Food Intolerance

Symptoms that are related to eating a specific food

  • Age, gender, genetics, and lifestyle are not significant factors

If you develop troublesome symptoms such as stomach ache each time you eat a particular food, you may have food intolerance. The cause of food intolerance is usually unknown, although in some cases there is a definite abnormality, such as an enzyme deficiency (see Lactose intolerance). Food intolerance is different from a food allergy, in which the immune system reacts inappropriately to a specific food.

What are the symptoms?

The symptoms of food intolerance vary among individuals. Symptoms are usually related to a particular type of food, such as milk or wheat flour. They may occur within minutes or hours of eating and include the following:

  • Nausea and vomiting.

  • Abdominal pain.

  • Diarrhoea.

Some people develop other symptoms, such as aching muscles or headaches.

What might be done?

In most cases of food intolerance, the diagnosis is based on your symptoms. Tests may then be performed to exclude other possible conditions. In some cases, endoscopy (see Upper digestive tract endoscopy) may be carried out to examine the digestive tract with a flexible viewing tube and to look for evidence of an intestinal disorder such as coeliac disease. During the procedure, a small sample of tissue may be taken from the intestinal wall for examination under a microscope.

Often, the only way to diagnose food intolerance is by an exclusion diet, in which the suspect food is excluded from your diet for a period of time to see if there is an improvement in your symptoms. The food is later reintroduced, and you are monitored to see if your symptoms worsen. An exclusion diet, especially one for a child, should be undertaken only under the supervision of a doctor and a dietitian because restricted diets can cause vitamin and mineral deficiencies.

Once the cause of your intolerance has been identified, you should avoid eating foods that aggravate the problem. You will probably need to consult a dietitian, who will advise you on a diet that provides all the nutrients you need.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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