Although one of each three people thinks that she is allergic to some food, according to Guía of European Food Information Council (EUFIC), the reality is that the nourishing allergy affects to only a 2 percent in the adult population. Sometimes the allergy with reactions is confused that can be due to a poisoning or a psychological aversion to a food and, even, to the intolerance to some ingredient. For that reason, it is important to know how to differentiate between an allergy and a intolerance to act suitably in each case.

The dietary intolerance affects the metabolism, but not to the immunological system of the body. That is to say, when the organism cannot digest a food correctly or one of its components. The intolerance can be due to a defect of some enzyme that is in charge to metabolizar that food, to a pharmacological alteration or by unknown cause. The symptoms usually are abdominal pain, nauseas, vomits and diarrhea. Most common they are the intolerance to the lactose and the gluten.

Generally, the people who undergo a intolerance can consume small amounts of the food or the nutritional component cause of the reaction, without symptoms take place, except in the case of sensible people to the gluten.

The allergy is a half-full reaction by an immunological mechanism. A allergen (protein of the food cause, that in the majority of people does not produce adverse reactions) brings about a series of chain reactions in the immunological system, among them, the production of antibodies. These generate the segregation of chemical substances, like the histamina, that produces symptoms cutaneous (inflammation of lips, mouth, language, face and/or throat, urticaria, eruptions or reddening, picazón, eccema), respiratory (moqueo, estornudos, difficulty to breathe, respiratory cough, lagrimeo, sibilancia, upheavals), gastrointestinal (abdominal pain, diarrhea, nauseas, vomits, cólicos, swelling) or systemic (anaphylactic shock). The more common nutritional allergens are the milk of cow, eggs, soybean, wheat, seafood, fruit and fruits droughts.

The majority of the allergic reactions to foods is relatively slight, except in the case of a reduced number of people who undergo a serious reaction with death danger, that anafilaxis or anaphylactic shock is known like. It is possible to be produced to the few minutes of the ingestion and consists of a sudden fall of the sanguineous pressure, that can give rise to a cardiac shutdown. The peanuts are one of the foods that can cause it.

The genetic predisposition is the most important factor of the allergy that, normally, is identified in the first years of life. The best form to predict it is to know the antecedents familiar. The children with a mother or an allergic father have the double of possibilities of developing an nourishing allergy that the children whose parents do not suffer allergies. If both ancestors are allergic, the risk is of to six four times greater.

Generally, the allergic people must stop consuming the food that causes the reaction, since the consequences can be very serious.

Main allergies

The allergy to the protein of the cow milk is more common in babies and children, especially when there are familiar antecedents. One occurs in a 0,5-4 percent of the babies and its prevalence falls with the age. The most common symptoms are the vomits and the diarrhea, although they can vary from a person to another one. The adverse reactions, generally, send soon and the incidence in children of more age and adults is much smaller. When a diagnosis of allergy to the protein of milk is confirmed, it is important to maintain a diet balanced and healthful. For it, he is essential to count on the advising of a specialist to guarantee an optimal ingestion of nutrients like calcium, magnesium and vitamins To, D, B2 and B12. The consumption of sardines and salmon with thorns (in tin) and of cooked green vegetables, like brócoli, aid also to maintain the calcium ingestions recommended.

The allergy to the fruits droughts considers an important affection, since it begins to an early age, lasts all the life and can have fatal consequences. The peanuts, almonds, chestnuts, hazelnuts and nuts can even bring about symptoms when making contact with enemy with the skin or by inhalation. The treatment consists of a free diet of fruits droughts, so the allergic one must read the labels of foods in case they took to plans of fruits droughts. The slight allergy can be limited an eruption, nauseas, headache and inflammation of the language and the lips, whereas the serious one can bring about an anaphylactic shock. For this reason, those people who undergo these reactions will have to avoid any contact with this food and to take adrenalin at any moment to resist a possible serious reaction.

The allergy to the egg appears when the organism produces an antibody, the IgE (immunoglobuline E), directed against a substance that acts like allergen, in this case the egg. As much the proteins of the clear one as of the yolk can act like aeroalérgenos and cause asthma. In some patients, the contact with the egg can cause urticaria, in spite of tolerating its ingestion. Also, there are people who tolerate the cooked yolk and, nevertheless, react before the ingestion of the clear one. The egg is the most frequent cause of nourishing allergy in children. Before both years of life and usually disappears in the first six. Most probable it is than with the course of the time the person is tolerating the food until doing it definitively, although in very particular cases there are some that are sensitized for all the life.

In the case of the seafood, the allergy is more frequent in the adult. Among them, the crustaceans (prawn, prawn, shrimps, crab and lobster) are those that have more probabilities of causing it. Molluscs (clams, oysters, ears of sea, etc.) can be alergénicos, but the reactions are less common. Some people are it to both types of seafood.

