Medically reviewed by
Kena Shah, DO
Food allergies affect approximately 6 percent of children younger than three years of age and 4 percent of adults in the United States. Those percentages may sound small at first, but according to the American College of Allergy, Asthma and Immunology (ACAAI), more than 50 million people suffer from some type of allergy, and food allergies seem to be developing an increasing prevalence in both the United States and other developed countries.
Food allergies are most common in infants and young children. However, they may occur at any age. An adverse food reaction is a generic term referring to any abnormal reaction after ingestion of food. While adverse food reactions may mirror minor food allergy symptoms, they are not the same. Adverse food reactions may be secondary to a food allergy but more commonly could be related to a food intolerance or sensitivity.
Unfortunately, the prevalence of a food allergy diagnosis also appears to be increasing around the globe. For example, one study found a five-fold increase in peanut allergies in the United Kingdom between 1995 and 2016. We’re seeing indications of similar increases in the United States. Recent events involving childhood and collegiate deaths related to food allergies have reinvigorated a call to improve awareness and understanding.
So let’s tackle the ultimate question: do you have food allergies? If you have had an adverse reaction after ingesting a specific food, the answer could be yes. More likely, however, is the possibility that you have a food intolerance or sensitivity.
This article will dive deeper into food allergies and intolerances to help you determine which is most likely in your situation. It will also help you identify symptoms and diagnosis methods, as well as provide advice on how to safely manage your food allergy.
What Causes Food Allergies?
An allergy refers to an immune system reaction that is unnecessary. These reactions can occur in response to various stimuli, including medications, dust, insect bites and even food proteins that are not actually harmful to a person. The immune reaction, however, can be uncomfortable or even dangerous depending on its severity.
When a food allergy exists, the immune system responds by producing immunoglobulin E (IgE) before the person ever consumes the particular food protein. When consumed, IgE reacts with the specific food protein and leads to food allergy symptoms that can range from irritating to life-threatening
Food Intolerances
Unlike an allergy to a food protein, a food intolerance involves non-immune system functions. For instance, the lack of a specific enzyme responsible for digesting certain foods, such as lactase, can interfere with digestion and cause adverse gastrointestinal (GI) symptoms when the food is consumed. That is an example of a food intolerance. Food intolerances actually comprise the majority of adverse food reactions
Determining if You Have an Allergy or an Intolerance
To determine if you have a food allergy or a food intolerance, you can evaluate the food that’s causing the problem and how you’re reacting to it. In most cases, we also recommend you speak to a qualified allergist who can more definitely diagnose an intolerance or allergy. A professional opinion will help you pinpoint the cause of your reaction and develop an appropriate management plan.
What Are the Most Common Allergies to Food?
Although, any food can cause a food allergy, 90 percent or more of allergic reactions are caused by specific common triggers. In children, cow’s milk, wheat, soybeans, eggs, and peanuts are the most common offenders. While peanuts, tree nuts, and shellfish are the most common foods involved in food allergies in adults.
Although we used to think that childhood food allergy to milk, eggs, and wheat would usually be outgrown by five years of age, new studies suggest that for approximately half of those children won’t see their allergies resolved until the teenage years. Strict avoidance of the food from the diet increases the probability that the food allergy will resolve. Some allergies to food, such as peanuts, tree nuts, and seafood, tend to be life-long and can be quite severe. Additionally, siblings of a child allergic to peanuts have a four-fold increased chance of developing their own peanut allergy.
Additional risks for developing allergies to food occur within the environment. Exposure to microbes and pollution—as seen in urban areas—increases an individual’s risk of developing an allergy.
What Are the Symptoms of a Food Allergy?
Food allergy symptoms are similar to those of other allergies. However, when you eat a food you’re allergic to, you’re exposing your body to a much higher dose of the allergen than if you encountered some pollen on the way home from work. As a result, even eating a small amount of the allergen or simply coming into contact with the product through the skin can trigger the reaction.
Symptoms of food allergy can include:
- Hives
- Swelling of the throat
- Breathing difficulties
- Itchiness of the mouth
- Abdominal pain
- Decreased blood pressure
- Vomiting
- Diarrhea
- Loss of consciousness
- Shock
- Anaphylaxis
When the allergens come into contact with the skin, hives or eczema may form rapidly. Wheezing may occur and if the throat begins to constrict, it can become difficult for severe allergy sufferers to breathe.
Reactions often start immediately on contact with the food in the mouth, or within minutes in the case of severe allergy. If there is a delayed reaction, you’ll typically see symptoms within 30 minutes. It is rare to see symptoms begin two hours or more after ingestion.
The most severe form of an allergic reaction, known as anaphylaxis, is an exacerbated and accelerated multi-system IgE-mediated reaction that can be fatal. The foods responsible for a disproportionate percentage of anaphylactic reactions are peanuts, tree nuts, and seafood. Individuals at increased risk for fatal anaphylaxis include those with underlying asthma, denial or failure to recognize progressing symptoms, delayed treatment with emergency medicine called epinephrine, and a history of prior severe allergic reactions.
