Everything you need to know about gluten

What is gluten

Gluten is a set of proteins, contained in cereal seeds, mainly wheat, but also barley and rye, as well as any of their varieties and hybrids (such as spelt, spelled, kamut, triticale and farro), and some varieties of oats.

Gluten is responsible for the elasticity in bread doughs and baked goods. The two main components of gluten are gliadin and glutenin.

Gluten is not essential for humans. It is a mixture of proteins of low nutritional and biological value, with low quality due to deficiencies in essential amino acids.

The gluten problem

Gluten is a somewhat indigestible protein. The reason is none other than our body does not have the necessary enzymes to fully digest it and it is precisely those small undigested pieces that can cause intestinal problems.

Healthy people do not notice discomfort when taking any of the cereals that contain gluten, at most a little discomfort that passes once the digestive process is complete. However, in other people, those small pieces of undigested gluten can cause autoimmune problems (celiac disease, gluten ataxia), allergies (such as respiratory, food or contact allergies) and sensitivity to this protein.

Below we describe the main pathologies that can be caused by gluten intake:

1. Celiac disease

It is an autoimmune disease characterized by a permanent and chronic intolerance to gluten. It is suffered by people who are genetically predisposed and is characterized by a lesion of the mucosa of the small intestine that causes atrophy of the intestinal villi. This atrophy produces an inadequate absorption of the nutrients from the food we eat (proteins, fats, carbohydrates, mineral salts and vitamins), with the consequent associated health problems.

Symptoms of celiac disease: chronic diarrhea, bloating, constipation, nausea and vomiting, anemia, generalized weakness, skin rashes, constipation, headache, tooth enamel changes, rickets, spontaneous fractures..

2. Gluten allergy

Gluten allergy is caused by an immediate hypersensitivity immune response.

Its mode of presentation is very diverse, from a simple rash around the mouth to severe anaphylactic shock. Unlike other conditions related to gluten, the symptoms of a gluten allergy start suddenly, within a few minutes of eating the food, and can quickly trigger a serious clinical situation.

Gluten allergy symptoms: vomiting, abdominal pain, diarrhea, digestive bleeding, asthma, cough, laryngitis, rhinitis, conjunctivitis, hives, edema or inflammation, atopic dermatitis, anaphylaxis reactions…

3. Gluten sensitivity

It is a newly diagnosed disease that is closely related to celiac disease. Patients with gluten sensitivity cannot be classified as intolerant or allergic, however this protein makes them sick. Its symptoms are very similar to those of celiac disease and it shares some with wheat allergy, so accurate diagnosis is essential.

Symptoms of gluten sensitivity: persistent pain in the abdominal area, frequent diarrhea, eczema or skin rash, headache, fatigue and confusion, constipation, nausea and vomiting, anemia, numbness or pain in the extremities, abdominal swelling.

4. Increased intestinal permeability

Gluten and certain intestinal bacteria are the two most powerful factors that cause an increase in intestinal permeability, regardless of genetic predisposition, that is, both in celiac and non-celiac patients. This increase in intestinal permeability causes substances that should not pass into the blood (toxins, chemicals, microorganisms and incompletely digested foods) and, depending on the person’s genetic predisposition, various health disorders can develop.

Currently, there is evidence that altered intestinal permeability is involved in the development of the following diseases:

• Autoimmune diseases, such as celiac disease, type 1 diabetes, rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel disease (Crohn’s disease), systemic lupus erythematosus, and primary sclerosing cholangitis.
• Cancers, such as glioma (brain or spinal cord cancer), breast cancer, lung adenocarcinoma, ovarian cancer, pancreatic cancer, prostate cancer, hepatocellular carcinoma (liver cancer) with infection by hepatitis C virus, acute non-lymphocytic leukemia, Fanconi anemia, diffuse large B-cell lymphoma and acute myeloid leukemia.
• Diseases of the nervous system, such as multiple sclerosis, schizophrenia, chronic inflammatory demyelinating polyradiculoneuropathy, and neuromyelitis optica.
• Inflammatory diseases.
• Infections.
• Allergies.
• Asthma.

5. Neurological disorders

Neurogluten is the term used to refer to the various neurological disorders caused by the consumption of gluten, that is, those that affect some organ or tissue of the nervous system. They can develop regardless of whether the person has digestive symptoms or intestinal injury, or whether the presence of antibodies in the blood. That is, both in celiac and non-celiac patients.

