Food allergy is an abnormal response of the immune system to a protein in the food it mistakenly perceives as a threat to the body. When the immune system attacks the protein, it causes mild to moderate symptoms, such as wheezing, skin rash, and abdominal cramps. In some cases, these symptoms can progress to a more severe and life-threatening condition called anaphylaxis.
According to the American College of Allergy, Asthma & Immunology (ACAAI), food allergies affect four to six percent of children (1), suggesting that food allergy in children isn’t uncommon. Also, most food allergies appear in early childhood, so parents should stay informed about food allergies in children.
In this post, we discuss the causes, symptoms, timely diagnosis, and treatment options for allergy in children. We also give you a few valuable tips to prevent allergies in children to ensure your child is safe at home and school.
Are Food Allergy And Food Intolerance The Same?
Although food allergy and food intolerance manifest similar symptoms, they are different conditions. Food allergy is an immune system-related condition characterized by an allergic reaction to a food. On the other hand, food intolerance is a digestive disorder characterized by the inability to digest certain foods (2).
Food allergy affects numerous organs in the body and causes mild or moderate to severe symptoms, such as anaphylaxis. In contrast, food intolerance primarily causes gastrointestinal symptoms, and the symptoms are seldom severe (3).
Causes Of Food Allergy
The exact cause of food allergy is not known. However, experts believe that a food allergy develops due to a combination of genetic and environmental factors.
In an episode of food allergy, the body perceives a food protein as an antigen, a potential danger. The body produces specialized proteins called immunoglobulin (IgE) antibodies to fight off the threat. Upon release, these antibodies signal the body to release histamine and other chemicals.
When a child gets a food allergy, they must have been exposed to the food at least once, or they could have been sensitized through breast milk before developing an actual allergic reaction. It means that when a child gets an allergic reaction, it is the second time that the child has contacted the allergen (4).
Foods That Might Trigger Allergy In Children
Although almost any food can trigger an allergic reaction, the following eight foods account for approximately 90% of food allergies (6).
- Fish, such as salmon, cod, and tuna
- Shellfish, such as lobster and shrimp
- Tree nuts, such as almonds, walnuts, pecans, and cashews
Besides these, sesame and mustard seeds are also considered major food allergens in some countries.
Symptoms Of Food Allergy
Allergic reactions to food can cause a range of symptoms, and the severity of these symptoms may vary from one child to another.
The following are the common mild to moderate symptoms of a food allergy in children (1) (4) (5) (6).
- Red spots on the skin (hives)
- Itchy skin rashes (eczema or atopic dermatitis)
- Runny or stuffy nose
- Swelling of the mouth, tongue, or throat
- Sneezing or wheezing
- Abdominal cramps or stomach pain
- Nausea or vomiting
In some cases, anaphylaxis may also occur. Anaphylaxis is a severe and life-threatening reaction that requires immediate medical intervention. The symptoms of a severe allergic reaction include
- Pale or blue-colored skin.
- Swollen neck and itchiness and tightness of the throat.
- Shortness of breath and difficulty breathing.
- Dizziness, with low blood pressure.
- Partial or complete loss of consciousness.
Most food allergy reactions occur within minutes to an hour or two after ingesting a food. In some rare cases, this can occur after four to six hours or even longer.
Note: A reaction after ingesting food isn’t always a food allergy. In some cases, a child may experience an allergic reaction after eating raw or undercooked fruit or vegetables. This condition is called oral allergy syndrome, wherein the body reacts to pollen in the food and not the food itself (1).
Diagnosis Of Food Allergy
1. Physical examination: The doctor will examine the child’s skin and look for signs of rashes. They will also evaluate the child’s vital parameters, such as heart rate and blood pressure. Additionally, the doctor may ask specific questions to the child or their parents, such as
- “What did the child eat, and how much?”
- “How long did it take for the symptoms to develop?”
- “What specific symptoms they had and how long did they last?”
2. Elimination test: This simple test involves eliminating the specific food from the diet and then reintroducing it to check if the reintroduction triggers a reaction. If the pediatrician suspects a food allergy, they will refer you to an allergist for further investigation.
3. Blood test: A blood test helps determine whether the child has food-specific IgE antibodies in the body. If the antibodies are present, the test measures the amount of antibodies present in the blood. The doctor correlated the test results with the information collected during the physical examination.
