What is the difference between food allergies and food intolerances?

Food allergy produces an immediate IgE-antibody reaction with symptoms such as rashes, sneezing, hayfever and breathing difficulties. Food intolerance is a delayed IgG-antibody reaction producing symptoms up to 3 days after eating a particular food making it more difficult to identify the cause.

If I know I have a food allergy, why is the food intolerance negative for the same food?

It is important to understand the tests measure two different things, and it is quite possible for the results to be different. If you have been avoiding a food because of a known allergy, chances are that the food intolerance will be normal for this food. This does not mean it is okay to eat that food, you should continue to avoid this food.

Are these tests suitable for children?

We recommend a lower age limit of 2 years and any dietary changes should be under the supervision of a qualified health practitioner.

Why do high IgG antibody levels cause symptoms?

When a food causes the body to produce high levels of IgG then these antibodies combine with the protein in the food to form an ‘antigen-antibody complex’. These complexes are usually eliminated by other cells in the immune system. However, if the immune system is overloaded, these insoluble molecules become deposited in tissues within the body, causing chronic inflammation and the subsequent production of symptoms.

Is it possible to have high IgG levels and not experience symptoms?

Yes, some people do have high IgG levels to certain foods but do not have any symptoms at all. This is possibly due to their immune system being extremely efficient at clearing away the antigen-antibody complexes before they have chance to be deposited in the tissues and cause a problem.

Will any drugs affect the results?

Immunosuppressants which are generally given following an organ transplant will reduce the immune system’s ability to generate antibodies. High doses of steroids will also affect antibody production. If you are in any doubt, please consult your GP.

Why does the Food Detective not test for sugar or alcohol?

Food intolerance is caused by the presence of proteins and the antibodies directed against them. Sugar and alcohol are carbohydrates and do not provoke an antibody response.

What do I do if the test shows positive to any foods?

We suggest you eliminate these foods from your diet for 3 months, replacing them with healthy alternatives. After this time you should be able to reintroduce them slowly, one at a time, to avoid re-occurrence of symptoms.

What do the borderline foods mean?

The borderline foods are slightly above the normal values and ideally should be reduced to a minimum in your diet. Therefore, we recommend that you rotate those foods showing a borderline result, once every 4 days if possible.

I have a lot of positive results, how do I cut out everything?

If you have a lot of positive results, it can be a very daunting task trying to cut out everything whilst maintaining a nutritionally well balanced diet. In these cases, we recommend you visit a nutritionist who will help you to avoid the foods with a strong positive response, and to rotate the foods with a lower positive result.

Isn’t it dangerous to cut out whole food groups?

You do have to be careful when changing your diet which is why we recommend that you consult a health practitioner for dietary advice.

Do I have to avoid these foods for the rest of my life?

No. Once you have avoided those foods for at least 3 months, and you have noticed an improvement in your symptoms, then you can start to gradually introduce the foods back into your diet. You should introduce one food at a time, with an interval of 4 days before trying another food. If you do not notice the return of any symptoms, then you can continue to include that food in your diet on an occasional basis. You may find a food and symptom diary useful whilst re-introducing foods. If you do not notice any improvement after 3 months, then you can assume that this food is not responsible for your symptoms.

Do I have to eliminate that particular food completely from my diet in order to reduce my symptoms, or can I still have a little occasionally?

The most effective course of action is to eliminate the food completely. As long as exposure is maintained, antibodies will continue to be produced and the immune system primed to react. Exposure to foods of the same food family should also be avoided.

Do I need to have a re-test after a few months?

Most people do not need to have a re-test, but if you would like another test we usually advise a period of 12 months in between tests. If your symptoms have improved and you have been able to successfully re-introduce the foods, then a re-test is unnecessary.

I have been told to eliminate a particular food from my diet, but have not eaten it for years, why do I have a positive result?

This is because either a) you have eaten that food hidden in other foods (it is very important to check ingredients labels carefully); or b) you have eaten foods within the same food family and these are causing antibody production.

I know that I have a reaction to wheat and have been avoiding it, but it did not show up in the test, why?

If you have been avoiding a particular food for a few months, it is possible that antibody levels to the food concerned have reduced to a level undetectable by the test.

If I test positive to gluten or wheat, does that mean I have Celiac Disease?

Celiac Disease is an intolerance to gluten that is found in wheat, rye and barley. It affects approximately 1 person in 1000 in North America and is a life-long inflammatory condition of the intestinal tract. A positive IgG reaction to gluten is not confirmation of Celiac disease. For confirmation of Celiac Disease you should consult with your health care practitioner who may order screening tests tissue Transglutaminase IgA and Deamidated Gliadin IgA/IgG. Confirmation is usually done by performing a bowel biopsy.

If cow’s milk comes up positive, does that mean that I am lactose intolerant?

No. Lactose intolerance is the inability to digest lactose, the major sugar found in milk. It is caused by a shortage of the enzyme lactase, which is produced by the cells that line the small intestine. A positive reaction to cow’s milk is a reaction to one or more of the proteins in milk.

What are the main proteins in milk?

The total protein component of milk is composed of numerous specific proteins. The primary group of milk proteins are the caseins. All other proteins found in milk are grouped together under the name of whey proteins. The major whey proteins in cow milk are beta-lactoglobulin and alpha-lactalbumin.