The Science

Test4 Limited detects food sensitivities by measuring immunoglobulin G (IgG) antibody reactions. We use the E.L.I.S.A. method, a globally-established technique for laboratory analysis that is over 40 years old and universally recognised as reliable and trustworthy. The Test4 service is based upon testing for IgG antibodies. A positive result indicates that a trigger food has caused an inflammatory response which would, in turn, lead to a symptom.

There are many studies within the scientific community that support our process - those that are summarised below are just a sample of published articles related to our field. As with any scientific hypothesis there will be studies that support and do not support a position, and we invite our clients to not just consider the quantitative data that is usually provided but also the qualitatively measured human experiences and benefits of eliminating an IgG reactive food from the diet.

Atkinson, Sheldon, Shaath, Et Al (2003) - Food Elimination Based on IgG Antibodies in Irritable Bowel Syndrome: A Randomised Controlled Trial.


A total of 150 outpatients with IBS were randomised to receive, for three months, either a diet excluding all foods to which they had raised IgG antibodies (enzyme linked immunosorbent assay test) or a sham diet excluding the same number of foods but not those to which they had antibodies.


A clinically significant improvement in IBS symptomatology was observed in patients eliminating foods to which they were found to exhibit sensitivity, as identified by an E.L.I.S.A. test for the presence of IgG antibodies to these foods.

Bentz Et Al. (2010) - Clinical Relevance of IgG Antibodies Against Food Antigens In Crohn's Disease: A Double-Blind Cross-Over Diet Intervention Study


In this pilot study 79 Crohn’s Disease patients and 20 healthy controls were examined for food-specific immunoglobulin G (IgG). Thereafter, the clinical relevance of these food IgG antibodies was assessed in a double-blind cross-over study with 40 patients. Based on the IgG antibodies, a nutritional intervention was planned.


A nutritional intervention based on circulating IgG antibodies against food antigens showed effects with respect to stool frequency. Significant improvement in Crohn’s disease sufferers who followed diet removing food they showed sensitivity to (food sensitivity highlighted though IgG test). A clinically significant improvement in IBD symptoms was observed in patients eliminating foods to which they were found to exhibit sensitivity.

Virdee Et Al., (2015) - Food-Specific IgG Antibody—Guided Elimination Diets Followed By Resolution Of Asthma Symptoms And Reduction In Pharmacological Interventions In Two Patients: A Case Report.


A pilot study looked at two case studies of individuals with Asthma. The two subjects were put on an elimination diet after taking an IgG food intolerance test.


Both patients demonstrated substantial relief in symptoms of Asthma after following an IgG antibody guided elimination diet.


Studies into the effects of IgG Antibodies have shown that they can influence things as varied as asthma and depression!

Test4 Sensitivity Kit


Our Full Sensitivity Test identifies the largest range of food/drink sensitivities, testing against 134 food and drink reactions it is the perfect programme to take control over your trigger foods. You also receive a 30-minute consultation with one of our nutritional therapists who can advise you on replacement foods, managing your diet and much more.