Allergy to food
Last reviewed: 23.04.2024
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Allergy to food - the so-called food allergic reaction. To some extent, any person can not perceive a particular product and react to it either with irritable bowel syndrome or with an allergy. Diagnosed and confirmed cases of food intolerance are still a rare phenomenon, because most often the food species is associated with other types of allergies.
In allergological practice, about 3% of children's food allergies and not more than 1% of adult allergic reaction to food are recorded. Similar statistics show that basically this type of disease is often overlooked or not differentiated into a separate disease. Also, the food allergy may have a similar symptomatology with food intolerance, which is not related to the response from the immune system.
[Why is there an allergy to foods?
Allergy to foods is most often provoked by absolutely benign products from people with an anamnesis of relatives, parents - allergy sufferers. Any manifestation of the disease, whether it's hay fever or asthma, can be transmitted genetically and cause the offspring no longer to respond to pollen, medication or insect bites, but to food. The process of digestion of food involves the production of a specific immunoglobulin - IgE, which is released, begins interaction with analogues of basophils - mast cells. These are the labrocytes, mastocytes, which form the mechanism of adaptation of the immune system to unfamiliar substances that have got into the body. If IgE production is genetically determined as an aggressive response, immunoglobulin automatically releases a mediator, a biogenic amine called histamine. Allergy to foods manifests itself in the area in those tissues where the histamine release occurred. If mast cells containing histamine accumulate in the nasopharynx, dyspnea, itching, and possible laryngeal edema.
If the release of the mediator of allergic responses occurs in the digestive tract, abdominal pain, upset of the stool (diarrhea) may appear. Histamine, accumulated in the epidermis, provokes puffiness.
Which food most often causes an allergic reaction?
The leader in the list of "provocateurs" of food allergy are all seafood from shrimps, to exotic lobsters. The second place is occupied by nuts, almost all species, but peanuts are especially dangerous, since it can cause instant anaphylactic shock. Also, food allergies can be triggered by marine fish or eggs. At children allergic reactions can be on milk, dairy products, this kind of an allergy, as a rule, passes with the age as in the course of growing up there is a formation of a digestive tract, strengthening of immune system and increase of all adaptive mechanisms of an organism. If the person has already manifested an allergy to the pollen of flowering fruit trees, then most likely there will be an allergic response to the use of the fetus. Also, the cross-allergy may be in response to ragweed and melon, blossom of birch, poplar and apple peel.
How does the food allergy develop?
Allergens are considered to be completely harmless at first glance, proteins that are not prone to disintegration during the heating process during food heat treatment. They penetrate the gastrointestinal tract, where they are also preserved, not destroyed by the action of acids and enzymes. In such a "pristine" form they enter the bloodstream, where they try to connect with the target cells, the immune system recognizes them as alien, an allergic reaction develops. The timing of the onset of the immune response depends on the speed of digestion and the state of the gastrointestinal tract. Typically, a food product, which is a provoker of food allergies, getting into the mouth causes a slight itch. The digestive process continues, in addition to itching a person may not feel any other alarming symptoms. Once the food is digested, a feeling of nausea starts, a pain in the abdomen arises, diarrhea is possible, blood pressure decreases. After a short period, allergens with blood flow reach the skin, a rash develops, often strong, up to the manifestations of eczema. If the products of the histamine reaction penetrate the bronchopulmonary system, the patient may develop an asthma attack. The rate of development of the reaction from the initial mild itching to drinking or an attack of asthma can be kept within a few minutes or several hours.
How is the food allergy recognized?
If a person has noticed signs of food allergies and turned to a doctor, the doctor, first of all, collects anamnestic information to confirm or exclude a hereditary allergy factor. Then you need to talk as much as possible about the symptoms and manifestations of the allergy, make a list of foods that are usually included in the diet. As a rule, to specify the provoking food substance, a specific method of diagnosis is appointed - a skin test. On the skin is applied a few drops of liquid containing the main component of a food. In the skin a puncture is carried out, into which the liquid medium enters. After a certain time, a reaction in the form of a small edema should appear on the skin - this will be a testament to the presence of immune aggression on the injected product. Immunofermentogram and other analytical blood tests are also prescribed.
Treatment of allergies to foods
The most effective treatment, as well as prevention, is the complete elimination of provoking products from the diet. It is necessary to be careful in drawing up your own menu, to study the composition of multicomponent products, because they can contain an allergen, which even in microscopic doses can cause allergy.
If the product, somehow gets into the body and the reaction begins to develop, you should immediately take an antihistamine drug prescribed by your doctor. If the attack of allergy increases and rapidly develops, you need to call an ambulance to prevent anaphylactic shock.
Allergy to food is rarely single, as a rule, it recurs, so to avoid serious consequences of allergic reactions, you need to monitor your diet and always have a small personal first aid kit containing all the necessary drugs that stop the attack of allergy.