Allergy is one Special sensitivity of some people who let them respond in an exaggerated way To one or more external elements.
One of the most common causes of allergy are; Plants of plants, some foods, chemicals (including some medicines), fungi, dust mites, insect bites and In general, any substance can activate a reaction of the body’s immune system.
This peculiarity of allergic people to develop an exaggerated response to an external agent (allergen) is accompanied by a series of Physical and chemical reactions responsible for the symptoms of allergy.
Allergies
Almost one in four Spaniards suffers from some allergyAccording to the Spanish society of allergology and clinical immunology (Seaic). The share is double that 30 years ago, although half of what will be 25 within.
This trend to grow It is worldwide: The World Health Organization predicts that in 2050 one in two people will be allergic. Many of these disorders are breaths and their increase is related to environmental factors such as climate change. But what reasons explain that others also shoot allergies, as the Food?
What are food allergies?
The allergies The most common foods include the calls’Great nine ‘: Egg, milk, peanuts, nuts, seafood, fish, wheat, soybeans and sesame. These diseases are a reason for great concern, especially with parents of allergic children, because even very small quantities of these foods can cause a serious reaction –anaphylaxis or anaphylactic shock – that requires injections of Epinephrine.
Moreover, experts clarify that the degree of an allergic reaction to a food is not predictable, even for the same person: A serious response to a concrete allergen on one occasion does not mean that the intensity will be equal, bigger or less the next time. Those allergic people forces always to be on the worst.
Seaic collects that allergies Food affects 5 % of adult Spaniards and 7-8 % of children, but figures in different countries suffer from variations, depending on the criterion used, under less than 1 and more than 10 %. Based on extensive health files to try to obtain more precise data, A recent study in England calculates 4 % of children younger than five, 2.4 % of older children and 0.7 % of adults.
Allergy or intolerance?
One of the reasons for the broad fork in the figures is that the Own patients tend to confuse with allergies, which are food intolerances. The first are incorrect immune reactions, which take a harmless protein from a food by a dangerous attacker. This false defensive response produces a kind of antibodies called Ige that activate manure cells and basophils that produce cells from histamine.
Bee allergies common foods join more rare, such as the syndrome of allergy oral, a cross reaction of the allergy at the pollen With certain foods. Another but more frequent case is intolerances, where there is no immune response, but an inability to process one Nutrientthat can cause different symptoms. And a more complex situation is the disease Celiacin which an intolerance for gluten It induces an abnormal reaction that causes auto immunity, a reaction to the organism itself.
The distinction between allergies and intolerances is one of the confusion More typically around these ailments, of which there are countless doubts, also for science. It is known that the children’s population is the most affected and that some allergies Asked the tendency to steer with age, especially milk, egg or soy; Something that usually does not happen for other allergens such as peanuts, nuts or seafood.
How do allergies appear?
There is no one cause defined for these diseases. It is not known how they occur or why they are disappearing, or what gives us to develop our age adult A allergy To a food that we have consumed. There is no way to prevent allergies That is why there is no immediate explanation for the increase in allergies Food, which is more than double in the English study mentioned in just 10 years, from 2008 to 2018; And even less for the fact that the share of allergies has been stabilized since 2018.
“Many factors can have an impact,” he says sin Ruchi GuptaDirector of the Center for Food Allergy & Asthma Research of Northwestern University. Certain indications tend to receive the approval of the scientific community: decades support the proof of evidence for decades Microorganisms From the area. Data published in 1989 by epidemiologist David Strachan led to indicating this idea as ‘hygiene hypothesis’.
The name was ambiguous, which implies that cleaning is harmful or that children’s infections are favorable. Scientists explain that this is not the point, but that trying to raise children in a bubble of sterility It does not protect them as their parents believe. “A completely empty world of microbes can lead to serious changes Immune And endocrine, because our body expects it to see microbes in the environment, ”says the microbiologist Jack Gilbertfrom the University of California in San Diego.
What to do with allergenic foods and children?
A more refined and current version of this hypothesis is called ‘old friends‘, and specifically refers to the microbes who have lived and merged with us for millions of years. It would be this Microbiome Ancestral person who helps to train our immunity. According to the microbiologist Erica Hartmannfrom Northwestern University, “It is not yet clear what to be exposed and whenBut a lack of exposure to microbes is linked to diseases Car -immuun And Allergies.
And in the same way, which is not sterile, it does not protect children from the most allergenic foods. allergies, As used to be believed before evidence was shown otherwise: introduce food such as such as Peanut or egg as quickly as possible reduces the risk of allergies. In the United Kingdom these essays were published in 2015-16, and therefore the authors of the quoted English study increase the possibility that the change in official recommendations are increasing the stagnation from the allergies In recent years.
It is interesting that if the consumption of allergen food protects against allergies, Instead, the Exposure to them through skin or respiratory tract Before it is brought to the diet, it produces the opposite effect. This hypothesis called ‘Dual exposure‘, who has won credit in recent years and for which Potosimile Immunological Mechanisms have been presentedadvises the introduction of these foods in the diet for contact airways or skin With your allergens you can have the appearance of one allergy.
Which other factors prefer allergies?
All the above does not close the matter of the origin of the allergy And his growth. As the medical historian notes Matthew Smith” Author of the book Another poison: a history of food allergy“The truth is that we still don’t know what the epidemic of allergy to the peanut or the increase in rates of allergies food “.
Under the possible additional factors, inheritance discourse geneticsthe lack of vitamin D, the abuse of antibiotics and other interventions that the Digestive microbiotaBecause this is attributed Protective paper against allergies through the barrier of the intestinal epithelium. But scientists are still investigating which other aspects of our lifestyle They can allergies And food intolerances, and why certain regions, such as Australia, are particularly sensitive.
Is there a remedy or treatment?
There is none healing For the allergies The most obvious basic measure for allergic or intolerant is to prevent dangerous food. In the case of allergies, who hold a greater risk because of the possibility of a Anaphylactic shockhave car -injectors or epinephrine -pencils -the calls Epipenen– You can save lives.
Treatments are currently being rehearsed by oral immunotherapy (ILO, for his acronym in English), consisting of introducing increasing quantities of allergens in the diet under medical supervision for sensitive The immune system.
There is a medication specifically directed against the allergy On the peanut: Palforzia, which contains allergen and is authorized in various countries, including Spain. Experts still discuss the balance between the benefits and the risk of the ILO.
Another approach is the use of antibodies who neutralize the IGE of the allergic reaction. One of them, called Omalizumab and marketed as Xolair, has been used since the beginning of this century. An assessment of 2025 has analyzed the essays that have combined these antibodies with the IAO: “The omalizumab facilitates rapid and efficient desensitization in the allergy Pediatric food, which improves the safety of this Combined therapy“, Concluding the authors, who recommend more research to take advantage of their possible benefits.
“It’s an interesting time for allergies eat because we have new treatments In the market, “Gupta values.” They are not priests, but they really help to increase the threshold. “The pediatrician and researcher explains that treatments enable patients to tolerate Large doses From the Unacting Food, which at least helps to lose fear of accidental contact with the allergen. “Soon more treatments will come to various mechanisms,” he concludes.