The reactions to the fruit can be presented/displayed of two forms. Like an oral allergy, that produces picor in the mouth and throat when eating peach, apple, melon or kiwi, because of a sensitization to a bread-allergen that, in addition, usually one occurs in allergic to pollen. Or like an allergy to proteins of the fruit, generally LTP (transporting lipid proteins), whose symptoms are more serious and can give rise to anaphylaxis. In order to avoid it, it must realize a diet with absolute exclusion of the pomáceas fruits (peach, apricot and derivatives, apple, pear), as well as of plums, figs, cherries, strawberries, melon, kiwi, papaya, avocado, you dwell, etc. will only tolerate citruses (orange, mandarin, grapefruit). Sometimes, an allergy crossed by the presence of bread-allergens in other vegetables can be given and usually it considers the exclusion of crude vegetables, peas, lettuce, endive, lombarda, onion, garlic, etc.

On the intolerances to the lactose and the gluten

The lactose is the sugar that is of natural form in milk. In order to digest it, the precise human organism of the enzyme lactasa, that takes place normally in the intestinal mucosa and that transforms the lactose into smaller units (glucose and galactosa) so that they can be absorbed by the blood. The intolerance to the lactose must to the diminution or absence of lactasa in the digestive conduit. When the activity of the enzyme is too low, the lactose cannot be digested and happens to the heavy intestine, where it is fermented by the bacteria of the intestinal flora, causing flatulence, pain and diarrhea.

The amount of lactasa in the intestinal mucosa is falling with the age. Therefore, he is relatively frequent that appears typical group of symptoms in ages outposts until in a 15 or 20 percent of the population. For this reason, many people majors leave the milk consumption, which is extremely problematic since they lose an essential calcium source. In order to avoid it, it is precise to include alternative foods like yogurts or cheeses, that cover the daily needs with this mineral, essential for the maintenance of the bony structure.

The capacity to tolerate the lactose varies much from people to others. There are some who they must completely eliminate the milk of his diet and others can take small amounts without upheavals take place. He is advisable also to study from what amount of milk the symptoms take place. Even an amount of milk tolerated, nondistributed in two or more takings to the day, can - in many cases of not causing intolerance. Other people can take ice creams and some types from yogurts or cheeses, but not another class of milky derivatives. The adults can tolerate of about 100 to 200 milliliters of milk in a single taking, which supposes between 5 and 10 grams of lactose.

The main dietetic recommendations are:

• To assure the daily ingestion two rations of rich calcium foods: milk without lactose, milk of soybean, yogurt or cheese (according to tolerance).

• The cheese of La Mancha cured and roquefort have a minimum contained in lactose.

• Other rich calcium foods: fish that can be eaten with thorn (tin sardines, anchovies…), vegetables, fruits droughts, soybean and derivatives.

• The calcium is used and only is absorbed when sufficient amount of vitamin D in the organism exists. This one is in eggs and fish.

• The exhibition controlled to rays of the sun also contributes to the vitamin synthesis D. The best form to obtain it is to take a walk in days of sun.

• The lactose is used as it bases of more of the 20 percent of medecines with prescription and the 6 percent of medecines without prescription. Nevertheless, these products only affect to people with severe intolerance.

On the other hand, the intolerance to the gluten is an intestinal upheaval that occurs when the body cannot tolerate the gluten, a protein that is in the wheat, the rye and the barley. Still it is a pathology unknown for many people. The Federation of Celiac Associations of of Spain (PHASE) esteem that, at the moment, 1 of each 100 Spanish citizens is celiac, of which only the 10 percent is diagnosed.

The celíaca disease is a permanent intolerance that can be diagnosed to any age. If the patient consumes foods that contain gluten, the mucosa of the thin intestine is damaged and has less capacity to absorb essential nutrients like fats, proteins, carbohydrates, minerals and vitamins. The most frequent symptoms are: loss of weight and appetite, fatigue, nauseas, vomits, diarrhea, abdominal distension, loss of muscular mass, delay of the growth, abdominal alterations of the character (irritability, apathy, introversión, sadness), pains, meteorismo and anemia by iron deficit. Nevertheless, as much in the boy as in the adult, the symptoms can be atypical or to be absent, making difficult the diagnosis.

When the symptoms are clear, it is easy to establish the diagnosis by means of a careful clinical examination and an analytical one of blood, that includes the serologic markers of the celíaca disease. Next, it would be come to the confirmation by means of an intestinal biopsy.

The unique treatment is a diet without gluten. Normally, food lists can be obtained without gluten in dietetic centers and the associations of support related to the celíaca disease. When the gluten of the diet is eliminated, the intestine regenerates gradually and disappear the symptoms. At present, investigations are being realized to identify the nature and the exact sequence of the amino acids of the gluten that produce the celíaca disease and is possible that, in the future, this information has important applications in the biotechnology and the development of cereal cultures that do not cause intolerance.

Generally, the celiac one bases its feeding on foods like vegetables, meats, fish, eggs, fruits, vegetables, vegetables and cereals without gluten (rice and maize). One is due to have well-taken care of with packaged foods, unless in the label of the packaged food it appears the symbol “without gluten�.

MORE INFORMATION: 

• Foundation of the Spanish Society of Allergology and Clinical Immunology: www.seaic.es  
• Spanish association of Allergic to Foods and Latex: www.aepnaa.org
• Institute You take Paschal Sanz for the Nutrition and the Health: www.institutotomaspascual.es
• Federation of Associations of Celiac of Spain (PHASE): www.celiacos.org