People who have food intolerance react to chemicals which either occur naturally in food or are added to foods during processing. Different people will tolerate different amounts of chemicals and larger amounts cause stronger symptoms. The amount of the chemical which causes symptoms is called the ‘dose threshold’. Some people have a high dose threshold to all food chemicals and may never have symptoms after eating foods. Some people have a low dose threshold to food chemicals and can have unpleasant symptoms after eating foods containing a particular chemical. This type of problem is very similar to the way that some people have side effects to certain medications. More than one type of chemical may cause symptoms so a person may react to many different types of foods. Some foods contain the same chemicals and a person can react after eating a variety of these. This is because the chemical slowly builds up in the body until the dose threshold is reached. It also explains why the same food does not cause symptoms every time it is eaten. Food intolerances often run in families, suggesting a genetic predisposition. Sometimes food intolerance only affects a person after a sudden change in diet or after an illness. Natural chemicals that may cause a reaction include:
Food additives that may cause a reaction include:
* reference from the DAA Website. |