In a world designed to provide humans with food and energy, the simplest things we eat may sometimes turn into a source of real danger. The reason is not due to a change in the nature of the food itself, but rather to a defect in the way the immune system deals with it. It sometimes misidentifies safe food ingredients, classifies them as harmful foreign bodies, and launches an exaggerated defensive response towards them.
This imbalance may lead to reactions that vary in severity from one person to another, starting with mild symptoms such as itching and digestive disorders, and in some cases they may lead to serious, life-threatening complications, even though the substance ingested is completely safe for most people.
What is a food allergy?
Normally, the immune system recognizes the food without showing any reaction. But in cases of food allergy, the immune system considers ordinary proteins – such as those found in milk or peanuts – a real threat, and launches a strong defense response to confront them.
Thus, the problem does not lie in the food itself, but rather in an immune system that overreacts and treats natural ingredients as if they are an imminent danger.
How does the body react to allergies?
When you eat a food that causes an allergy, your body may begin to produce antibodies known as immunoglobulin (IgE). These objects are linked to specific immune cells, and when exposed again to the same substance, these cells are stimulated to secrete chemicals, most notably histamine.
Histamine is directly responsible for allergic symptoms, such as itching, rash, swelling, shortness of breath, and other signs that may appear quickly or within a short time.
Who is most vulnerable to infection?
Studies indicate that some groups are more susceptible to developing food allergies, including:
- Young children: Allergies often appear before the age of three, especially to milk, eggs, peanuts, and tree nuts.
- Genetic factor: Having a family history of allergies increases the possibility of infection, as a result of an inherited tendency to produce IgE towards certain foods.
- Associated allergic diseases: such as eczema and asthma, as the immune system is more sensitive and ready to react.
- Environmental factors: such as feeding pattern in the early stages, type of breastfeeding, and early exposure to various irritants.
- Lack of exposure to beneficial microbes: This is known as the “hygiene hypothesis,” where excessive sterilization may lead to poor training of the immune system.
Types of allergies
Food allergies are divided into two main types:
1. IgE-based allergy
It is the most common and dangerous, and is characterized by the rapid onset of symptoms, which may include a skin rash, itching, swelling of the lips or face, difficulty breathing, dizziness or loss of consciousness in severe cases. These symptoms may develop into an allergic shock known as anaphylaxis.
2. Allergy that does not depend on IgE
It is less dangerous, and often affects the digestive system, and its symptoms are vomiting, diarrhea, and abdominal pain. It is characterized by its late onset and longer duration, and rarely poses a direct threat to life.
Anaphylaxis…the most dangerous form of food allergy
In some cases, a very small amount of food – and even inhaling its traces – is enough to trigger a severe allergic reaction that may lead to “anaphylaxis,” a life-threatening medical emergency.
Anaphylaxis is the most dangerous form of allergy, as it causes a rapid and severe reaction that requires immediate medical intervention. Its most prominent signs are: difficulty breathing, swelling of the face or throat, a rash or severe itching, in addition to dizziness or loss of consciousness.
What is IgE?
Immunoglobulin (IgE) is a special type of antibody that acts as a sentinel for the immune system, detecting potential dangers and triggering a defense response.
But in cases of allergies, this “guardian” makes a mistake, treating natural substances as a threat, and a series of rapid reactions occur within the body. Measurements of IgE in the blood help doctors diagnose this disorder and monitor the severity of the allergic response.
How is a food allergy diagnosed?
The diagnosis of food allergy depends on a set of integrated steps, the most prominent of which are:
- Take a careful medical history, and analyze the timing and severity of symptoms.
- Conduct skin tests to identify potential allergens.
- Medically supervised food challenge tests, in which the patient is given increasingly small amounts of the questionable food and monitored for any allergic symptoms.
- Blood tests to measure IgE levels associated with allergies.
Treatment…prevention first
Food allergy treatment is mainly based on prevention, by carefully avoiding the allergenic foods and carefully reading the ingredients of food products.
When an allergic reaction occurs, antihistamines can be used to relieve mild symptoms, such as itching or rash, while severe cases require urgent intervention with an adrenaline injection, which may save a life.
Treatment is not limited to medications, but also includes educating the patient and those around him on how to deal with emergency situations, and paying attention to the possibility of transmission of allergens during food preparation.
Most allergenic foods
Although any type of food may cause an allergy, most cases are linked to specific foods, most notably: milk, eggs, peanuts, tree nuts, fish, and wheat.
Some additives, such as sulfite used in preserving foods and drinks, may also lead to symptoms resembling allergic reactions in some people.
Are all allergies caused by food?
Not necessarily; Allergy-like reactions may occur due to taking certain medications, insect stings, or even while exercising, and in some cases the exact cause is not known.