When it comes to food sensitivities, people often get confused between food allergy, food sensitivity and food intolerance. Although they are very similar when it comes to symptoms, there are differences between them that you should be aware of.
Food Allergy
A food allergy is your body’s immune system response to specific foods, triggering a histamine reaction. Even a tiny amount of the allergy-causing food can trigger signs and symptoms such as digestive problems, hives or swollen airways. Allergic reactions are often mild, but potentially severe symptoms like anaphylaxis (an acute life-threatening allergic reaction to an antigen, e.g. a bee sting, to which the body has become hypersensitive) can occur. Symptoms of a food allergy can affect different parts of your body at the same time. Most people with food allergies are aware of their allergies based on the reactions and immediate response times when eating certain foods.
Food allergy symptoms include eczema flare, redness of the skin, itchy mouth or ear, nausea or vomiting, diarrhea, stomach pain, nasal congestion, runny nose, or trouble breathing, hives (reddish, swollen, itchy areas on the skin), swelling of the lips, face, tongue, and throat, dizziness, lightheadedness, or fainting, anaphylaxis.
Food allergies include: tree nut allergy (e.g. walnuts, cashew, pecans, almonds), soy allergy, corn allergy, egg allergy, wheat allergy, garlic allergy, milk allergy (including lactose), alpha-gal allergy (meat or mammalian meat allergy MMA), peanut allergy, fruit allergy, fish allergy (e.g., bass, flounder, cod), shellfish allergy (e.g., crab, lobster, shrimp), mustard allergy, sesame allergy, lupin allergy, molluscs allergy (e.g., mussels, oysters, snails, squid).
When you have a food allergy, your immune system mistakenly identifies a specific food or a substance in food as something harmful. In response, your immune system triggers cells to release an antibody known as immunoglobulin E (IgE) to neutralize the allergy-causing food or food substance (the allergen).
The next time you eat even the smallest amount of that food, IgE antibodies sense it and signal your immune system to release a chemical called histamine, as well as other chemicals, into your bloodstream.
Food Sensitivity and Food Intolerances
The difference between a food allergy and food sensitivity or intolerance is the body’s response. Unlike a food allergy, the symptoms can be delayed for a few days after ingesting the trigger food. If you have a food sensitivity or intolerance, the reaction is triggered by your digestive system. Food sensitivities involve the inappropriate activation of the immune system upon exposure to a particular food. Food intolerance on the other hand, do not involve your immune system, but rather, an abnormal functional response to that food component. A food intolerance occurs when you lack an enzyme needed to break down a certain food, triggering a digestive response. For example, a person with lactose intolerance lack enough quantities of the enzyme lactase to break down the sugars in the milk, resulting in gastrointestinal issues. Despite having different underlying mechanisms, food sensitivities and food intolerances may express themselves with similar symptoms. Some of these symptoms include: diarrhea, nausea, bloating and gas, abdominal pain and cramping. Extra-intestinal symptoms include: fatigue, joint pain, eczema, or brain fog.

Immune mediated food sensitivities include: celiac disease, igE mediated food allergies like nut allergies, non-igE mediated allergies like Easinophillic Esophagitis, or food protein-induced enteropathies.
Non-immune mediated food intolerances include: Lactose maldigestion, Fructan intolerance, Fructose malabsorption, Caffeine intolerance, and intolerance to other fermentable carbohydrates.

Food intolerances include: eggs, soy, dairy products, corn, shellfish, gluten-containing foods (wheat, rye, barley), food additives like sulfites or artificial colour, beef, pork and lamb. High FODMAPs foods (fermentable oligosaccharides, disaccharides, monosaccharide and polyols) which are carbohydrates that are fermentable, osmotic, and poorly absorbed, resulting in digestive issues and intestinal gas buildup. Examples of FODMAPs include: cherries, dried fruit, apples, papaya, mango, sour cream, yogurt, mushrooms, cottage cheese, beans, lentils, squash, cabbage, broccoli, coffee, onions, high-fructose corn syrup, artificial sweeteners, chocolate, garlic, milk from cows, sheep or goats.

Adverse food events, such as symptoms that develop after ingesting a certain food, could be related to changes in the gut microbiota. Differences have been found in intestinal microbiota composition between healthy people and people suffering from food sensitivities. Your gut microbiota can affect how your immune system recognizes and reacts to certain foods.

Do you suspect you have a food allergy, sensitivity or intolerance? Come for your FREE one-hour consultation at Allergy Laser Clinic ($149 value) for us to access and come up with a plan to cure your symptoms. You can book online at https://allergylaser.ca/book-appointment/