Skin and laboratory tests for allergy to foods are not always conclusive or reliable. They need to be considered in the context of a detailed history of symptoms. Exclusion dieting, followed by challenge testing – eating a food to see if you react – is the most reliable method of testing for both food allergy and all types of food intolerance.
One specific form of food intolerance, which reproduces the symptoms of allergy and responds to treatment with anti-histamines, is called ‘false food allergy’. It can be detected by modified laboratory tests for allergy. Certain foods are known to cause false food allergy (i.e. peanuts, beans, pulses, wheat, egg white, shellfish, pork, fish, chocolate, tomatoes and strawberries) and other foods are suspected of causing it (i.e. buckwheat, mango, mustard, papaya, raw pineapple, sunflower seeds). If you have classic allergic symptoms caused by any of these foods, respond to antihistamine treatment, but have negative results to tests for allergy, false food allergy may be the cause.
Food intolerance caused by specific chemicals found naturally in certain foods can only be confirmed by exclusion dieting. Some foods contain chemicals that have effects directly on the body, such as histamine, other vasoactive amines and caffeine. Histamine is found naturally in fermented foods, cheeses, well-ripened foods such as salamis and sausages, and fish of the mackerel family that has been kept too warm. Other vasoactive amines are found in cheeses, fermented and pickled foods, yeast extract, chocolate, bananas, avocados, wine and citrus fruits. Caffeine is found in tea, coffee, chocolate, cola drinks and some painkillers. For a full description of this kind of intolerance.
Exclusion dieting will also help identify known enzyme defects that can cause food intolerance and specific symptoms, or coeliac disease, a form of wheat and gluten intolerance. A specialist doctor will be able to identify such defects readily from your pattern of symptoms.
Hyperactivity in children has been linked to enzyme defects and food intolerance.
People with food sensitivity often exhibit some identifiable traits of character or behaviour. While not precisely symptoms, these are strong indicators of sensitivity.