really Suffers from It?

Gluten is a collective term for a group of proteins found in wheat and other cereals. Its specific composition is dependent on various factors such as the type of fertilizer used, the maturity stage of the grains, or the date of harvesting. It consists of fibrous glutenins and prolamines. The most popular fraction is the most allergenic of all proteins - gliadin. Gluten also includes hordein, secalin, and avenin. Despite its often unfavorable associations, gluten can offer benefits, particularly in the baking industry. Its proportion in flour serves as an indicator of baking quality. The higher its content, the more light and delicate the baked goods will be. Gluten is primarily found in grain products such as wheat and its variants, barley, rye, and oats. Although the latter grain contains the least allergenic fraction of gluten and was once considered safe for consumption by individuals on a gluten-free diet, according to FAO/WHO, it is not safe for those diagnosed with celiac disease, dermatitis herpetiformis, or gluten allergy.

Due to the increasing number of cases diagnosed with celiac disease or gluten allergy, more and more people have become concerned about the negative effects of this protein on the human body. There is also an increase in the popularity of the gluten-free diet, which is applied even without prior diagnostic tests for intolerance or allergy. The main goal of eliminating this component is to improve digestion, improve thinking processes, improve hair and skin condition, or reduce body weight. Gluten opponents suggest that gluten may also be a health hazard, and in some cases even a life-threatening one. However, according to current research on food intolerance and allergy, gluten-free diets may also have a negative impact on the body's health. Nevertheless, in some studies, it has been shown that the effects of glucose on the health of many people (e.g. in the case of diabetes mellitus and other diseases) have been significantly reduced, which has had a positive impact on their health. It is worth noting, however, that the main method for reducing body weight should be a healthy and balanced diet with an appropriate energy deficit that allows for weight loss at a suitable pace adapted to health status and individual needs. There are also studies that confirm the positive impact of gluten on healthy people (D. J. Jenkins et al. 1999). It has been shown that a higher intake of this protein in the diet can contribute to lowering LDL cholesterol and triglyceride levels, whose high concentration in the blood is one of the causes of heart disease. Scientists also point to the positive impact of gluten-containing grains on the gut microbiome (G. De Palma et al. 2009). The introduction of a gluten-free diet can lead to changes in the number of certain bacterial species that naturally inhabit the gut. As researchers report, the number of beneficial bacterial strains has decreased, while the number of those that can have a negative impact on health has increased. It should not be forgotten that gluten is provided in the diet in the form of bread, pasta, or other bakery products. These are products that are a good source of dietary fiber, provided that the whole-grain form is chosen. Excluding these products from the diet without medical indication can have many negative consequences, such as digestive problems, constipation, increased risk of type 2 diabetes and obesity.

Gluten can indeed have negative effects on the health of certain individuals. There are 4 medical reasons for using a gluten-free diet: celiac disease, Dühring's disease, gluten sensitivity and non-celiac gluten sensitivity. The worldwide combined incidence of these conditions is approximately 5%. Unfortunately, the similarity of symptoms in the individual disorders makes diagnosis significantly challenging. Currently, three abnormal reactions to gluten proteins in the body are recognized: allergy, autoimmunization, and other immune-mediated sensitivities.

Gluten intolerance disorder is a genetically predisposed condition that affects individuals with genetic predispositions and manifests as a lack of tolerance for gluten. Gladiadyn is the trigger for this disorder. Consumption of gluten leads to a decrease in the intestinal villi, structures responsible for the absorption of digestive products, as well as an increase in intestinal barrier permeability. This is due to the inadequate direct intake of products containing this protein. If left untreated, it can lead to serious disorders of the digestive system and other autoimmune, psychological, and even cancerous conditions. The disorder can occur at any age and has a wide range of symptoms, including abdominal pain, bloating, diarrhea, weight loss, skin inflammation, and anemia. Due to numerous deficiencies associated with impaired intestinal absorption, various other complaints may appear over time, which are often not directly linked to gluten intolerance disorder. In diagnosing gluten intolerance disorder, genetic, serological, and histopathological tests are typically performed, including the removal of a section of the small intestine mucosa. The most effective treatment for gluten intolerance disorder is a gluten-free diet, which must be followed from the time of diagnosis to the end of life. Approximately 0,8% of the population in Poland suffer from gluten intolerance disorder.

Dühring's Syndrome, also known as chronic skin inflammation, is a cutaneous cellulite syndrome with a similar etiopathology to celiac disease, although it is less widely recognized. In this case, most of the symptoms pertain mainly to the skin and not intestinal disorders. This syndrome primarily affects children. The most common symptom is the appearance of red, itchy skin rashes, which can be observed mainly around the elbows and buttocks region. Diagnosis of this syndrome requires the detection of immunological disturbances in the skin and the presence of antibodies directed against smooth muscles. Treatment does not limit itself to the introduction of a gluten-free diet, but also to the application of appropriate pharmacotherapy. Protein tolerance is individual, therefore, in some cases, it is sufficient to only restrict products that are its source, in others, they must be completely eliminated.