More importantly, children and young adults have an especially higher risk of such reactions due to either an inability to obtain the medication fast enough or by not knowing an allergy exists in the first place. Epinephrine must be administered immediately to stop the reaction. Ultimately, asphyxiation or suffocation is the primary cause of mortality when a person enters anaphylaxis. An estimated 500 deaths annually are due to food allergy.
How to Diagnose a Food Allergy
To diagnose your food allergy, you’ll typically follow three general steps, with the help of your allergist.
- Compile a history of your reactions to the specific food in question.
- Evaluate the length of time between ingestion of the food and development of symptoms. (timing of symptoms)
- Determine whether similar symptoms have occurred on other occasions when the food was eaten. (consistency of symptoms with repeated exposure.)
- Undergo one or more food allergy tests.
Since food allergies may include a host of similar foods (those with an allergy to crab may also have an allergy to lobster), any reactions to similar types of food should be included in the history you give your allergist.
When undergoing tests, you’ll go through screening that looks for evidence of food-specific IgE antibodies and proof of reactivity through elimination diets and oral food challenges.
Skin Prick Tests and Blood Allergy Testing
Skin prick tests and blood allergy testing (such as RAST and ImmunoCAP) are performed to document the presence of specific IgE antibodies. These forms of allergy testing, however, can be falsely positive in some cases, so they should be combined with personal observances and, if possible, the oral food challenge.
The Oral Food Challenge
The oral food challenge is considered the gold standard in diagnosing food allergies. The oral food challenge requires that allergy sufferers ingest small amounts of the foods they may be allergic to. Since it involves physically consuming the foods in question, the oral challenge is one of the most accurate diagnostic methods.
It also carries a high risk for those with a likely severe allergy, such as the allergy to peanuts. As a result, this procedure is performed in the medical office setting, where incremental doses of the food are ingested. Staff carefully monitor the person for the development of symptoms, including severe reactions. These are given to patients who meet certain criteria for their food allergies and we want to see if they have moved passed their allergy. We want our patients to succeed so these many details go into the decision to conduct oral food challenges with our patients. Our staff carefully monitors all food challenges to watch for any reactions and can administer treatment or epinephrine to stop the reaction and provide medical assistance. We are having great success with Food Challenges and are happy to report that many patients are passing these weekly.
Changes in Allergies Over Time
Food allergies are not always a lifelong ordeal, they can decrease over time, but you’re also not safe from food allergies just because you didn’t have any as a child. You can develop an allergy or intolerance to different foods over time. In other words, the same allergies present in children may gradually decrease in severity with time and adults may develop an allergy to a food that never caused problems before. Therefore, follow-up skin and blood tests and oral challenges are often performed to determine whether a food allergy exists.
Also, oral immunotherapy, (OIT), is being use more often. While there is no cure for food allergies, OIT is aimed at reducing the risk of severe allergic reactions with accidental exposures. OIT achieves this goal by slowly introducing amounts of the allergen into the patient’s body. Over time, the patient will receive greater doses, which builds up tolerance. Ultimately, this may reduce the severity of allergic reactions. Call us today so we can discuss if OIT is an option to consider.
How to Manage Life with Allergies
Strict avoidance of the implicated food is currently the only proven form of treatment for allergies to food, although treatments such as peanut oral immunotherapy are undergoing evaluation for FDA approval. Two doses of self-injectable epinephrine always need to be available since approximately 25 percent of food-related anaphylactic reactions require a second dose of epinephrine. Antihistamines are used to treat milder reactions and as ancillary treatment with epinephrine. An emergency care plan in writing should be given to schools and caregivers of food-allergic children. A similar plan should also be given to the RA and roommates of college students with allergies to food.
If you suffer from food allergies, we recommend you:
- Avoid the food(s) you’re allergic to.
- Tell friends and family members what you’re allergic to and how severe your reactions usually are.
- Keep at least two doses of self-injectable epinephrine available and ensure friends and family members know where you keep it.
- Inform appropriate school, daycare, or employment personnel about your allergy and how you would like a reaction to be handled.
Educating those around you about your allergies may be just as important as being aware of your condition personally. Your friends, family, and even your coworkers could step in to avert a severe reaction.
Choose an Experienced Caregiver for Allergy Treatment
While there is no cure for food allergies, multiple research studies are ongoing in the quest for a cure. Moreover, research into the causes of such allergies holds additional promise and may be key to preventing them from developing.
Further information about allergies to food is available through the Food Allergy & Anaphylaxis Network at www.foodallergy.org. For assistance in managing your known food allergies or to find out if you have any such allergies, please schedule a consultation with Carolina Asthma and Allergy Center by calling 1-704-372-7900 today or contacting us online. We provide allergy testing, treatment, and personalized care recommendations that can help you manage food and other allergies.