Digestive Health Irritable Bowel Syndrome Symptoms 10 Types of Food Intolerance and Their Symptoms Also known as food sensitivity (not food allergy) By Barbara Bolen, PhD Barbara Bolen, PhD Twitter Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome. Learn about our editorial process Updated on June 19, 2022 Medically reviewed by Shadi Hamdeh, MD Medically reviewed by Shadi Hamdeh, MD Shadi Hamdeh, MD, is a board-certified gastroenterologist and an assistant professor of medicine at the University of Kansas Medical Center. Learn about our Medical Expert Board Print Table of Contents View All Table of Contents Intolerance vs. Allergy Elimination Diet Foods to Eliminate Summary Frequently Asked Questions Food intolerance, also called food sensitivity, can lead to digestive symptoms such as bloating and nausea. While they can feel similar, having symptoms of food intolerance is not the same as having a food allergy. Here is a list of the most common food intolerances. You will also learn how a food intolerance is different from a food allergy, how to find out if you have a food intolerance, and what you can do if you are intolerant to a specific food. 2:14 8 Surprising Sources of Common Food Allergens Food Intolerances vs. Food Allergy Food intolerances are not the same as food allergies. While food sensitivity symptoms and food allergy symptoms can overlap, they happen for different reasons. Here are a few key differences between having a food intolerance and a food allergy. Definition of Food Allergy Food Allergies happen because of a reaction by the immune system to foods or certain parts of foods that are allergens. When the body reacts to an allergen, it releases chemicals called histamines that can cause symptoms. People with food allergies can have digestive, respiratory, and even skin symptoms. People with severe allergies can have a life-threatening reaction called anaphylaxis. Food allergies are diagnosed with blood tests that measure IgE antibodies, which are produced due to the body's immune response to certain foods. Definition of Food Sensitivity While a food allergy is an immune system response to a food, food intolerance is a problem with digesting foods. People with food intolerances can have gastrointestinal symptoms like bloating, gas, abdominal pain, and diarrhea after eating certain foods. Unlike a food allergy, food intolerance does not cause anaphylactic reactions. Identifying a food intolerance requires careful observation of cause and effect. Some people are intolerant to food additives, like flavorings, dyes, and preservatives. Food Allergy vs. Food Intolerance Food Allergy Symptoms Vomiting Diarrhea Skin rashes Trouble breathing Swelling Itching Hives Anaphylaxis Foot Intolerance Symptoms Bloating Gas Abdominal Pain Diarrhea Source: The American Academy of Allergy, Asthma & Immunology Elimination Diet's Role in Diagnosis One way to try to identify a food intolerance is to use an elimination diet that's followed by a "challenge" phase in which you re-introduce the food and assess for symptoms. While the diet can be helpful for figuring out which foods bother you, it doesn't work for everyone. Based on your symptoms, you might not be able to tell the difference between food intolerance and a food allergy. You should work with your healthcare provider to do an elimination diet. Throughout, you will want to keep a food diary, as other factors such as weather, mood, exercise, and menstrual cycles can all affect your gastrointestinal (GI) and other symptoms. If trying the diet doesn't help you and your provider figure out what is causing your symptoms, they might want to do other tests. However, food sensitivity tests are not a reliable way to pick up a food intolerances compared to using an elimination diet and food challenge. Deciding What Foods to Eliminate If you don't know which foods you can't tolerate, it usually it's helpful to start your elimination diet by avoiding foods that commonly cause the most trouble for people in general. You can choose to eliminate one food at a time, or to eliminate them all at once. 1 Dairy Products Jamie Grill / Getty Images There are two reasons why a person may have a food intolerance to dairy products: Many people are lactose intolerant. This means that they lack enough lactase, a digestive enzyme necessary to digest the lactose sugar that's present in dairy products. Dairy products contain a protein called casein. Casein may be hard to digest and can result in inflammation within the digestive system. Symptoms of Dairy Intolerance Having a food intolerance to dairy products can cause gastrointestinal and/or respiratory symptoms, as well as skin reactions. Foods to Eliminate If you choose to eliminate dairy products to see if you have a food intolerance, you would not eat: MilkCheeseButterYogurtIce creamAny product derived from the milk of cows, goats, and sheep 2 Eggs Dave Bradley Photography / Getty Images Eggs have the notorious distinction of being on the top list of allergy foods for children. However, there are also proteins within eggs that some people can't tolerate. Symptoms of Egg Intolerance If