Gluten is capable of crossing both the intestinal barrier and the blood-brain barrier, as has been demonstrated in studies in rodents and by the presence of anti-transglutaminase 6 antibodies in the brain of people with gluten ataxia.

Gluten composition

Wheat gluten is made up of proteins called glutenins and gliadins (90%), lipids (8%), and carbohydrates (2%). Gliadin is the one that contains most of the products that are toxic to people with a genetic predisposition; Likewise, as already mentioned, it is responsible for causing an increase in intestinal permeability (involved in the development of autoimmune diseases, cancer, infections and allergies) regardless of genetic predisposition, that is, both in celiac and non-celiac patients. . Other cereals, due to their taxonomic proximity, contain homologous toxic peptides: barley (hordeins), rye (secalins), oats (avenins) and their varieties and hybrids, such as kamut and triticale. All of these proteins are collectively called gluten.

Modification of cereals over time

Throughout the 19th and 20th centuries, active genetic selection and direct genetic manipulation have greatly modified the original wheat varieties (Triticacee), from a few grains with low gluten content to large wheat crops highly enriched in gluten. ,​ with the aim of facilitating the preparation of the masses and obtaining attractive products for the consumer from the gastronomic point of view.​ The current criteria for the selection of wheat do not take into account its nutritional value, but its qualities from the point of view of functional view demanded by the food industry (determined by a high gluten content) and low economic cost.

Currently, gluten represents 80-90% of the total protein in wheat. This situation may have been the trigger for the large increase in the frequency of celiac disease, especially in populations whose genetic heritage derives from very ancient groups that did not successfully adapt to tolerate this protein.

Although when talking about “Gluten Free” we think of the total absence of gluten, with current detection methods it is impossible to prove a zero level of gluten in food. Consequently, the labeling “gluten-free” is not synonymous with “zero gluten”. In general, the laws allow up to 20 ppm, that is, 20 parts per million or 20 milligrams of gluten for each kilogram of product. This means that a minimum level of gluten contamination is present in the daily diet.

Classification of cereals and seeds by their gluten content

Now we tell you which are the grains that contain gluten and which are not. Spelled, kamut, and triticale are forms or hybrids of wheat. Flour from gluten-free grains must be certified gluten-free for consumption by people with celiac disease or those with non-celiac gluten sensitivity. It must be ground in mills that are independent of gluten-containing cereals, otherwise it would not be suitable, due to the presence of cross-contamination.

The main protein in rye gluten is secalin and that of barley is hordein, although both contain some gliadin. Rice itself does not contain gluten, but when it is processed or refined, substances that contain it are often added to it. Brown rice, which retains its shell and is not processed, has no gluten residues.

The types of grain that contain gluten are:

• Wheat: Contains the most common gluten and is found in many forms, such as whole wheat, wheat flour, wheat germ, and durum wheat. The gluten content in wheat varies, generally around 8% to 14% by weight.
• Barley: Barley contains gluten, although less than wheat. The gluten content in barley is approximately 5% to 9% of its weight.
• Rye: Rye also contains gluten, but at lower levels compared to wheat. The gluten content in rye is approximately 5% to 7% by weight.
• Spelled: Similar to wheat, spelt contains gluten, usually around 10% to 15% of its weight.
• Triticale: A hybrid between wheat and rye, triticale also contains gluten, with the content similar to that of wheat and rye.

It is important to note that these percentages are approximate and may vary depending on the variety and the growing process.

Grains that do not contain gluten are:

• Rice: Both white and brown rice are naturally gluten-free.
• Corn: Corn and its derivatives, such as corn flour and corn starch, do not contain gluten.
• Millet: An ancient grain that is gluten-free and used in certain cultures to make bread and other foods.
• Sorghum: Another gluten-free grain that is used in products as flour and as a whole grain.
• Amaranth: A pseudocereal that is naturally gluten-free and can be used as a whole grain or in flour.
• Quinoa: Another pseudocereal that does not contain gluten and is an excellent source of protein.
• Buckwheat: Despite its name, buckwheat is gluten-free. It is a pseudocereal that can be used in the form of whole grains or flour.

On the other hand, oats are naturally gluten-free, but are often grown and processed in facilities that also handle wheat, barley, and rye. This can lead to cross-contamination with gluten. Additionally, some people with celiac disease or non-celiac gluten sensitivity may react to oats due to the presence of a gluten-like protein called avenin.

External sources

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