Food allergies are common and appear to be on the rise. It is important that a distinction between food allergies and intolerances be made.
Allergy vs. Intolerance
Food allergies by definition are reactions that occur due to an inappropriate or “overreaction” of the immune system to a protein component of a specific food. While any food can cause an allergic reaction, the majority of problems are from a select group of allergens. Common food triggers can vary based on age with cow’s milk, wheat, egg, and soy being seen in infants and younger children and peanut, tree nut, fish, and shellfish being more common in older children and adults. Signs and symptoms of food allergy reactions include one or more of the following:
- A rash or red, itchy skin
- Stuffy or itchy nose, sneezing, or itchy and teary eyes
- Vomiting, stomach cramps, or diarrhea
- Angioedema or swelling
- Hoarseness, throat tightness, or a lump in the throat
- Wheezing, chest tightness or trouble breathing
Severe reactions, called anaphylaxis, involve multiple body systems. Anaphylaxis is a medical emergency and can be fatal.
A food allergy diagnosis is primarily based on a detailed history with selective skin and/or blood testing used as a complement to confirm a suspected diagnosis gleaned from the patient’s story. Food allergy testing should never be done “just to be sure I don’t have any allergies” as this puts you at high risk for incorrect test results, misdiagnosis, and unnecessarily limiting what foods you eat. Once a food allergy is diagnosed by a board-certified allergist, it is crucial that proper education takes place and evidence-based recommendations are followed.
Food intolerances result in non-life threatening, although often times distressing symptoms. In many cases, the exact immunologic process taking place in the body is not known. A common food intolerance is lactose intolerance. Individuals with lactose intolerance will have issues digesting cow’s milk and other dairy products. Symptoms are essentially limited to the gastrointestinal tract and may include nausea, abdominal pain/bloating, gassiness, and loose stools. Symptoms generally do not affect the skin or breathing, however, some individuals note increased mucus production with dairy exposure. Any food can potentially result in symptoms of intolerance. There is currently no reliable test for food intolerances and the best step is to keep a detailed food diary to determine a possible cause. If a problematic food is suspected, an elimination of that food of concern is recommended along with monitoring of symptoms. If symptoms improve or resolve, there is a good chance that the specific food is contributing to symptoms and should continue to be avoided.
Fact vs. Fiction
Now that you know some differences between food allergies and food intolerances, let’s dispel some common myths about food allergies.
Myth #1: I have a peanut allergy and will have issues with casual contact or inhalation of peanut dust/vapors.
Fact: Evidence demonstrates that inhalational exposures to peanut products in public places like schools, sporting events, and airlines are highly unlikely to trigger allergic reactions. Studies also show that while patients may experience local irritation at sites of allergen contact, this exposure is unlikely to trigger a major reaction.
Myth #2: I can no longer eat at a restaurant that cooks with an oil-related to my food allergy or consume foods containing that oil.
Fact: Evidence indicates that those with a peanut allergy can safely tolerate highly refined oils but not cold-pressed or expeller-pressed oils, so verifying those details is critical. Sesame oil is often unrefined and may contain allergic protein, so avoidance for sesame allergic individuals is typically recommended. Soy oil and soy lecithin, a fatty substance with little allergic potential often used as a food additive, are well tolerated among those with a soybean allergy.
Myth #3: A food allergy ban is needed to protect my child at daycare or school.
Fact: The idea of reducing exposure to an allergen in a school or daycare setting may seem logical, but specific studies have shown no difference in the use of epinephrine auto-injectors between schools allowing peanut and those not allowing peanut. Even if a school chooses to ban specific foods, there is no guarantee that restrictions can be enforced or fully implemented to ensure allergens will not enter the building. Instead, preferred measures should be in place such as having an anaphylaxis management plan with epinephrine treatment available if needed. Implementing evidence-based strategies, such as hand-washing and surface cleaning after food contact, are more likely to be beneficial.