you have a food intolerance to eggs, you may have gastrointestinal symptoms like bloating, nausea, and diarrhea. Foods to Eliminate Egg whites have more of the proteins that can cause symptoms, but if you're going to include eggs on your elimination diet, it's best to avoid them completely. Once you've eliminated eggs from your diet for a period of time, you can challenge the egg yolks and egg whites separately to assess for any reactivity. If you have a food intolerance to eggs, you can avoid symptoms by following the same dietary recommendations as someone who is allergic to eggs. This can also include avoiding foods like baked goods that are prepared with an egg wash. An Overview of Egg Allergy 3 Peanuts Maximilian Stock Ltd. / Getty Images Peanuts are actually classified as legumes. They are one of the top food allergens. Even if you don't have an allergic reaction when you eat peanuts, you could be intolerant to them. Symptoms of Peanut Intolerance Food intolerance to peanuts can include respiratory or digestive symptoms. Foods to Eliminate In addition to avoiding peanuts, you'll want to cut out foods made with them like peanut butter, candies, and baked goods. 4 Shellfish Jeff Wasserman / Stocksy United Food intolerance to shellfish can happen because of proteins found in this group of marine creatures. Symptoms of Shellfish Intolerance If you have a food intolerance to shellfish you may have digestive symptoms if you eat it. However, you will not develop a life-threatening reaction that can happen with an allergy to shellfish (anaphylaxis). Foods to Eliminate To find out if you are intolerant to shellfish, you'll want to avoid: ClamsCrabsLobsterOystersScallopsShrimp 5 Gluten rzdeb / E+ / Getty Images Gluten is a protein found in barley, wheat, and rye. It must be totally avoided by individuals who have celiac disease. People with celiac disease are truly allergic to gluten. You can have a gluten intolerance instead of a gluten allergy. Some people refer to the digestive symptoms they get from eating gluten as "gluten sensitivity." Symptoms of Gluten Intolerance There is some evidence that gluten sensitivity might be the cause of irritable bowel syndrome (IBS) in some individuals. People with IBS experience a range of digestive symptoms like diarrhea, constipation, and bloating. Anecdotally, gluten is suspected to be a factor in a wide variety of health and behavioral problems. Foods to Eliminate To find out if you have gluten intolerance, you can try following a gluten-free diet where you avoid foods made with certain grains. Not all grains have gluten. Here are a few examples of grains that have gluten in them: WheatBarelyRyeSpeltFarinaKamut You'll also need to carefully check food labels because gluten can be in bread, pasta, cereals, snack bars, and crackers. Gluten is also often found in sweets, beverages, condiments, sauces, and processed meats. Symptoms of Gluten Sensitivity 6 Corn Max Oppenheim / Getty Images Corn on its own is a popular vegetable, but it's also an ingredient in a variety of foods. If you have corn intolerance, you may not be able to digest corn or have digestive upset when you eat foods made with corn. Symptoms of Corn Intolerance In research studies, corn has shown up as one of the top foods to contribute to IBS symptoms, like bowel changes, abdominal pain, and bloating. Foods to Eliminate While it can be easy to avoid corn on the cob, canned corn, and popcorn, corn is in a lot of other foods in less obvious ways. You'll need to read labels carefully and avoid foods that are made with corn products. For example, many processed foods are made with high fructose corn syrup. 7 Soy Mache Seibel, MD Soy is a popular ingredient in many recipes and can also be enjoyed on its own in the form of edamame or tofu. Soy is on the list of top allergens for children, but you can also have a food intolerance to soy. Symptoms of Soy Intolerance Anecdotally, many adults attribute their gastrointestinal IBS symptoms to eating soy-based products. Foods to Avoid Like corn, soy and its derivatives are now found in many food products. If you're eliminating soy from your diet to find out if you have a food intolerance, you'll want to avoid: TofuEdamameSoy sauceTeriyaki sauceMisoTamariTempehTextured vegetable protein You must carefully read food labels to see if it contains soy or soy ingredients. Many protein bars, frozen desserts, pasta, cereals, and meat substitutes are made with soy (for example, as soy protein). 