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Food allergy
Last reviewed: 05.07.2025
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Food allergy is the name given to a food allergic reaction. To some extent, any person can not perceive a particular product and react to it with either irritable bowel syndrome or an allergy. Diagnosed and confirmed cases of food intolerance are still rare, since most often the food type is combined with other types of allergies.
In allergological practice, about 3% of cases of childhood food allergy and no more than 1% of adult allergic reactions to products are recorded. Such statistics show that this type of disease is often missed or not differentiated into a separate disease. Also, food allergy can have similar symptoms to food intolerance, which is not related to the immune system's response.
[ Why do food allergies occur?
Allergies to food products are most often provoked by absolutely benign products in people who have relatives or parents with allergies in their medical history. Any manifestation of the disease, be it hay fever or asthma, can be transmitted genetically and cause a reaction in descendants not to pollen, medications or insect bites, but to food products. The process of digesting food involves the production of a specific immunoglobulin - IgE, which, when released, begins to interact with basophil analogues - mast cells. These are labrocytes, mastocytes, which form the mechanism of adaptation of the immune system to unfamiliar substances that have entered the body. If the production of IgE is genetically determined as an aggressive response, the immunoglobulin automatically releases a mediator, a biogenic amine called histamine. Allergies to food products manifest their symptoms in the area, in the tissues where the histamine was released. If mast cells containing histamine accumulate in the nasopharynx, shortness of breath, itching, and possible swelling of the larynx appear.
If the release of the allergic response mediator occurs in the digestive tract, abdominal pain and bowel disorder (diarrhea) may occur. Histamine accumulated in the epidermis causes swelling.
What foods most often cause allergic reactions?
The leader in the list of "provocateurs" of food allergies are all seafood from shrimp to exotic lobsters. Second place is occupied by nuts, almost all types, but peanuts are especially dangerous, as they can cause instant anaphylactic shock. Also, an allergy to food can be provoked by sea fish or eggs. Children can have allergic reactions to milk, dairy products, this type of allergy, as a rule, goes away with age, since in the process of growing up, the digestive tract is formed, the immune system is strengthened and all adaptive mechanisms of the body are increased. If a person has already shown an allergy to pollen of flowering fruit trees, then most likely there will be an allergic response to the use of the fruit itself. Also, cross-allergy can be a reaction to ragweed and melon, to the flowering of birch, poplar and apple peel.
How does a food allergy develop?
Allergens are considered to be proteins that are completely harmless at first glance and are not subject to decay during heating during heat treatment of food. They penetrate the gastrointestinal tract, where they are also preserved, without being destroyed by acids and enzymes. In this “pristine” form, they enter the bloodstream, where they try to connect with “target” cells, the immune system recognizes them as foreign, and an allergic reaction develops. The onset of an immune response depends on the speed of digestion and the state of the gastrointestinal tract. As a rule, a food product that is a provocateur of an allergy to foods, getting into the oral cavity causes mild itching. The digestive process continues, except for itching, a person may not feel other alarming symptoms. As soon as the food is digested, a feeling of nausea begins to develop, pain in the abdomen appears, diarrhea is possible, blood pressure decreases. After a short period of time, allergens reach the skin with the bloodstream, a rash develops, often severe, up to manifestations of eczema. If the products of the histamine reaction penetrate the bronchopulmonary system, the patient may develop an asthma attack. The speed of development of the reaction from the initial mild itching to a bitterness or an attack of suffocation can fit into several minutes or several hours.
How are food allergies recognized?
If a person notices signs of a food allergy and consults a doctor, the doctor first collects anamnestic information to confirm or exclude a hereditary factor of allergy. Then it is necessary to describe the symptoms and manifestations of the allergy in as much detail as possible, make a list of products that are usually included in the diet. As a rule, a specific diagnostic method is prescribed to clarify the provoking food substance - a skin test. Literally a few drops of liquid containing the main component of a particular food are applied to the skin. A puncture is made in the skin, into which the liquid medium gets. After a certain time, a reaction in the form of a small edema should appear on the skin - this will be evidence of the presence of immune aggression to the introduced product. An immunoenzyme test and other analytical blood tests are also prescribed.
Treatment of food allergies
The most effective treatment, as well as prevention, is the complete exclusion of provoking products from the diet. It is necessary to be careful in compiling your own menu, study the composition of multi-component products, because they may contain an allergen, which even in microscopic doses can cause an allergy.
If the product somehow gets into the body and the reaction begins to develop, you should immediately take an antihistamine prescribed by a doctor. If the allergy attack intensifies and develops rapidly, you need to call an ambulance to prevent anaphylactic shock.
Food allergies are rarely isolated; as a rule, they recur, therefore, in order to avoid serious consequences of allergic reactions, you need to control your diet and always have a small personal first aid kit with you, containing all the necessary means to stop an attack of allergies.