Food intolerance or allergy?Pseudo-allergic reactions
Food intolerance or allergy?
Since a “simple” food intolerance can cause some typical symptoms of food allergies – such as nausea , vomiting , diarrhea and abdominal cramps – many people tend to confuse the two terms. In reality, food intolerances , unlike allergies, are always linked to a dose, which each individual should know to avoid exceeding it. Another fundamental difference is that the immune system is never involved in food intolerance, even if in many cases the symptomatology, in some respects superimposable to that of allergies, suggests the opposite.
In most cases, food intolerance is linked to enzymatic dysfunctions, therefore to the deficiency or lack of enzymes necessary to digest certain substances; particularly known is the deficiency of lactase , a protein necessary for the digestion of milk sugar and whose deficiency leads to the widespread intolerance to lactose .
Differences between Allergies, food intolerances and pseudo-allergic reactions |
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| Food allergy *:
symptomatology triggered within a few minutes of taking a certain food or group of foods (from 2-3 ‘to 30-120’), sometimes even in a violent way. Food allergy is immunologically mediated and symptoms are triggered by the intake of even small amounts of the responsible food. |
Food intolerance:
symptomatology linked to the quantity of the food taken and determined by particular molecules present in the food or by dysfunctions of the digestive system (enzymatic deficiencies). Symptoms often overlap with those of allergy but differ from them because they do not involve the immune system and have a late onset, sometimes even after a few days of taking. Examples are lactose intolerance and favism . |
Pseudo-allergic reactions:
they are given by foods rich in histamine and / or tyramine or containing histamine liberating substances. Taken in large quantities, they can cause symptoms similar to those of an allergy. |
| (*) The terms food allergy and food hypersensitivity can be used interchangeably | ||
Pseudo-allergic reactions
Pseudo-allergic reactions have all the characteristics of allergies, except the involvement of the immune system. They are caused by foods that are themselves rich in tyramine or histamine, or capable of stimulating the body’s release of histamine. The release of these chemical mediators represents the final point of the cascade of allergic reactions and is responsible for the typical manifestations at the cutaneous, respiratory, gastrointestinal level, etc. Strawberry
intolerance belongs to the category of pseudo-allergic reactions, because this food, similar to tomatoes and shellfish, stimulates the release of histamine. Once ingested, these foods, although devoid of allergenic power, can mimic an allergic reaction from a symptomatic point of view. These manifestations are controlled by antihistamine therapy and do not cause concrete dangers for the health of the individual (which are instead typical of a real food allergy).
By consuming this type of food, skin rashes (red spots on the skin , itching ) may appear but, once the administration is stopped, the symptoms quickly subside. The quantities capable of triggering the allergic reaction vary from person to person in relation to the individual predisposition.
| Foods rich in histamine and / or tyramine: fermented cheeses, aged cheeses , pork liver , sausages , blue fish ( sardines , mackerel , anchovies ), tuna , salmon , herring, tomatoes, spinach , fermented drinks. It should be noted that the concentration of histamine and tyramine is inversely proportional to the state of freshness of the fish (when a few days old fish is consumed it is easier to run into unpleasant pseudo-allergic problems). |
