Food Allergies vs. Food Sensitivities vs. Food Intolerances. Do You Know the Difference?
Too often I see these terms tossed around and used interchangeably in popular media leading to unnecessary confusion and skepticism.
Food allergies, food sensitivities and food intolerances are three very distinct potential adverse food reactions that are all treated very differently – thus they are important to distinguish.
1.) Food Allergies
These are severe, systemic, and immediate immune reactions to foods such as peanuts or shellfish. Food allergies cause the release of food-allergen specific IgE molecules, contributing to histamine and other inflammatory mediators causing body-wide inflammation. Hives, itchy skin, difficulty breathing, vomiting, and anaphylaxis (severe life-threatening allergic reaction), are all symptoms of food allergies. The most common food allergies are to food such as peanuts, shellfish, wheat, eggs, dairy, and soy. There are, however, many other foods that may cause food allergies but are generally much less common. Food allergies generally develop in young children on exposure to different foods. Additionally, children with food allergies tend to also experience asthma, eczema (atopic dermatitis), and hay fever (or allergic rhinitis). This is considered the "atopic triad" or "march", which may suggest an underlying genetic component and altered immune system balance.
2.) Food Sensitivities
Food sensitivities are milder, delayed immune responses to foods. Some foods have the potential to increase systemic inflammation contributing to migraines, joint pain, fatigue and so on. These reactions are harder to identify because they can occur up to 72 hours after consumption and are much more insidious. Unlike food allergies, these are NOT IgE mediated, but rather have been postulated as IgG (or IgG4) and C3d mediated. These are also potentially inflammatory producing molecules created by the immune system, however, are less abrupt and severe in their effects in the body. Additionally, IgG-mediated reactions tend to not have any genetic pattern.
3.) Food Intolerances
Food intolerences are a whole other ballgame. These are NON-immune responses to foods. They are usually confined to the gut causing gas, bloating, diarrhea, pain, and constipation. The most common food intolerance is lactose intolerance (dairy products). There are many more possibilities, however, such as carbohydrate intolerances, biogenic amine intolerance, sulfite sensitivity, and many more. Food intolerances are generally either reactions that occur due to insufficient, or lack of, proper enzyme secretion from our digestive system leading to malabsorption of certain molecules (such as lactose or other carbohydrates), or a result of adverse reactions to certain naturally-containing chemicals or molecules found in foods (such as sulfites in lemon or grape juice).
As you can see, the world of adverse food reactions can be very complex. By using self-assessments and guessing alone to utilize long-term elimination diets can lead to nutrient deficiencies, food-fear, fatigue, low mood, and more. This is why I advocate for reliable, standardized testing and evidence-based treatment.
My main goal is for all my patients to have as much a varied diet as possible. Focusing less on foods being inherently “bad” or “good” and more on how food makes us feel, how food nourishes us, and how to build better gut resilience.
Contact me if you have questions about the different testing options for food allergies, sensitivities, and intolerances! Let’s find what bugs your guts!
Dr. Randi Brown, ND