Research Assistant - Fırat University, Faculty of Health Sciences, Department of Dietetics
"A gluten-free diet may not be suitable for healthy individuals"
What is gluten?
Gluten is a high molecular weight protein commonly found in grains such as wheat, barley, and rye. Gluten is a compound protein made up of glutenins and prolamins and is also responsible for wheat's ability to form dough. Therefore, gluten is an integral component of an extensive variety of wheat-containing foods, including bread, cereals, and pasta. The viscoelasticity of wheat-based doughs is the key feature that gives this grain an advantage. This property of gluten is used not only in dough production but also as an additive in various foods in the industry.
What is a gluten-free diet?
A gluten-free diet can be defined as a diet in which wheat, barley, rye and products derived from these grains are not consumed. In 2013, the United States Food and Drug Administration defined "Gluten-free food" as foods containing <20 ppm or less than 20 mg/kg gluten. In a gluten-free diet, corn, rice and tapioca, buckwheat, quinoa, amaranth and tef, sorghum and millet, chia seeds and flax seeds, polenta, and potentially gluten-free grains and grain products can be used as alternatives to gluten-containing grains.
In which diseases should a gluten-free diet be followed?
Gluten-related disorders are defined as celiac disease (CD), wheat allergy (WA), and non-celiac gluten sensitivity. Today, a "gluten-free diet" is generally viewed as a healthy lifestyle choice rather than a dietary treatment that is appropriate and necessary for a specific condition such as CD. Gluten-free products are used in the nutrition of individuals diagnosed with celiac disease or those with gluten intolerance. The only known treatment method for celiac disease and non-celiac gluten sensitivity is a lifelong gluten-free diet. When individuals with celiac disease consume gluten, an inflammatory process targeting the intestinal mucosa is triggered, resulting in immune-mediated enteropathy, which can have symptoms such as malabsorption, diarrhea, steatorrhea, weight loss, or growth failure. Celiac disease; It is a chronic intestinal inflammation associated with immune and genetic factors, in which sensitivity to gluten in wheat, rye, barley and oats is observed. It is very important for these individuals to stick to the diet in order to improve their health and increase their quality of life.
Situations where a gluten-free diet is used as a treatment
Gluten-free diets are also applied in some diseases and disorders such as irritable bowel syndrome (IBS), autism spectrum disorder (ASD), rheumatoid arthritis (RA), schizophrenia, fibromyalgia and endometriosis.
In a meta-analysis study examining nine controlled studies; it was stated that a gluten-free diet is not proven enough to be recommended routinely for IBS patients.
A gluten-free and casein-free diet (GFCF) intervention is usually performed in patients with ASD. In a review examined, although the underlying cause of the gastrointestinal symptoms frequently seen in individuals with ASD is not fully known, the most widely accepted is the opioid theory. It was stated that the GFCF diet has a beneficial effect in support of the opioid theory. Since the studies are usually applied to a small number of individuals and for short periods of time, it was concluded that the effect of this diet on autistic behavior is not clear.
Gluten is thought to be an immunological trigger for rheumatoid arthritis. However, the question of which RA patients can benefit from a gluten-free diet remains.
The identification of a link between wheat gluten consumption and schizophrenia symptoms has raised the question of whether a gluten-free diet can be applied to schizophrenia patients. In order for schizophrenia patients to benefit effectively, more research is needed to examine biomarkers of gluten sensitivity and inflammation.
The presence of gastrointestinal symptoms such as nausea, abdominal pain, chronic fatigue, chronic pain and mood disorders, which are frequently seen among various disorders associated with gluten in fibromyalgia patients, has led to the investigation of a gluten-free diet for these patients. As a result of the studies, it has been emphasized that more research is needed to fully explain the relationship between gluten-free diet and fibromyalgia.
Endometriosis, whose etiology is still largely unknown, is known to be a multifactorial disease. Although research on the relationship between endometriosis and a gluten-free diet is limited, some findings suggest that a gluten-free diet may alleviate endometriosis symptoms. More research is needed on the effects of a gluten-free diet on endometriosis.
Popularity of a gluten-free diet
Recently, the gluten-free diet has gained popularity as a dietary choice among healthy individuals. In addition to its use for managing gluten-related disorders, many adopt this diet to control body weight or alleviate gastrointestinal symptoms, including bloating and cramping.
Advantages of a gluten-free diet
For individuals with celiac disease, adhering to a gluten-free diet remains the sole therapeutic option. In genetically susceptible individuals, the consumption of gluten triggers a T-cell-mediated immune response, resulting in villous atrophy and associated clinical manifestations. By eliminating gluten from their diet, these individuals can prevent the immune reaction, making a gluten-free diet essential for their health and well-being.
Disadvantages of a gluten-free diet
High Cost and Inconvenience: Many studies have demonstrated that adherence to a GFD significantly increases the cost of food for adherents, with prices 2 to 3 times greater than for similar nongluten-free products. Aside from the higher cost, individuals following a gluten-free diet (GFD) face a more limited selection of foods and may struggle with both finding appropriate options and maintaining strict adherence to the diet.
Nutritional Risks. GFD can lead to nutritional deficiencies of macronutrients and micronutrients. Compared to their wheat-based counterparts, gluten-free products show deficiencies in minerals, including calcium, iron, magnesium, and zinc, and in vitamins, including vitamin B12, folate, and vitamin D, as well as significantly reduced fiber. Gluten-free products are typically not enriched or fortified and are frequently made from refined flour or starches. They do not have the nutrient content found in their gluten-containing counterparts.
Gluten-free foods made from cereals tend to have a high content of carbohydrates and fats, but they often lack certain micronutrients. Studies have indicated that these products may lead to insufficient intake of fiber, as well as vitamins and minerals such as thiamin, folate, niacin, riboflavin, calcium, magnesium, iron, and zinc. A gluten-free diet can elevate dietary exposure to arsenic, while meals on this diet often contain more hydrogenated and saturated fats, as well as having a higher glycemic index.
Conclusion
In general, it is stated that a gluten-free diet is a less healthy dietary option than a normal diet for those who do not have celiac disease. For these reasons, a gluten-free diet should not be adopted for weight loss or general health improvement unless a gluten-related condition is diagnosed by a physician. If such a medical condition (e.g., celiac disease, gluten sensitivity, or allergy) is present, the diet should be followed under the guidance of a dietitian with expertise in this area to avoid deficiencies in both macro- and micronutrients.
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