Soy allergy is a type of food allergy. This is the hypersensitivity to food substances from soybeans that cause excessive reactions of the immune system that can cause severe physical symptoms for millions of people. The Asthma and American Allergy Foundation estimates that soy is one of the eight most common food allergens for child and adult food allergy patients. Usually treated with exclusion diets and avoid foods that may be contaminated with soy ingredients. The most severe food allergy reaction is called anaphylaxis and is a medical emergency requiring immediate attention and treatment with epinephrine.
Video Soy allergy
Signs and symptoms
Food allergies can have a rapid onset (from seconds to an hour) or slow onset (from hours to days) depending on the mechanism. Symptoms may include: rash, itching, itching, lips, tongue, throat, eyes, skin, or other areas, swelling of the lips, tongue, eyelids, or whole face, difficulty swallowing, runny nose or nasal congestion, hoarseness, wheezing, shortness of breath, diarrhea, abdominal pain, light headache, fainting, nausea and vomiting. Allergy symptoms vary from person to person and can vary from one incident to another. A serious danger of allergies can begin when the respiratory tract or blood circulation is affected. The first may be indicated by wheezing, airways and blocked cyanosis, the last by a weak pulse, pale skin, and fainting. When these symptoms occur an allergic reaction is called anaphylaxis. Anaphylaxis occurs when IgE antibodies are involved, and areas of the body that are not directly in contact with food are affected and show severe symptoms. Untreated, this can proceed to vasodilatation, low blood pressure situations called anaphylactic shock, and death (very rarely).
Non-IgE-mediated reactions are slower, and tend to manifest as gastrointestinal symptoms, without cutaneous or respiratory symptoms. In non-IgE reactions, doctors differentiate between food-induced enterocolitis syndromes (FPIES), food-induced allergy-induced proctocolitis (FPIAP) and protein-induced enteropathy (FPE). Common trigger foods for all are soy baby formula, and also cow's milk formula. FPIAP is considered at the lower end of the lighter spectrum, and is characterized by intermittent bloody stools. FPE is identified by chronic diarrhea that will be lost when the offending food is removed from the baby's diet. FPIES can be severe, characterized by continuous vomiting 1-4 hours after food containing allergens, to the point of lethargy. Aqueous and sometimes bloody diarrhea can develop 5-10 hours after a trigger meal, to the point of dehydration and low blood pressure. Infants who react with soy formula can also react to cow's milk formula. International consensus guidelines have been established for the diagnosis and treatment of FPIES.
Maps Soy allergy
Cause
Soy protein sources
Many fast food restaurants usually use soy protein in hamburger buns (soy flour), hamburger meat (soy protein) and hydrolyzed vegetable protein (HVP) in sauce. On their respective websites, McDonald's and Burger King include soy flour as an ingredient in their hamburger buns. US Nutrition Information Multi-grain bread, donuts, mixed donuts and pancake mixture generally contain soy flour. Almost all bakery products available in the US now contain soy. Soy can now be found in almost all types of food, from meat to ice cream, cheese, to fries. Many foods are contaminated with soybeans because they are cooked in soybean oil. At the Jack in the Box fast food chain for example, all fried ones are cooked in soybean oil. At Baskin Robbins, more than half of the ice cream on offer contains soy. Canned tuna may contain vegetable broth containing soy protein. Some products [for reasons related to national regulations of soy products] do not include soy protein or soy flour on their ingredients label, but they still contain soybeans.
