Food intolerance is much more common than food allergy. But most of the time onset of symptoms is usually slower and may be delayed by many hours after eating the offending food. The symptoms may also last for several hours, even into the next day and sometimes longer. Intolerance to several foods or a group of foods is not uncommon, and it can be much more difficult to decide whether food intolerance is the cause of chronic illness, and which foods or substances may be responsible.
Causes of Food Intolerance:
- Enzymes help with the breakdown of natural substances found in certain foods. If these enzymes are missing, or in short supply, then eating the food can cause symptoms because part of the content of the food cannot be properly dealt with by the body.
- Certain foods such as caffeine in coffee, tea, and chocolate, or amines in certain cheeses contain naturally occurring chemicals that have an affect on the body. Some people seem to be more affected than others by these natural substances in the food.
- A number of foods contain naturally occurring substances that can exert a toxic effect causing symptoms of vomiting and diarrhoea. In cases such as kidney beans or chick peas that are undercooked, there are aflotoxins, which cause these symptoms.
- Some foods containing histamine naturally and others (such as certain fish that are not fresh and have not been stored properly) can develop a build-up of histamine in their flesh as they age. In certain people, this histamine occurring naturally in the food can cause symptoms when the food is eaten; typically, rashes, stomach pains, diarrhoea and vomiting and in some cases symptoms that can mimic anaphylaxis.