Table of ContentsView AllTable of ContentsCommon CausesGastrointestinal DiseaseLifestyle Risk FactorsCommon Trigger Foods
Table of ContentsView All
View All
Table of Contents
Common Causes
Gastrointestinal Disease
Lifestyle Risk Factors
Common Trigger Foods
“Food intolerance” is sometimes confused with “food allergy.” However, the two terms should not be used interchangeably. A food intolerance mainly concerns digestion and is usually not life-threatening. In contrast, a food allergy involves the immune system and has the potential to lead to a serious and even life-threatening reaction.
This article will discuss common causes and risk factors associated with food intolerance.
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Genetics
While research has linked genetics with food allergies, less is known about its relation to food intolerance.However, some metabolic food disorders such aslactose intolerancecan be inherited. Lactose intolerance is considered an inherited deficiency of the enzyme lactase.
People with Asian, African, and Native American heritage are more prone to lactose intolerance than other populations.
Lack of Digestive Enzymes and Enzyme Defects
Some food intolerance stems from a lack of digestive enzymes.For example, a person with lactose intolerance often lacks enough of the digestive enzyme lactase. Lactase breaks down lactose commonly found in dairy products such as milk.
Non-Celiac Gluten Sensitivity
Gluten intolerance is often confused withCeliac disease, but they are not the same. A person with gluten intolerance experiences gassiness, bloating, or diarrhea after consuming foods like wheat, barley, or rye. In contrast, Celiac disease is an inherited autoimmune condition that causes damage to the small intestine.
Intolerance to Chemicals in Foods and Additives
There are many chemicals in the foods we eat. Although many people do not have difficulty digesting chemicals found in food, some people do.
While the cause is not completely understood, the following food chemicals are believed to cause unwanted gastrointestinal symptoms in some people:
Toxins and Food Poisoning
Some foods have natural toxins or chemicals that can cause toxic effects and lead to symptoms similar to a food intolerance.
Toxins and bacteria in foods like mushrooms, potatoes, and spoiled fish are among the most common toxic food intolerances.
Food intolerance appears to be more common in those with underlying digestive disorders. According to one study of people withIBS, 84% reported symptoms of intolerance to at least one food product. The most common food intolerance reported was to dairy products, beans, lentils, and histamine-releasing foods such as milk, wine, and beer.
Additionally, people withinflammatory bowel disease(IBD) are likely to also have a food intolerance. In a survey given to patients with IBD, an estimated 66% withCrohn’s disease(inflammation found anywhere in the wall of the digestive tract) and 64% of patients withulcerative colitis(inflammation of the lining of the large intestine) reported food intolerance. Common foods causing intolerance in these groups include chocolate, artificial sweeteners, fats, and dairy.
Research shows the late introduction of solids in an infant’s diet may also cause a food intolerance or allergy to develop later in life.
Trigger foods commonly associated with food intolerance include:
Summary
There are several causes of food intolerances, including enzyme deficiencies, problems processing certain chemicals, and sensitivities to certain additives in foods. Having underlying gastrointestinal diseases is also associated with food intolerances.
If you have a reaction to a certain food after eating it, have a discussion with your healthcare provider to determine what is causing your symptoms.
A Word From Verywell
Food intolerance can be challenging to diagnose. Knowing the causes and risk factors can help you better understand why you may be experiencing difficulty digesting certain foods.
Because symptoms of food allergies and food intolerance often overlap, it’s important to speak with your healthcare provider to discuss your symptoms and get a diagnosis. Healthcare providers who specialize in food allergies and food intolerance can help youdevelop a treatment planto minimize unpleasant reactions.
16 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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