Could It Be a Food Allergy?

Maybe you’ve noticed that your stomach gets cranky after you have a bowl of cereal with milk, or your child gets red itchy skin bumps after certain meals or snacks. You may be wondering whether these are signs of food allergies or if they are caused by something else. Here’s the lowdown on food allergies and what to do if you think you might have one.

What are the symptoms of a food allergy?

Mild food allergy symptoms can include itchiness or tingling in your mouth, vomiting, diarrhea, and skin irritations (hives, eczema, swelling, and itching). More serious allergy symptoms are trouble breathing or wheezing, tightening of the throat, and a drop in blood pressure.

What happens with a food allergy?

A food allergy is when the body’s immune system responds to a particular food like it is a threat, triggering an allergic reaction.  An allergic reaction to food usually takes place within minutes to a few hours after eating the food. An allergic response to food can be mild, moderate, or severe. A severe reaction, also called anaphylaxis, is a life-threatening emergency and requires immediate medical attention.

What foods most commonly trigger allergic reactions?

In adults, the most common foods that cause allergic reactions are fish, shellfish, peanuts, and tree nuts such as walnuts.

For infants and children, the most common foods that cause allergic reactions are eggs, milk, peanuts, tree nuts, soy (primarily in infants), and wheat. Many children outgrow allergies to milk and eggs as they get older, but severe allergies to foods such as peanuts, fish, and shellfish often last into adulthood.

What is the difference between food allergy and food intolerance?

Food intolerance, or food sensitivity, is when the body is not able to digest a particular food or a food irritates the digestive system. Examples of common food intolerances are lactose intolerance, in which milk gives people stomach upset, and intolerance to monosodium glutamate (MSG), which makes some people feel flushed and warm, have a headache, or feel chest discomfort. Food intolerances involve the digestive system, whereas food allergies involve the immune system. Some food intolerance symptoms are similar to food allergy symptoms and can include nausea, gas, cramping, abdominal pain, diarrhea, irritability, nervousness, or headaches. While food intolerance can make you feel ill, it is not a potentially life-threatening reaction like some food allergies.

How is a food allergy diagnosed?

Food allergies are diagnosed by a healthcare provider, most often an allergist, which is a doctor who specializes in allergy and immunology. Allergists have special training in the diagnosis and treatment of allergies, asthma, immune deficiencies, and other immunologic diseases. Your allergist will ask questions about your medical history, do a physical exam, and ask you about the foods you eat. The allergist will want to know about your symptoms: what symptoms you have, how often, how mild or severe they are, and how soon after you eat you have reactions. You might get allergy skin tests to find out which foods if any, trigger allergic symptoms.  

What do I do if I have a food allergy?

If you are diagnosed with a food allergy, you will need to stop eating that food. Your healthcare provider will teach you how to avoid eating foods that can trigger your allergy. Your healthcare provider will also provide instructions on how to treat emergency reactions, such as with antihistamines or an auto-injector device containing epinephrine (e.g., EpiPen®). You may need to wear a medical alert bracelet or necklace indicating that you have a food allergy.

Teach friends, family members, and caregivers how to use epinephrine in an emergency. If you have a reaction, have someone take you to the emergency room even if you are no longer having symptoms and follow up with your allergist afterward.

How can I be sure to avoid foods that cause allergic reactions?

Ask your healthcare provider to give you a list of ingredients or foods to avoid. Read labels carefully on the foods you eat to avoid accidental exposure to food allergens. Always ask about ingredients when eating at restaurants or when you are eating foods prepared by others.

These articles are not a substitute for medical advice, and are not intended to treat or cure any disease.  Advances in medicine may cause this information to become outdated, invalid, or subject to debate. Professional opinions and interpretations of scientific literature may vary.  Consult your healthcare professional before making changes to your diet, exercise or medication regimen.

Sources:

Food Allergy, Medline Plus, National Institutes of Health:  
http://www.nlm.nih.gov/medlineplus/foodallergy.html

Understanding Food Allergy, National Institute of Allergy and Infectious Diseases:
http://www.niaid.nih.gov/topics/foodallergy/understanding/Pages/default.aspx

Food Allergies, American Academy of Family Physicians:
http://familydoctor.org/familydoctor/en/diseases-conditions/food-allergies.printerview.all.html

Food Allergy: Tips to Remember, American Academy of Allergy Asthma and Immunology:
http://www.aaaai.org/conditions-and-treatments/library/at-a-glance/food-allergy.aspx

American Academy of Allergy Asthma and Immunology: http://www.aaaai.org/conditions-and-treatments/conditions-dictionary/food-Intolerance.aspx

Food Allergies, Kids Health from Nemours:
http://kidshealth.org/kid/ill_injure/sick/food_allergies.html

These articles are not a substitute for medical advice, and are not intended to treat or cure any disease. Advances in medicine may cause this information to become outdated, invalid, or subject to debate. Professional opinions and interpretations of scientific literature may vary. Consult your healthcare professional before making changes to your diet, exercise, or medication regime.