Theme: iWiki Log in Register

Diff: Food Intolerances

Comparing revision #1 (2023-06-10 00:35:14) with revision #2 (2026-06-22 11:22:23).

Old	New
	'''Food intolerances''' are reactions in which a food or food component repeatedly causes symptoms, usually without the immediate IgE-mediated immune reaction seen in many food allergies. They can still be disruptive, but they are generally managed differently from allergy.

Food intolerances refer to adverse reactions to certain foods or food components that do not involve the immune system. Unlike food allergies, which are immune-mediated responses triggered by specific proteins in foods, food intolerances are typically caused by difficulties in digesting or metabolizing certain substances.
	The distinction matters because food allergy can cause anaphylaxis, while intolerance more often causes digestive symptoms such as bloating, abdominal pain, diarrhoea or constipation. Some symptoms overlap, so a careful history is needed before removing major food groups.

== Overview ==
Food intolerances are relatively common and can affect people of all ages. The symptoms of food intolerances can vary widely, ranging from mild discomfort to more severe gastrointestinal or systemic symptoms. The underlying mechanisms behind food intolerances can differ depending on the specific type.
	== Common Types ==
	Common examples include lactose intolerance, reactions to some fermentable carbohydrates, sensitivity to certain food additives, and symptoms linked to naturally occurring substances such as caffeine or histamine in some people.

== Types of Food Intolerances ==
There are several types of food intolerances, including:
	Gluten-related symptoms need careful assessment because coeliac disease is an autoimmune condition, wheat allergy is an allergy, and non-coeliac gluten sensitivity is a separate diagnosis of exclusion.

* Lactose Intolerance: This is the most well-known type of food intolerance. Lactose intolerance occurs when the body lacks an enzyme called lactase, which is needed to digest lactose, a sugar found in milk and dairy products.
* Fructose Intolerance: Some individuals may have difficulty absorbing fructose, a type of sugar found in fruits, honey, and certain sweeteners. This can lead to gastrointestinal symptoms such as bloating, diarrhea, and abdominal pain.
* Histamine Intolerance: Histamine is a compound found in various foods and is also produced by the body. In individuals with histamine intolerance, there is a buildup of histamine due to impaired metabolism, leading to symptoms such as headaches, flushing, hives, and gastrointestinal disturbances.
* Gluten Sensitivity: While not an intolerance in the strictest sense, gluten sensitivity refers to adverse reactions to gluten-containing foods that do not involve an autoimmune response (as in celiac disease) or a wheat allergy. Individuals with gluten sensitivity may experience gastrointestinal symptoms, fatigue, or other systemic manifestations.
* Food Additive Intolerance: Some people may have sensitivities to certain food additives, such as sulfites, monosodium glutamate (MSG), or artificial sweeteners, which can cause symptoms ranging from headaches to gastrointestinal disturbances.
	== Symptoms ==
	Symptoms vary by person and trigger. Digestive symptoms can include bloating, cramps, abdominal pain, wind, diarrhoea, constipation and nausea. Some people also report headaches, flushing, tiredness, skin flares, rhinitis-like symptoms or palpitations.

It is important to note that food intolerances are distinct from food allergies and should not be confused. Food allergies involve an immune response, while food intolerances typically involve difficulties in digestion or metabolism.
	Symptoms may depend on dose. A person might tolerate a small amount of a food but develop symptoms after a larger portion or repeated exposure.

== Symptoms and Diagnosis ==
The symptoms of food intolerances can vary depending on the individual and the specific type of intolerance. Common symptoms include:
	== Diagnosis ==
	Diagnosis usually starts with a medical history, symptom timing, diet pattern and other possible causes. A food and symptom diary can be useful, especially when symptoms are intermittent.

* Digestive symptoms: Bloating, abdominal pain, diarrhea, constipation, and gas.
* Skin symptoms: Rashes, hives, itching, or eczema.
* Respiratory symptoms: Runny nose, sneezing, wheezing, or shortness of breath.
* Systemic symptoms: Fatigue, headaches, joint pain, or malaise.
	For many intolerances there is no single definitive test. A supervised elimination and reintroduction plan may be used to check whether symptoms reliably improve and return. Coeliac disease and true food allergy should be considered before gluten, wheat, milk or other major foods are removed for long periods.

Diagnosing food intolerances can be challenging, as there are no definitive diagnostic tests available for many types. Healthcare professionals often rely on a combination of medical history, elimination diets, and symptom monitoring to identify potential trigger foods. In some cases, specific tests or consultations with specialists may be necessary.
	Commercial tests should be treated cautiously unless they are recommended by an appropriate clinician. Poorly supported testing can lead to unnecessary restriction and missed diagnoses.

== Management and Treatment ==
The primary treatment for food intolerances is the avoidance of trigger foods or substances. This involves identifying the specific foods causing symptoms and eliminating them from the diet. Keeping a food diary and working with a registered dietitian or healthcare professional can be helpful in creating a balanced diet that avoids trigger foods while ensuring adequate nutrition.
	== Management ==
	Management focuses on identifying triggers, reducing symptoms and keeping the diet balanced. Some people can avoid a trigger completely, while others can tolerate small amounts.

In certain situations, individuals may be able to tolerate small amounts of the trigger food or find ways to reduce symptoms through cooking techniques or enzyme supplements.
	Dietitian input can be useful where several foods are suspected, where a child is affected, where weight loss or nutritional deficiency is a concern, or where a restricted diet is being considered.

	Examples include using lactose-free dairy or lactase enzyme for lactose intolerance, adjusting fibre and fermentable carbohydrate intake for some bowel symptoms, or avoiding specific additives only when they are clearly linked to symptoms.

	== Difference from Food Allergy ==
	Food allergy can cause rapid symptoms such as hives, swelling, wheeze, vomiting, collapse or anaphylaxis after exposure to a trigger. Food intolerance usually has a slower pattern and is often dose-related.

	Someone with breathing difficulty, throat swelling, collapse, or rapidly worsening symptoms after eating should be treated as a possible emergency allergic reaction rather than a routine intolerance episode.

== See Also ==	== See Also ==
	* [[Food_Allergies]]
	* [[Coeliac_Disease]]
	* [[Lactose_Intolerance]]
	* [[Gluten_Sensitivity]]
	* [[Histamine_Intolerance]]

* [[Food Allergies]] - Learn about immune-mediated responses to specific proteins in foods.
* [[Celiac Disease]] - Explore an autoimmune disorder triggered by gluten consumption.
* [[Lactose Intolerance]] - Understand difficulties in digesting lactose, a sugar found in milk and dairy products.
* [[Gluten Sensitivity]] - Discover adverse reactions to gluten-containing foods that are not allergies or celiac disease.
* [[Histamine Intolerance]] - Learn about difficulties in metabolizing histamine, causing adverse reactions to certain foods.
	== References ==
	* [https://www.uhd.nhs.uk/uploads/services/docs/children/food-intolerance-leaflet.pdf University Hospitals Dorset NHS Foundation Trust: Food intolerance factsheet]
	* [https://www.allergyuk.org/resources/food-intolerance/ Allergy UK: Food intolerance]
	* [https://www.food.gov.uk/safety-hygiene/food-allergy-and-intolerance Food Standards Agency: Food allergy and intolerance]
	* [https://www.nhs.uk/conditions/food-allergy/ NHS: Food allergy]

	[[Category:Medicine]]
	[[Category:Food]]
	[[Category:Gastroenterology]]