Definition
Tomato allergy is characterized by an exuberant reaction of the immune system to the consumption of tomatoes. However, individuals are unlikely to be allergic to the tomato itself. Rather, the tomato contains histamine, which plays an important role for the immune system in allergies. Affected persons usually have an intolerance to histamine, which acts like a tomato allergy. The histamine causes the release of various immune substances, which trigger the typical symptoms such as itching, burning on the tongue, nausea, vomiting and diarrhoea.
These are the symptoms of an allergy to tomatoes
The symptoms of an allergy to tomatoes always appear at a certain time interval after consumption of the tomatoes. The symptoms include gastrointestinal symptoms such as nausea, vomiting, abdominal pain and diarrhoea. In more severe allergies, the mouth and throat area may also be affected.
There, a burning or itching sensation develops on the mucous membranes and tongue. Redness and swelling are also possible. An extended allergic reaction also includes a skin rash, which is usually located near the area of contact with the tomato (i.e. in the face, especially around the mouth).
When eating tomatoes, the tongue comes into direct contact with the allergen. This is why the symptoms can be particularly severe there. These include a burning and itching sensation on the tongue.
Redness and even small blisters can also be a sign of a tomato allergy. In severe cases, the tongue swells up considerably on contact with tomatoes, which can lead to breathing problems. If the swelling is so severe that the throat is also affected, it can even lead to life-threatening shortness of breath.
When in contact with tomatoes, the immune system of allergy sufferers reacts more strongly to substances that are actually harmless. The body interprets the tomato or its ingredients as a dangerous substance and therefore tries to fight it. This process leads to an increased release of immune cells and signal substances, which put the body on alert.
These released substances are distributed as quickly as possible in the body so that an optimal defense against the tomato classified as dangerous can take place. These well-distributed substances irritate the nerve endings and thereby trigger itching. Besides nausea, vomiting, flatulence and abdominal pain, diarrhoea is one of the symptoms of the gastro-intestinal tract, which is particularly common in allergies to food.
In the intestine, the food is usually broken down into its individual components and then absorbed into the blood. Due to the strong comminution, the body has contact with the ingredients of the tomato in many places and inevitably also with the histamine, to which the immune system reacts more strongly. The aim of this allergic reaction is, among other things, the rapid removal of the tomato from the intestine.
Such removal is possible very quickly with the help of diarrhea, which is why the body uses diarrhea as an effective defense strategy. The eyes are not typically affected by a tomato allergy. They are more likely to react in the case of a cross-allergy, i.e. when a person is allergic to birch pollen, for example.
Because of the chemical similarity of the substances, there is also an allergic reaction to the tomato. This can manifest itself through a constantly running nose, which in turn affects the eyes. Nevertheless, the typical allergic symptoms like burning or itching of the eyes, in addition redness and swelling are rather rare in tomato allergies.