4. Skin-prick test: This test is the most accurate way to ascertain the cause of food allergies. The test involves placing a small, diluted quantity of suspected allergen on the back of the child’s hand or forearm. The doctor then pricks the skin using a small, sterile probe, which allows the diluted allergen to enter the skin. In a positive test, the child develops a raised, reddish bump on the pricking site within 15 to 20 minutes. This doctor will not perform this test if the child recently had a severe reaction or has chronic eczema or hives.
If the skin or blood tests are inconclusive, the allergist may recommend an oral food challenge test. This test helps determine if the child has outgrown a food allergy.
5. Oral food challenge test: In the test, the child is made to eat a tiny amount of the suspected food under supervision. If there’s no reaction, the amount of food is increased until the child eats a serving of the food. If the child develops a reaction, it indicates a positive case of allergy for the suspected food. This test is done in an allergist’s office with emergency medical arrangements due to its potential of triggering severe allergic reactions.
Treatment For Food Allergy
1. Remove the allergenic food from the diet
Remove the allergenic food and other foods that contain the allergen from the child’s diet. For instance, if your child has a milk allergy, they should avoid milk and milk products. Consult a pediatric nutritionist to devise a well-balanced diet plan and replace the allergenic food with its healthy alternatives.
2. Use oral supplements whenever necessary
Your doctor and pediatric nutritionist can help you determine whether your child needs a supplement. In some cases, where the child has an allergy to multiple foods, such as milk and soy, they may require nutritional supplements to support their dietary requirements.
3. Use oral antihistamines
This can help relieve allergy symptoms, such as swelling, runny nose, or abdominal pain. Consult the pediatrician for the correct dosage. The doctor may also prescribe an epinephrine auto-injector to tackle a severe allergic reaction. Parents should train their child to use the auto-injector and inform the concerned authorities, such as school teachers, about its use for the child.
Several allergies may last for a short time, and some may resolve when the child is three or four years old. Follow-up testing and periodic evaluation of the child’s condition will help determine if the child is still allergic to a particular food.
Prevention Of Food Allergy In Children
1. Avoid feeding allergenic food to your child if they develop an allergy. It involves its derivatives and other foods that could contain the allergen or its derivatives. For instance, if your child has a peanut allergy, they must avoid peanuts and any food that is made from peanuts or contains peanuts. Certain energy bars, cakes, and muffins generally contain peanuts.
2. Read the ingredient list carefully while buying a packaged food. It will help you know if the food contains a potential allergen. Children with food allergies should also learn to read the food label and ingredient list. It will help them stay cautious and responsible in food selection when you aren’t around.
3. Check the restaurant menu carefully and ask the concerned person about a dish and its ingredients while eating out with your child. It will help minimize the chances of an accidental allergic reaction. Alternatively, try to carry homemade food for the child whenever eating out. This way, you can ensure the child is eating safe food. Also, it saves you from the hassle of finding appropriate food for your child, which isn’t always easily available.
4. Encourage your child to always carry an epinephrine auto-injector with them. Train them to use the injector themselves. If your child goes to daycare, playschool, or school, inform the teachers about the child’s condition. Tell them about the food/foods they can’t eat and foods they can eat. Also, guide them on how to use an auto-injector in case of an emergency.
5. Reintroduce a food after consulting your child’s healthcare provider. It applies to cases where you suspect that the child has outgrown the allergy. The doctor will perform specific tests to confirm your suspicions and guide you on how much quantity and how you can begin reintroducing the food to your child.
6. Get social and mental health support for your child and the family. Bringing up a child with food allergies can get overwhelming at times. In such times, talking to parents who have children with allergies can help resolve some anxieties. Also, you and your child can speak to a mental health professional who could educate you on ways to manage allergies and live a happy and productive life.
As your child grows and understands their condition better, they will manage it themselves with minimum support from you or people around them.
Food allergy in children can be bothersome for parents and children. However, one can manage the condition by following the appropriate treatment options and preventive measures. Educate your child about their condition and encourage them to be responsible from a young age. Also, train them to enquire about the ingredients in food and read food labels to avoid accidental allergen intake.
2. Food allergy, intolerance, or sensitivity: What’s the difference, and why does it matter?;Harvard Health Publishing
3. Food Allergy vs. Intolerance: Knowing the Difference;Nationwide Children’s
4. Food Allergies in Children;Johns Hopkins Medicine
5. Food Allergies in Children;University of Rochester Medical Center
6. Food Allergies in Children;AAP
7. Reducing the Risk of Food Allergies;Academy of Nutrition And Dietetics