Definition of Food Intolerance vs. Sensitivity

If you’re considering an elimination diet, it’s important to understand the different types of food reactions that your body may have to certain foods. There are three types of reactions: food intolerance, food sensitivity, and food allergy. These reactions can cause a variety of symptoms and health problems, and identifying and addressing them can be an important part of a functional medicine approach to healthcare. By understanding the differences between these types of reactions, you can better understand how an elimination diet can be used to identify food triggers and promote optimal health.

Food Intolerance

Food intolerance refers to difficulty digesting certain foods, which can cause symptoms such as bloating, gas, diarrhea, and abdominal pain. Food intolerances are typically caused by a lack of specific enzymes needed to digest certain foods. For example, lactose intolerance is a common type of food intolerance caused by a lack of lactase, the enzyme needed to break down lactose in milk.

Food Sensitivity

Food sensitivity refers to a delayed, non-IgE immune reaction to specific foods, which can cause a wide range of symptoms such as headaches, joint pain, and fatigue. These symptoms can occur hours or even days after eating the offending food. Food sensitivities are thought to be caused by an abnormal immune response, in which the immune system mistakenly identifies a food as a foreign invader and mounts an attack against it.

Food sensitivity is typically not an IgE response, but instead is thought to be a delayed, non-IgE immune reaction to specific foods. This type of reaction is often referred to as a Type III or Type IV hypersensitivity reaction, and is mediated by a different type of immune cell known as a T-cell or B-cell, rather than IgE antibodies.

IgG testing is sometimes used as a way to identify food sensitivities, but the use of IgG testing is not the gold standard, as it is not always a reliable or accurate measure of food sensitivity. The gold standard for identifying food sensitivities is an elimination diet followed by a controlled reintroduction of specific foods to identify triggers. However, some functional medicine practitioners do use IgG testing in conjunction with other methods to identify potential food sensitivities.

Food Allergy

Food allergy is a type of immediate, IgE-mediated immune response to specific foods, which can cause symptoms such as hives, swelling, and anaphylaxis. These symptoms typically occur within minutes to hours of exposure to the offending food. Food allergies are caused by an overreaction of the immune system to specific proteins in certain foods. Food allergies must be addressed with a doctor and completed avoided in the diet