The difference between allergy and intolerance

Physical reactions to certain foods are common mostly due to food allergy or intolerance.

Food allergy and food intolerance are actually two quite distinct diseases, confused, probably, because of some common symptoms. The two terms allergy and intolerance indicate two different ways the body reacts to foreign substances. Intolerance refers to the abnormal reaction of the body to a foreign substance that is not mediated by the immune system. Allergy refers to the abnormal immune response that is expressed by producing IgE; it can cause severe symptoms and lead to anaphylactic shock. Food allergies are most common in the first 3 years of life. However, they can occur at any age. Most allergic reactions occur to relatively few foods: cow's milk, egg, soy, wheat, peanuts, tree nuts, fish and shellfish. In children, the most common food allergy is to cow's milk, followed by egg allergy and peanut allergy.

Other serious conditions can cause similar symptoms to a food intolerance but need special treatment. Celiac disease is an autoimmune disorder triggered by eating gluten. IBS is a common condition that affects the digestive system, and symptoms can be triggered by the presence of certain foods in the diet.

Is food sensitivity the same as intolerance?

After eating certain foods, many people experience symptoms that are not caused allergies, food intollerance or celiac disease. These are called food sensitivities. Although the exact mechanisms of what causes a food sensitivity to occur are not well understood, exposure to certain foods can trigger an immune reaction that generates a multitude of symptoms. These are not life-threatening, but can be disruptive and unpleasant, and may include stomach pain, joint pain, fatigue, rashes, and brain fog. Non-celiac gluten sensitivity is an example of a food sensitivity. Identifying sensitivities involves an elimination diet, removing and gradually reintroducing potential culprits to improve the quality of life. Sensitivities can change over time, allowing for the reintroduction of problematic foods to test tolerance levels. Consulting a physician or a dietitian is advisable for guidance during this process.