Food allergies are immune system reactions to food proteins that the body identifies as foreign. Symptoms can vary widely, and it is important to distinguish between food allergy and toxic reaction and the duration of symptoms.
Food Allergies: what they are and why they occur
Food allergy is an abnormal reaction, non - toxic and immunological mechanisms mediated response to food proteins (or any exogenous antigen) ingested, inhaled or contact, and causes different symptoms. This occurs because the body identifies such a food as foreign proteins, and reacts with the production of immunoglobulins (Ig). It is usually caused by proteins and glycoproteins with MW of 5-100 kDa and are usually resistant to acid pH, digestive enzymes and cooking.
Prevalence of food allergies
In atopic individuals the incidence may be about 10%. However, the perception of food allergy is much higher than the actual allergy, showing only 30% of patients with suspected. Adult allergy can come from childhood or appear de novo. Also, there may be a genetic predisposition to food allergies, and other allergies that may present a patient.
Causes of food allergies
Regarding the causes that can provide a food allergy we may find disorders of the intestinal mucosa barrier. This can be common in young children who, for one immaturity of this barrier, penetrate some food antigens, facilitating the emergence of some allergies, especially milk and egg disappear with age.
Also important is genetic predisposition, the formation of IgE antibodies against food proteins. On the other hand, the eating habits of each patient can also provide some food allergies.
Food allergies causing foods
Any food can cause food allergy, although children under 2 years of age, the most common allergies are cow 's milk and egg. Also, while any food can cause allergies in adults, the most frequently involved are the nuts and Rosaceae fruits, including peach is. They may also be important vegetables, legumes, fish and seafood.
Difference between food allergies and toxic reactions
The actual allergic reactions should be differentiated from toxic reactions. In these cases the reaction will affect most individuals who ingest food that. On food intolerance is a food type of adverse reaction by a nonallergic mechanism. Intolerances within we can find patients who, for example, have enzyme deficiencies such as, for example, lactose intolerance or fructose.
Symptoms of food allergies, factors that can strengthen it and diagnosis
Symptoms that can appear in a food allergy are varied. One of the most frequent and milder time is called oral syndrome, in which the food to which it is allergic may cause itchy mouth. more severe reactions, as can be urticaria may occur with skin involvement. It also may involve gastrointestinal involvement, abdominal pain, vomiting and diarrhea. In some patients allergic respiratory symptoms may also occur with inhalation of vapors from cooking some foods. The most severe reaction is anaphylaxis, which is a generalized allergic reaction that can compromise the patient's life.
In some circumstances the only food sensitization no symptoms if no what is called cofactor. These are some factors which are exercise and anti-inflammatory medications such as aspirin or alcohol, which can enhance the allergic response.
In food allergy symptoms appear quickly, in less than 1 hour, except if a cofactor that can delay 2-3 hours. There will be no suspected food allergy if they have spent many hours from the ingestion of food.
Avoiding food allergies
Once the patient has been diagnosed with allergic must avoid eating such food. However, sometimes it can be difficult in so-called hidden food. These can be:
- Foods in which the patient is not aware of being by ingesting, such as sauces, of which one can not know the composition (for example, nuts)
- foods that are contaminated by other or containing small amounts
- foods that have been in contact with others (like a fruit that has touched other)
- instruments not properly washed in the kitchen has been previously cooked some food to which the patient is allergic
- Anisakis simplex, a parasite that can have sometimes fish.
Sometimes a patient appears to be allergic to many foods and this may be because it has some protein in common to which the patient is allergic.
It is important that all patients with suspected food allergy is visited by a specialist in Allergology , to confirm or rule out allergy and receive the best treatment in each case.
Edited by Noelia García Pino