Food allergies: why and who gets it and can it be cured
STATISTICS OF FOOD ALLERGY MANIFESTATIONS
Up to 6% of children under five and about 3-4% of adults have food allergies. In the US alone, 200,000 people a year require emergency medical care due to allergic reactions. The total number of people with allergies in this country reaches 32 million, of which 5.6 million are children under 18 years of age. There are no clear statistics on food allergies in Ukraine, however, doctors are unanimous: our country keeps pace with global trends and the number of people with this disease in Ukraine has also increased dramatically in recent decades.
In particular, from 1997 to 2011, the prevalence of food allergies in children increased by 50%. This disease has, on average, two students in a school class. And approximately 40% of children with food allergies are sensitive to more than one food. The same number of children are exposed to a severe form of an allergic reaction – anaphylaxis.
Between 2007 and 2016, there was a 380% increase in medical procedures to treat anaphylaxis in those same states. At the same time, about 20-25% of epinephrine, which was used in schools, was administered in cases where the presence of an allergy was not known until the time of the reaction.
ALTHOUGH MOST FOOD ALLERGIES APPEAR IN CHILDHOOD, IN AT LEAST 15% OF PATIENTS THIS PROBLEM IS FIRST DETECTED BY ADULT AGE.
CAUSES OF FOOD ALLERGIES
A food allergy occurs when the immune system identifies proteins in food as foreign and attacks the antibodies produced in response to them in our bodies. Just as it happens when detecting microbes and bacteria. The body releases several chemical mediators, such as histamine, which lead to allergy symptoms. Most food allergies are caused by immunoglobulins E ( IgE ).
The significant increase in the number of people with sensitivity to various products, which has been observed in the past few decades, can be explained by significant changes in the diet of the population. Another version says that everything is to blame for “excessive” sterility, and, as a result, the lack of early exposure to microbes necessary for the proper development of the child.
In addition, it was previously recommended to protect children from early exposure to allergens, but despite this, the number of cases of allergies was growing. Now, on the contrary, it is believed that the early introduction of potential allergens into the diet, as early as six months of age, can prevent food allergies. Such an association, for example, has been shown for peanut reactions in children with egg allergies and eczema.
EXACTLY CHILDREN IN WHICH AT AN EARLY AGE ATOPIC DERMATITIS (ECZEMA) IS DETECTED, THERE IS MORE RISK OF BUYING AND FOOD ALLERGY.
Conversely, children with the latter are two to four times more likely to develop asthma or eczema. In turn, the combination of food allergies, asthma and/or eczema increases the likelihood of developing severe allergic reactions.
In addition, there are foods that are more allergenic in themselves. So, 90% of all food reactions are due to only 8 types of products. They are called the big eight food allergens. it:
Major food allergens:
- A fish
WHEN CHILDREN REACTION TO EGGS AND MILK, WHEN ADULT REACTIONS TO FRUITS AND VEGETABLES ARE MORE MORE COMMON.
Allergies to nuts, peanuts, fish and shellfish occur regardless of age and often persist for life. Whereas sensitivity to milk, eggs, soy, and wheat can go up to age five or early school age.
Allergies can also be caused by various food additives, such as sulfite or benzoic acids and food allergens found in mustard and sesame. But garlic and coriander rarely provoke allergy symptoms. Even less often, meat and gelatin cause allergies.
The EU has clear labeling requirements for products that can cause allergies. In addition to the G8 allergens already mentioned above, celery, gluten-containing cereals (including wheat, rye, barley and oats – although oats do not contain gluten by themselves, they are often contaminated with other grains) and lupine (used to make gluten-free flour).
FOOD ALLERGIES AND SYMPTOMS
Depending on the symptoms and the period of its occurrence, food allergies are divided into three types.
IgE -mediated reaction . It causes the immune system to produce antibodies called immunoglobulin E ( IgE ). In this case, a severe reaction to the food in the form of anaphylaxis is more likely, and symptoms occur within seconds or minutes after eating the product.
IgE -mediated reaction . Its symptoms can develop much longer (up to several hours), which causes certain difficulties with diagnosis.
In addition, some people may experience symptoms of both types.
Separately allocated oral allergic syndrome (syndrome “pollen-food” or oral allergy syndrome). It is caused by the similarity of proteins in pollen and certain fruits, nuts, or vegetables. Signs of this condition are usually itching in the mouth and throat, sometimes with slight swelling, immediately after consuming the product. Often, peeling or cooking the fruit or vegetable is enough to avoid symptoms.
In general, the common symptoms of a food allergy include the following:
- A skin rash (urticaria) that can bulge out of the skin and itch a lot. Angioedema or swelling of the eyes, lips, mouth, throat, palate, tongue, and face.
- · Spasm of the throat and difficulty breathing.
- Swelling of the larynx, which can lead to hoarseness and subsequent breathing complications from coughing to hoarseness
- Nausea, vomiting, and diarrhea, as well as bloating, pain, and abdominal cramps, mucus, or blood in the stool
- Flu-like symptoms, including runny nose, nasal congestion, sneezing, red eyes (allergic conjunctivitis).
- · Dizziness
- · A little later, eczema may appear, which leads to the formation of itchy, dry cracks in the skin.
- Children with food allergies (especially to milk proteins) often cry because of colic and intestinal cramps. The child may have diarrhea, and there is usually redness or a rash around the ear and genitals.
DIAGNOSTICS OF FOOD ALLERGY
Various methods are used to diagnose allergies. Your doctor may ask you to keep a food diary that describes what you eat, the severity of your symptoms and how long they last, and ask about your family history of allergies. If we are talking about a child, it is noted what kind of feeding and was / is, because in children who are breastfed, food allergies develop less often.
elimination diet may be recommended : a product suspected of a reaction is removed from the menu for 2-6 weeks, after which it is gradually reintroduced into the diet. In addition, people with IgE -mediated food allergies are advised to have a skin test or blood test to detect antibodies to specific antigens.
TREATMENT OF FOOD ALLERGIES
Antihistamines are commonly used to treat mild to moderate allergy symptoms. Some of them, mainly the first generation, cause drowsiness, so driving should be avoided while taking them.
However, in severe cases, when anaphylaxis develops, no antihistamine will be effective.
Today, drugs have begun to appear that, such as immunotherapy for pollen or household allergies, are designed to develop tolerance to peanuts over time. But such remedies cannot yet completely get rid of allergies and allow you to safely eat dangerous food.
One of these drugs, approved in the United States at the end of January 2020, is available in capsules and is approved for children aged 4 to 17 years. The first dose is given in the doctor’s office. Further, the doctor will need to be consulted each time the dose is increased (every two weeks) until the maximum dose is reached after about six months.
Children taking these medications will still need to wear an epinephrine dispenser and avoid contact with peanut products. But perhaps such a pill can soften the reaction from inadvertent ingestion of the allergen. Studies have shown that some of the subjects who did not stop taking the drug, after a year, were able to eat about two peanut kernels at a time.
Oral drugs are also being developed to treat allergies to eggs, walnuts, cashews and hazelnuts, as well as body patches to develop tolerance to peanuts, milk and eggs.