The improper response of the body to gluten is not often diagnosed. It is more common to have an allergy to non-gluten wheat proteins. People with an improper response to gluten often experience symptoms from the digestive and respiratory systems. Diagnosis is difficult as available tests are not sensitive enough. People suffering from this condition exhibit different gluten tolerance, so in some cases it is enough to reduce the amount of gluten in the diet, and in others it is necessary to completely eliminate products containing gluten.

Impaired tolerance to gluten is a highly controversial topic in the medical world. This is because there is a large group of patients who, like people with celiac disease, feel very bad after consuming this protein, but in contrast to celiac disease, they do not have villous atrophy. There are also no tests to diagnose this disease. Non-celiac gluten sensitivity is a term used to describe the intolerance to this protein in individuals who do not have an allergy, celiac disease, or Dühring's disease. Symptoms include abdominal pain, diarrhea, constipation, headache, joint pain, and muscle pain. They appear after consuming products containing gluten and disappear after an elimination diet. The process of diagnosing non-celiac gluten sensitivity is very complex, as it requires the exclusion of other diseases associated with impaired tolerance to this protein, followed by a gluten-free diet. If the symptoms disappear after elimination and do not return after reintroducing gluten-containing products, impaired tolerance to this protein can be confirmed. The frequency of impaired tolerance to gluten in the population is estimated to be around 0,5-6%. However, it is important to note that it is not certain that gluten is directly responsible for the gastrointestinal symptoms experienced by people with impaired tolerance to gluten.

Over time, the number of voices increases that a gluten-free diet can significantly improve the health of individuals on the autism spectrum. In many instances, the use of gluten and dairy elimination is proposed. However, as it turns out, scientific studies do not fully confirm the validity of such actions (J. Michałowska et al., 2018). Reviews of studies indicate that the evidence for the effectiveness of a gluten-free diet in this case is weak. In light of the latest scientific publications, the elimination of gluten in the autism spectrum only makes sense if there is a simultaneous identification of intolerance or allergy to this protein.

The existence of one autoimmune disease often influences the occurrence of others. Therefore, people with Hashimoto's disease frequently also have celiac disease, which can affect up to 5-9% of the population. In such a case, a gluten-free diet is necessary, as without it, complications such as loss of intestinal villi and the intensification of the intestinal barrier can occur. The elimination of gluten-containing grains allows for a reduction in the level of antibodies characteristic of celiac disease and also directed against the thyroid. However, similar effects are not observed in patients in whom both diseases have not been diagnosed simultaneously. There is a lack of unequivocal scientific evidence confirming any benefits of a gluten-free diet in Hashimoto's patients who do not have gastrointestinal disease and in whom no gluten allergy or intolerance has been diagnosed. In such people, limiting gluten intake has no effect on thyroid function. It is also worth noting that Hashimoto's disease often leads to many nutritional deficiencies, and an elimination diet can exacerbate them even more.

A diet devoid of gluten is becoming increasingly popular, but its rules are very restrictive. It consists of completely eliminating all products that may contain gluten. It typically involves completely avoiding grains such as wheat, barley, rye, and oats, as well as all their varieties and mixtures. According to the requirements of the European Commission regulation of 2009, products devoid of gluten must not be made from gluten-containing grains in which the total content of this protein exceeds 20 mg/kg of the product. In many cases, traditional grains are replaced by those that do not contain gluten, such as rice, amaranth, millet, buckwheat, and sorghum. However, a diet devoid of gluten, due to the elimination of a large group of products, can often lead to numerous nutrient deficiencies that are not health-promoting. The main nutrients that are lacking in a diet devoid of gluten are fiber and B-group vitamins, as well as folic acid, iron, and zinc. However, these deficiencies can be avoided by increasing the amount of buckwheat groats, millet, or brown rice in the diet. It is also important to include at least 5 portions of vegetables and fruits in the diet to increase the amount of minerals and vitamins. Unfortunately, most ready-made gluten-free products that can be found in stores are poor in nutritious and health-promoting ingredients. They provide more simple sugars, the excessive consumption of which can lead to obesity, type 2 diabetes, or tooth decay. A diet devoid of gluten, due to the elimination of many products, should be carried out under the supervision of a specialist to minimize the risk of deficiencies.

Despite the popularity of the gluten-free diet, there is a lack of research confirming its positive health effects in the absence of celiac disease, Dühring's disease, allergies, or intolerance. Using such a diet without a medical indication can be harmful to the body. Gluten-containing products, which often form the basis of the diet, are an excellent source of dietary fiber, B vitamins, and many essential minerals. Their complete elimination can lead to numerous nutritional deficiencies, which can negatively affect well-being and health. In the case of a necessary gluten-free diet, it is best to do so under the supervision of a specialist. There are also insufficient scientific evidence to confirm the need for gluten reduction in autoimmune diseases that do not coincide with intolerance to this protein. In the case of healthy individuals, introducing such a diet may negatively affect health and increase the risk of lipid profile disorders, digestive disorders, or the development of type 2 diabetes.