Food Detective Professional Test

Frequently Asked Questions

What is an IgG?

IgG stands for Immunoglobulin (type G). Immunoglobulins are a class of proteins that function as antibodies produced by the immune system in response to foreign bodies entering the body. There are several different types of immunoglobulins with IgA, IgE, IgG, IgM being the most well-known.

Why do foods cause an IgG response?

Generally, foods are broken down during digestion into their component parts e.g. amino acids, glycerides etc. These pass harmlessly through the gut into the bloodstream. However, occasionally small fragments of partially digested or undigested foods are able to pass through the gut wall into the bloodstream where they are recognized by the immune system as being ‘foreign’. The immune system responds by making IgG antibodies to these foods.

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, where they may cause chronic inflammation and the subsequent production of symptoms.

Why test for IgG antibodies to foods?

The efficacy of a diet based on the measurement of IgG antibodies specific for food components has been demonstrated in a number of conditions, both in independent studies and clinical practice. Excellent results have been obtained in patients with migraine, IBS and obesity.

What should be considered before testing - Can I take the test if I am pregnant?

A food intolerance test is not recommended during pregnancy as the immune system is suppressed. However, 4-6 weeks after giving birth should be ok.

What should be considered before testing - What is the lower age limit for testing?

Cambridge Nutritional Sciences (CNS) existing policy for a lower age limit on testing for IgG food antibodies is that we do not recommend testing on children under the age of 2 years. We base this on the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition Guidelines for the Diagnosis of Coeliac Disease 2012, which states that there is a possibility of false negative results occurring in infants younger than 2 years of age. This related to the fact that the infant gut is more permeable than that of an adult coupled with immature mucosal immunity that is still in the learning and development stage. We have used this criterion as antibody measurements in Coeliac Disease are comparable to food IgG measurements used in our food intolerance tests. However, we are aware that there are in fact no published guidelines that specifically indicate a minimum age for testing for such IgG antibodies, for example the guidelines for testing for coeliac antibodies indicate that such testing can be performed any time after the introduction of gluten into the diet. Therefore, where such requests are received from a statutory regulated professional the decision of when and what tests to perform will remain the responsibility of the requesting clinician.

What should be considered before testing - Is there any medication that I should avoid when taking a food intolerance test, due to its potential effects upon the results?

Customers should avoid the use of immunosuppressant medication if possible if performing these tests, as they may have an impact upon the results. Please refer to the medication datasheet in the “Support” section for further details.

How does the test work?

The reaction tray is imprinted with food protein extracts. A finger prick blood sample (50µl) is diluted and added to the tray. In subsequent steps the use of detector and developer solutions enables the identification of the presence of food antibodies through the appearance of one or more blue spots on the tray. The darker the spot, the higher the concentration of IgG antibodies detected to that specific food. Reference to the food layout plan allows the foods causing antibody production to be identified.

Do you need to re-introduce foods before taking a FoodPrint or Food Detective test – if so, how long for?

In general we recommend that you follow your normal diet, so that the test will reflect what you usually eat. However, if you have specifically avoided a food for more than three months e.g. cow's milk, which used to be part of your normal diet and you would like it tested, we would recommend it is reintroduced. The recommendations are to reintroduce the food for 1 week eating a normal portion of that food at least once daily before taking your blood sample. If symptoms occur once the food is re-introduced, we recommend that you discontinue that food and conclude you are still intolerant to it.

Do I have to fill the micro-pipette all the way to the black line?

Yes, in order to produce a valid test result the micro-pipette must be filled to the black line (50μl).

What are the sample requirements and test turnaround?

A pin-prick blood sample is required. Results are displayed within 40 minutes.