Products containing soy protein include:
- edamame
- miso
- natto
- shoyu sauce
- Me (I'm albumin, I'm fiber, I'm flour, I'm porridge, I'm milk, I'm crazy, I'm sprouts)
- soybeans (curds, granules)
- soy butter
- I am protein (concentrate, isolate)
- I'm milk
- I willow, tamari
- tempe
- textured vegetable protein (TVP)
- hydrolyzed vegetable protein (HVP)
- know
The following food additives may contain soy protein:
- flavorings (including natural and artificial)
- prepares broth, including chicken stock, vegetable stock, and bunillon broth
Cross reactivity with dairy products
Infants - whether still 100% breastfeeding or partly/whole on infant formula - as well as young children - may be susceptible to combined cow's milk and soy protein allergies called "milk soy protein intolerance" (MSPI). The US state government website presents the concept, including recommendations for breastfeeding mothers to stop eating any food containing milk or soy ingredients. Contrary to this recommendation, a published scientific review states that there is insufficient evidence in human literature to conclude that the avoidance of maternal dietary foods during breastfeeding will prevent or treat allergic symptoms in breastfed infants.
A review presents information on soy allergies, milk allergies and cross reactivity between the two. Milk allergy is described as occurring in 2.2% to 2.8% of infants and decreases with age. Soy allergy is described to occur at zero to 0.7% of young children. According to several studies cited in the review, between 10% and 14% of infants and children with confirmed cow milk allergies will also be sensitive to soy and in some cases have clinical reactions after consuming soy-containing foods. This study does not address whether the cause is two separate allergies or cross-reactions due to similarities in protein structure, as occurs in cow's milk and goat's milk. Recommendation is that infants diagnosed with infant formula allergy will switch to an extensive protein hydrolyzate formula rather than a whole soy protein formula.
Dose tolerance
Many people with soy allergies can tolerate small or moderate soy protein quantities: the typical dose required to induce an allergic response is about 100 times higher than other food allergens.
Mechanism
Conditions caused by food allergies are classified into three groups according to the mechanism of allergic response:
- IgE-mediated (classic) Ã, - the most common type, manifests acute changes that occur immediately after eating, and may develop into anaphylaxis
- Non-IgE-mediated - characterized by an immune response that does not involve immunoglobulin E; can occur for hours to days after a meal, complicated diagnosis
- IgE and non-IgE-mediated - hybrid of the above two types
Allergic reactions are the hyperactive responses of the immune system to generally harmless substances, such as proteins in the foods we eat. Why do some proteins trigger an allergic reaction while others are not entirely clear, although some are thought to be caused by resistance to digestion. Because of this, intact or mostly whole proteins reach the small intestine, which has many white blood cells involved in the immune response. Cooking heat structurally destroys protein molecules, potentially making them less allergenic. Allergic responses can be divided into two phases: the acute response that occurs immediately after exposure to the allergen, which may subside or develop into a "final phase reaction," extends the response phenomenon and results in more tissue damage.
In the early stages of an acute allergic reaction, lymphocytes previously sensitive to a particular protein or fraction of the protein react quickly produce a specific type of antibody known as secreted IgE (sIgE), which circulates in the blood and binds to specific IgE receptors on the surface of other immune cell types called mast cells and basophils. Both are involved in an acute inflammatory response. Active mast cells and basophils undergo a process called degranulation, where they release histamine and other inflammatory chemical mediators called (cytokines, interleukins, leukotrienes, and prostaglandins) into surrounding tissues causing some systemic effects, such as vasodilation, mucus secretion, stimulation nerves, and smooth muscle contractions. It causes a runny nose, itching, shortness of breath, and potentially anaphylaxis. Depending on the individual, the allergen, and the mode of delivery, the symptoms may be a system (classical anaphylaxis), or localized to a particular body system; asthma is localized to the respiratory system while eczema is localized to the skin.
After the chemical mediator of the acute response subsides, the late-phase response can often occur due to the migration of other white blood cells such as neutrophils, lymphocytes, eosinophils, and macrophages to the initial reaction site. This is usually seen 2-24 hours after the original reaction. Cytokines from mast cells can also play a role in the persistence of long-term effects. The final phase response seen in asthma is slightly different from other allergic responses, although they are still caused by the release of mediators from eosinophils.