8 Beef, Pork, and Lamb Katrina Wittkamp / Getty Images Some people are intolerant to animal meats. Food intolerance to meat might be linked to the way the livestock is reared. Conventionally raised livestock are given corn and soy as primary feed sources, as opposed to grazing on grasses in a pasture. These animals are also given hormones and antibiotics, all of which have the potential to affect the meat that you're eating. Symptoms of Meat Intolerance If you don't tolerate certain kinds of meat, you might have indigestion, nausea, and bloating when you eat them. What to Eliminate If you think that you are intolerant to meat, try looking for pasture-raised animals and do a food challenge with meats, paying attention to the way the animals were raised and fed. 9 Coffee Jonathan Kantor / Getty Images People who have a food intolerance to coffee usually experience digestive upset after having the beverage. Symptoms of Coffee Intolerance Many people report that drinking coffee stimulates their bowels. This might be a good thing for some, but for others, certain proteins and chemicals (salicylates) found in coffee may contribute to unwanted digestive symptoms. Foods to Eliminate If you're going to add coffee and coffee beverages like lattes and mochas to the list of foods to avoid on your elimination diet, you will want to wean yourself off slowly to prevent caffeine withdrawal symptoms. What Is a Caffeine Withdrawal Headache? 10 High-FODMAP Foods Diana Miller Cultura / Getty Images FODMAPs are a type of carbohydrate that are fermentable, osmotic, and poorly absorbed. Some people are not able to tolerate foods that are high in FODMAPs. Symptoms of FODMAP Intolerance High-FODMAP foods can cause digestive symptoms for some people. Research studies have found that following a low-FODMAP diet reduces IBS symptoms in approximately 75% of IBS patients. Foods to Eliminate If you think you might be intolerant to high-FODMAP foods, you can try a FODMAPs elimination diet first, then conduct a subsequent food challenge. The Different FODMAP Types for IBS Symptoms Intolerances to Food Additives Some people are intolerant to certain ingredients in a food product rather than the food itself. Preservatives, dyes, or other ingredients may be behind their symptoms. The most common food additive intolerances are food coloring, sodium benzoate, and sulfite. Summary Food intolerances are not the same as food allergies, though they can have similar symptoms. A person with a food intolerance gets digestive symptoms like gas and bloating when they eat a particular food. People with an allergy have an immune response to allergens in specific foods, and they can develop serious symptoms like trouble breathing, rashes, and even anaphylaxis. While food intolerances can be difficult to identify, they are rarely life-threatening. The best way to find out if you are intolerant to a food or an ingredient in a food product is to do an elimination diet under the guidance of your provider. Frequently Asked Questions What causes sensitivity to food? A food intolerance or sensitivity happens because a person has trouble digesting a certain food. This is different from a food allergy, which is an immune system response to an allergen in a food. How do healthcare providers test for food sensitivity? Your provider might do blood and skin tests to see if you react to certain allergens. If you don't, you might be dealing with a food intolerance instead.But the best way to find out if you have a food intolerance is to do an elimination diet. Learn More: How to Do an Elimination Diet Are at-home food intolerance test kits accurate? At-home tests to look for food intolerances or sensitivities might give you some clues about which foods are causing your symptoms, but you should confirm the results with your provider. Can you reverse food sensitivities? As with food allergies, some people grow out of food sensitivities. But there aren't any steps you can take to make this happen. You can, however, make dietary changes to mitigate symptoms. The Best At-Home Food Sensitivity Tests of 2022 10 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Gordon, B. Are Food Sensitivity Tests Accurate?. Di costanzo M, Berni canani R. Lactose Intolerance: Common Misunderstandings. Ann Nutr Metab. 2018;73 Suppl 4:30-37. doi:10.1159/000493669 Mathew P, Pfleghaar JL. Egg Allergy.In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing Patel R, Koterba AP. Peanut Allergy. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing. Alonso LL, Warrington SJ. Shellfish Allergy. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing Barbaro MR, Cremon C, Stanghellini V, Barbara G. Recent advances in understanding non-celiac gluten sensitivity. F1000Res. 2018;7. doi: 10.12688/f1000research.15849.1 Wilson JM, Platts-mills TAE. Meat allergy and allergens. Mol Immunol. 2018;100:107-112. doi:10.1016/j.molimm.2018.03.018 Barrett JS, Gibson PR. Fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) and nonallergic food intolerance: FODMAPs or food chemicals?. Therap Adv Gastroenterol. 2012;5(4):261-8. doi:10.1177/1756283X11436241 Worm, M. Q&A: Food additive intolerance. BMC Med 9, 115 (2011). doi:0.1186/1741-7015-9-115 Klasco, R. Can You Get Over a Food Intolerance?. Additional Reading Heizer W, Southern S, & McGovern S. The Role of Diet in Symptoms of Irritable Bowel Syndrome in Adults: A Narrative Review. The Journal of the American Dietetic Association. July 2009;109(7):1204-14. doi:10.1016/j.jada.2009.04.012. Mullin GE, Swift KM. The Inside Tract: Your Good Gut Guide to Great Digestive Health. New York, NY: Rodale; 2011. Shepherd S, Gibson P. The Complete Low-FODMAP Diet. New York, NY: The Experiment; 2013. By Barbara Bolen, PhD Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit