Whether you’re grocery shopping or reading from a menu, allergen information is becoming more common information provided to consumers.  This is great if you have a sensitivity or allergy to foods, so you don’t have to guess whether you can safely eat something or not. It can also, in some cases, provide more safe choices for you since sometimes you may avoid foods that you suspect contain allergens, but really do not. However, when someone asks you whether you have a food allergy or intolerance, the lines can become blurred and the terms sometimes are used interchangeably. However, there are very distinct differences between food allergies and intolerances that can impact treatment of such conditions.

Food Allergies vs. Intolerances

A food allergy is an immune response to a trigger food. This immune response usually results in symptoms such as:  

• Hives
• Shortness of breath
• Wheezing
• Tightened throat
• Repetitive cough
• Swelling of the tongue
• Vomiting or stomach cramps

Other more severe symptoms of food allergies can include dizziness, fainting, pale or blue coloring of the skin, and/or anaphylaxis that can lead to shock and impaired breathing. Symptoms usually start within minutes up to two hours after ingestion of the trigger food. Common food allergies include wheat, cow’s milk, peanuts, tree nuts, soy, eggs, shellfish, or finned fish.

On the other hand, a food intolerance usually involves symptoms that are more non-specific.  Food intolerances may also be referred to as hypersensitivities. No matter what you call it, typical symptoms of a food intolerance usually involve the digestive system, like those associated with irritable bowel syndrome.  Such symptoms include gas, bloating, abdominal cramps, diarrhea and/or constipation. Food intolerances are usually caused by one or more of the following:

• Lack of enzymes to break down certain foods (e.g. those with lactose intolerance lack the enzyme lactase that helps to break down the milk sugar lactose).
• Sensitivities to food additives
• Reactions to naturally occurring food compounds

Celiac disease is one case where it may be difficult to distinguish whether it is a food allergy or intolerance. The condition involves intestinal damage and painful digestive symptoms when a person ingests the protein gluten that is found in wheat, barley, and rye.  Because of these primarily digestive symptoms, it is considered more of a food intolerance. Although those with celiac can experience some of food allergy symptoms. However, one thing that makes celiac disease a food intolerance more than an allergy is that those with the condition are not at risk for anaphylaxis.

Do you have a food allergy or intolerance?

By keeping a symptom diary alongside your food diary, you may be able to look at the symptoms above and determine whether you have a food allergy or food intolerance. However, it can also be helpful to visit a dietitian or other qualified healthcare provider to test you for food allergies.  Examples of testing for allergies and intolerances include:

• Elimination diet: This involves eliminating the common food allergens for a period of time, usually at least two weeks up to a few months. Under the supervision of a dietitian or other qualified healthcare provider, you would add in certain foods slowly to try and figure out which are causing your symptoms.
• Skin prick tests: This quick test involves exposing the skin to a liquid form of certain food allergens and watching for immune systems such as inflammation and swelling to develop. This reaction will be compared to a control skin prick which will not be exposed to any allergens.
• Blood tests: Blood tests for allergens or intolerances involve taking a blood sample and testing it for antibodies to certain foods and food compounds. This type of testing is not considered as exact as skin prick tests.

How to treat food allergies vs. intolerances

Food intolerances and allergies can usually be treated by making changes in the diet.  Once trigger foods are determined through testing, these foods can be eliminated from the diet to control symptoms. Those with a food allergy or intolerance will have to be extra careful to read nutrition labels and allergen statements for restaurants they may visit or food products they may buy.

Those with food allergies may also have to carry around medicines such as antihistamines and/or epinephrine in case of exposure to a food allergen.  Also, those with a food allergy or a food intolerance may find it helpful to carry around a card with them explaining their condition. This can make it easy for chefs or other food service staff to make sure their food is prepared safely for them. An example of this is the low FODMAP travel card on the Casa de Sante website.

Take home message

Food allergies and intolerances are two different conditions that should not be confused. Either condition though can be diagnosed with blood, skin, and/or diet-related testing. Once trigger foods are determined, adherence to a diet regimen that avoids trigger foods can help control symptoms. So, get tested, read labels, and stay on track away from trigger foods so you can live your best life with your food allergy or intolerance.