Diagnosis
The diagnosis of soy allergy is based on the history of a person's allergic reaction, skin prick test (SPT), patch test and measurement of serum specific E-serum immunoglobulin E protein (IgE or sIgE). Negative IgE tests do not rule out non-IgE-mediated allergies, also described as cell mediated allergens. SPT and SIgE have sensitivity of 55% and 83%, respectively 68% and 38%. These numbers mean that one test may miss diagnosing the soy allergies present, and that both can also be positive for other food allergens. Confirmation is a double-blind, placebo-controlled food challenge, conducted by an allergy specialist.
Treatment
Treatment for ingestion of unintentional soy products by an allergic individual varies depending on the person's sensitivity. Antihistamines such as diphenhydramine (Benadryl) may be prescribed. Sometimes prednisone will be prescribed to prevent the possibility of slow phase I type hypersensitivity reactions. Severe allergic reactions (anaphalaxis) may require treatment with epinephrine pens, that is, injection devices designed for use by non-health care professionals when emergency care is justified. The second dose is required in 16-35% of the episodes.
Society and culture
Whether food allergy prevalence is increasing or not, awareness of food allergies is really increasing, with an impact on the quality of life for children, their parents and their immediate caregivers. In the United States, the Food Labeling and Consumer Protection Act of 2004 caused people to be reminded of allergy problems every time they handled food packages, and restaurants added alerts to the menu. Soy is one of eight foods with mandatory labeling required. The Culinary Institute of America, the main school for chef training, has an allergen-free cooking course and a separate teaching kitchen. The school system has a protocol about what foods can be brought to school. Despite all these precautions, people with serious allergies are aware that unintentional exposure can easily occur in other people's homes, in schools or in restaurants. Fear of food has a significant impact on quality of life. Finally, for children with allergies, their quality of life is also influenced by the actions of their peers. There is an increase in the occurrence of bullying, which can include threats or deliberate actions touched with foods they need to avoid, as well as having contaminated allergen-free foods.
Genetically engineered food
There are concerns that genetically modified foods, also described as foods derived from genetically modified organisms (GMOs), can be responsible for allergic reactions, and that widespread acceptance of transgenic foods may be responsible for what is real or perceived increase in percentage of people people with allergies. One concern is that genetic engineering can make food allergies more allergic, meaning that smaller portions will be enough to trigger a reaction. Of foods currently used widely by GMOs, only soybeans are identified as common allergens. However, for soy proteins that are known to trigger allergic reactions, there is more variation from strain to strain than between them and transgenic varieties. The same review quoted a US National Academy of Sciences report concluding, "The committee found no association between GE food consumption and increased prevalence of food allergies."
A second concern is that genes transferred from species to other species can cause allergens in foods that are not considered allergenic. Research on efforts to improve the quality of soy protein by adding genes from Brazil nuts is terminated when human volunteers are known to have tree nut allergies reacting to modified soybeans. Currently, before new GMO foods receive government approval, certain criteria must be met. These include: Are donor species known to cause allergies? Is the amino acid sequence of the transferred protein resembling a known sequence of allergen proteins? Will the transferred proteins be in the plant part to be eaten (as opposed to roots, stems or leaves that are not consumed)? Is the transferred protein resistant to digestion - a trait possessed by many allergenic proteins? Finally, there are requirements in some countries and recommendations elsewhere that all foods containing GMO ingredients are labeled in such a way, and that there is a post-launch monitoring system for reporting adverse effects (many in some countries for reporting drug and food supplements). According to a 2015 report from the Food Safety Center, 64 countries require the labeling of GMO products on the market.
See also
- Allergies (have diagrams that show the involvement of different types of white blood cells)
- Food allergies (have an itchy image, skin prick test and patch test)
- List of allergens (food and not food)
References
External links
- Soy allergy information page. Asthma and Allergy of the American Foundation
- Soy Allergy on Food Allergy Initiatives
Source of the article : Wikipedia
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