Histamine is a molecule present in certain foods, but above all naturally produced by the body and involved in immune reactions. Usually well regulated, it can accumulate in some people and cause a series of symptoms, causing what is known as histamine intolerance.
Definition: what is histamine?
Histamine is a molecule naturally produced by the bodywhich plays several important roles. She is best known for her involvement in allergic reactionsbut it also intervenes in digestion, the nervous system and the regulation of sleep.
Concretely, it is stored in certain cells of the immune system, then released when needed. During an allergic reaction, it is released in large quantities and causes well-known symptoms: itching, runny nose, redness, swelling. It acts as a sort of chemical messenger, responsible for triggering a defense reaction.
But histamine is not only produced by the body, since it is also present in certain foodsin particular fermented, matured or poorly preserved (cheese, cold meats, wine, etc.).
Histamine reaction: intolerance or allergy?
Since histamine is directly involved in the phenomenon of allergic reactions, it is often wrongly believed that it is itself responsible for allergic reactions.
However, the mechanism in play is totally different. In an allergy, the immune system overreacts to a normally harmless substance (pollen, food, etc.), by producing specific antibodies. This reaction then triggers a massive release of histamine, responsible for the symptoms.
In histamine intolerance, on the other hand, the problem does not come from an immune reaction, but from a lack of regulation.
Hence the frequent confusion with allergy.
What are the symptoms of this intolerance?
The symptoms of histamine intolerance can be confusing, because they are very varied and not very specific, which explains why it is difficult to diagnoser and probably underestimated.
“The reactions are mostly skinsuch as redness, flushing, itching, rash or hives. To this can be added a runny nose and itchy eyes” describes the allergist.
But intolerance can also manifest itself through digestive symptoms such as bloatingof the abdominal painof the diarrhea or nausea. Some people also describe headaches, even migraines, as well as unusual fatigue. Finally, histamine can act on blood vessels and the nervous system, it can also cause palpitations or a slight drop in blood pressure.
THE time to onset of symptoms is also quite variable. In some patients, the reaction is rapid, almost immediate after ingestion of foods rich in histamine, and in others it can be more delayed and appear several hours after the meal, which further complicates its diagnosis.
From what age can it manifest?
It generally results from a progressive imbalance that develops over time. Different factors can, for example, alter the body’s ability to break down histamine: a reduction in the activity of the enzyme diamine oxidase (DAO), digestive disorders, certain illnesses, medications or even hormonal changes.
In children, these mechanisms are much rarer which explains why symptoms suggestive of histamine intolerance generally first point towards other diagnoses of food allergies or intolerances.
Cheese, cold meats, smoked fish, wine: what foods rich in histamine should be avoided in case of intolerance?
Foods rich in histamine are essentially those which have undergone a transformation, fermentation or aging. For example, we find the aged cheeses (comté, roquefort, parmesan), cold meatsfish that have been smoked or have been poorly preserved, as well as certain fermented products like the sauerkrautfermented soy or vinegar. Alcoholic beverages, especially wine and beer, also contain it. Generally speaking, the more a food is processed or “aged”more Histamine content increases.
Not because they are naturally very rich in histamine, but because they can accumulate quickly if they are not perfectly fresh. Poor storage, even brief, is enough to increase their content, which explains why they are frequently involved.
Chocolate, tomatoes, strawberries, kiwi, avocados: what are histamino-liberating foods?
In addition to foods rich in histamine, others which contain very little, on the other hand promote its release by the body. This is particularly the case of chocolatecitrus fruits, strawberries or tomatoes, which can therefore cause a reaction despite their low histamine content.
“Whether the foods are rich in histamine or histamino-liberators: the result remains the same in sensitive people” adds our expert.
Alcohol can be involved in two different ways in histamine intolerance:
On the one hand, some fermented or aged alcoholic beverageslike wine, beer or spirits contain histamine directly and can therefore trigger a reaction. On the other hand, alcohol inhibits the histamine-degrading enzyme (DAO) in the body. Even a drink containing little histamine can cause a buildup in the body if DAO is blocked. This combination explains why some patients experience particularly strong reactions after just a glass of red wine.