Scientific Studies

Studies regarding the removal of IgG
reactive foods from the diet.

Smartblood Laboratories detect food intolerances by measuring IgG antibody reactions using the ELISA method, a globally established technique for laboratory analysis that is over 40 years old and universally accepted as reliable and trustworthy. The Smartblood service is based upon testing for IgG antibodies, and the assertion that a positive result indicates a trigger food that causes an inflammatory response leading to a symptom.

There are many studies within the scientific community that support our case for this – those that are summarised below are but a handful 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.

Our laboratory is also involved in a number of research projects, both those initiated by ourselves, and those initiated by other institutions and organisations where we are a research partner. Some projects are entirely laboratory based, while others encompass both clinical and laboratory-based aspects.

Atkinson, Sheldon, Shaath, et al (2003) – Food elimination based on IgG antibodies in irritable bowel syndrome: a randomised controlled trial.

Introduction – 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 immunosorbant assay test) or a sham diet excluding the same number of foods but not those to which they had antibodies.

Summary – 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 ELISA test for the presence of IgG antibodies to these foods.

Lewis et al., (2012) – Eliminating Immunologically-Reactive Foods from the Diet and its Effect on Body Composition and Quality of Life in Overweight Persons.

Introduction

120 subjects over the age of 18 took part in a study, involving elimination of their IgG reactive foods for 90 days.

Summary

Those who eliminated their IgG reactive foods from their diet experienced reductions in weight, BMI, waist & hip circumference. Subjects also saw improvements in all quality of life measures after 90 days.

Lewis, J.E., Woolger, J.M., Melillo, A., Alonso, Y. and Rafatjah, S., 2012. Eliminating Immunologically-Reactive Foods from the Diet and its Effect on Body Composition and Quality of Life in Overweight Persons. J Obes Weig los Ther, 2(112), p.2.

Dixon HS. (2000) – Treatment of delayed food reactions based on specific immunoglobulin G testing

Introduction – Conducted by Hamilton Dixon MD in 2000, this study focused on patients that had a history of suffering from a variety of symptoms, including Fatigue (and fatigue after meals, Diarrhoea, Migraines and Itchy Skin. All patients had been unable to find the route of their problem/s using conventional methods.

Summary – 114 patients in total were tested for food sensitivities using a food specific IgG antibody test. Of the 114 initial subjects, 80 completed the study by following an elimination diet based on their IgG reactive foods. Upon elimination of reactive foods, subjects showed significant improvements in their previously reported symptoms. In subjects who reported having symptoms, the following improvements were observed, 71% of subjects realised a 75% or greater improvement in their condition/s, half of the study group realised 90% or more relief from their symptoms and perhaps most importantly, the 15 patients that did NOT eliminate their reactive foods, experienced no relief in their symptoms.

Bentz et al. (2010) – Clinical relevance of IgG antibodies against food antigens in Crohn’s disease: a double-blind cross-over diet intervention study

Introduction – 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.

Summary – 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.

Bentz, S., Hausmann, M., Piberger, H., Kellermeier, S., Paul, S., Held, L., Falk, W., Obermeier, F., Fried, M., Schölmerich, J. and Rogler, G., 2010. Clinical relevance of IgG antibodies against food antigens in Crohn’s disease: a double-blind cross-over diet intervention study. Digestion, 81(4), pp.252-264.

Rees et al. (2005) – A prospective audit of food intolerance among migraine patients in primary care clinical practice.

Introduction – This prospective audit was set up to investigate whether migraine sufferers have evidence of IgG-based food intolerances and whether their condition can be improved by the withdrawal from the diet of specific foods identified by intolerance testing. Migraine patients were recruited from primary care practices and a blood sample was taken. Enzyme-linked immunosorbent assays (ELISA) were conducted on the blood samples to detect food-specific IgG in the serum. Patients identified with food intolerances were encouraged to alter their diets to eliminate appropriate foods and were followed up for a 2-month period

Summary – This investigation demonstrated that food intolerances mediated via IgG may be associated with migraine and that changing the diet to eradicate specific foods may be a potentially effective treatment for migraine. Elimination of food that caused high IgG response lead to 30% of subjects reporting benefit to migraine symptoms after 1 month and 40% after 2 months. 60% subjects who reintroduced their reactive foods suffered onset of migraine symptoms.

Alpay et al (2010) – Diet restriction in migraine, based on IgG against foods: A clinical double-blind, randomised, cross-over trial.

Introduction – It is well-known that specific foods trigger migraine attacks in some patients. We aimed to investigate the effect of diet restriction, based on IgG antibodies against food antigens on the course of migraine attacks in this randomised, double blind, cross-over, headache-diary based trial on 30 patients diagnosed with migraine without aura. Following a 6-week baseline, IgG antibodies against food antigens were detected by ELISA. Then, the patients were randomised to a 6-week diet either excluding or including specific foods with raised IgG antibodies, individually.

Summary – Determination of specific IgG to a large number of foods is an ideal tool to detect individually suspected food and enables a modification of nutritional habits in order to prevent chronic inflammation and onset of migraine in sensitised patients. This is the first randomised, cross-over study in migraineurs, showing that diet restriction based on IgG antibodies is an effective strategy in reducing the frequency of migraine attacks.

Alpay, K., Ertaş, M., Orhan, E.K., Üstay, D.K., Lieners, C. and Baykan, B., 2010. Diet restriction in migraine, based on IgG against foods: a clinical double-blind, randomised, cross-over trial. Cephalalgia, 30(7), pp.829-837.

Karakuła-Juchnowicz et al., (2017) – The role of IgG hypersensitivity in the pathogenesis and therapy of depressive disorders.

Introduction

There is now an increasing amount of reports on the gastrointestinal tract and its role in depression.

Summary

Where increased IgG concentrations to foods were found, the implementation of an elimination or rotation diet could be an effective method of reducing inflammation, thought to be a key cause of depressive disorders

Depressive disorders may be linked to IgG food sensitivities, but further studies are required to confirm this theory.

Karakuła-Juchnowicz, H., Szachta, P., Opolska, A., Morylowska-Topolska, J., Gałęcka, M., Juchnowicz, D., Krukow, P. and Lasik, Z., 2017. The role of IgG hypersensitivity in the pathogenesis and therapy of depressive disorders. Nutritional neuroscience, 20(2), pp.110-118.

Lee and Lee (2017) – Alterations of Food-specific Serum IgG4 Titers to Common Food Antigens in Patients with Irritable Bowel Syndrome.

Introduction

32 Patients diagnosed with IBS and 32 health controls were tested using and IgG antibody test.

Summary

Patient with IBS had significantly higher IgG antibody reactions than the control group.

Serum antibody levels to common foods are abnormally elevated in IBS patients.

Lee, H.S. and Lee, K.J., 2017. Alterations of Food-specific Serum IgG4 Titers to Common Food Antigens in Patients With Irritable Bowel Syndrome. Journal of neurogastroenterology and motility, 23(4), p.578.

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.

Introduction

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.

Summary

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

Virdee, K., Musset, J., Baral, M., Cronin, C. and Langland, J., 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. Global advances in health and medicine, 4(1), pp.62-66.

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If you think that food intolerance may be responsible for your symptoms then we believe that our easy-to-complete tests could help you. Find all your food intolerances at once with a full Smartblood test.

The full Smartblood test is a complete program and is a great way to discover all of your food sensitivities and take control over your own personal trigger foods.

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