Food Hypersensitivities

Dr Cornelia Botha and Dr Tanith Davidson take food hypersensitivities into consideration when treating various illnesses in their practice and have compiled the below article. To make an appointment with either Dr Cornelia Botha or Dr Tanith Davidson please contact their receptionist by visiting the contact page.

Please note: We would like to stress that the IgG food hypersensitivities referred to in this article are IgG3 and not IgG4 reactions. Testing for IgG4 food reactions has no usefulness according to scientific research studies, whereas IgG3 testing does. Misinformed doctors that criticize IgG food testing mistakenly believe that IgG4 testing is being done, but this is not the case. It is IgG3 testing that forms the basis of IgG food intolerance testing.

IgG3 mediated reactions to food

Human beings are dependent on food to provide nutrients for life and health. Most people also interact with food because it is pleasurable. Sometimes certain foods can make us feel unwell. Often we are unaware that some of the foods we consume are contributing to our symptoms or illnesses. In some cases foods plays a very big role in the disease process and other times it merely aggravates the problem.

Sometimes the role that food plays in disease is related to an immune system reaction, although this is not always the mechanism. One of the best known and certainly the most common means of testing for the role of food in a patient’s symptoms and disease is IgE testing, however, IgG3 testing has also been researched for its ability to detect the connections between diet and disease. IgG3 reactions have been referred to as food intolerance, but the more accurate term is food hypersensitivity reaction.

In cases of hypersensitivity reactions patients seem to suffer the consequences the food they have consumed for some time after the fact; sometimes starting up to 3 days later and continuing for as long as 4 weeks in some cases. This makes pinpointing the food culprit almost impossible, given the fact the other foods have been consumed during the period before the symptoms develop. This is where IgG3 testing can be very helpful.

IgG3 testing is currently a very hotly debated topic among medical professionals. Some practitioners believe that there isn't enough evidence to support its use to assist in determining whether or not food is playing a role in a patient's symptoms. Despite this contention, medical scientists have continued to study the connection between food IgG3 immune components (i.e. antibodies) and various diseases.

This article serves to create awareness about the research that has been published in various reputable medical journals regarding the subject of IgG3 testing as an approach to a number of diseases. To date asthma, eczema, irritable bowel syndrome (IBS), functional dyspepsia, migraine & migraine-like headaches, crohn’s disease (a severe inflammatory bowel disease) and juvenile obesity have been investigated for their association with food IgG3 antibodies.

In addition to this body of published research, many patients report that they benefit from IgG3 guided food avoidance in a number of additional diseases, which have not yet benefited from the scrutiny of medical research. This is where many medical professionals get very upset. They take great exception to anyone (whether doctors or patients) reporting on this since they are concerned that it might mislead patients and others practitioners, given the current lag in research evidence for diseases other than those listed here.

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Most doctors check only IgE antibodies (i.e. immediate type allergy) when searching for a cause of a patient symptoms that are associated with foods. However, Berrens & Homedes (1991) examined blood samples of human patients with immediate type allergy for both IgE and IgG3 antibodies to several of the common food allergens. Their research found a statistically significant correlation between IgE and IgG3 in test results. They concluded, “The data indicate that immune stimulation in atopic (allergic) individuals is not restricted to the IgE isotype, but equally affects the IgG3-producing antibody systems.”

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Alpay and co-workers (2010) conducted the first randomised, cross-over study in migraine sufferers, showing that diet restriction based on IgG3 antibodies is an effective strategy for reducing the frequency of migraine attacks. Mitchell et al (2011) went on to study the effect of such a strategy on those who suffer from migraine-like headaches. It was concluded that testing for IgG3 food antibodies with subsequent diet elimination advice significantly reduced the number of migraine-like headaches.

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Shakib and colleagues (1986) discovered the association between raised serum levels of IgG3 antibodies to milk proteins and eczema. More recently, Calderon and co-workers (2010) investigated the possibility of other food-specific IgG3 antibodies being associated with eczema. These researchers chose to look into the presence of beef-specific IgE, IgG3 and IgA antibodies in sera from patients with asthma, gastrointestinal disorders and skin allergies. All of these antibodies were significantly increased in this patient group. The authors noted, “Remarkably, IgG3 isotypes were significantly detected, even in the absence of IgE, in the three allergic conditions.”

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Zuo et al (2007) found that serum IgG3 antibody levels to some common foods are increased in IBS and functional dyspesia patients compared to those who do not struggle with these diseases. Yang & Li (2007) confirmed this and concluded that there is value in treating IBS by eliminating the allergic foods according to the serum level of food-specific IgG3 antibodies.

In 2012 Guo and colleagues did a 12 week intervention trial along these lines. Food-specific IgG3 antibodies were identified in 50.65% of the study patients suffering from irritable bowel syndrome with diarrhoea (D-IBS) compared with 15.38% of those patients that do not suffer from this disorder. For 12 weeks following the testing, these patients consumed diets that excluded the identified foods. After 4 weeks' dietary therapy, most symptoms of D-IBS had improved. By 12 weeks, all symptom scores had decreased significantly compared with the baseline scores. The 12-week food-specific exclusion diets resulted in significant improvements in abdominal pain (bloating level and frequency), diarrhoea frequency, abdominal distension, stool shape, general feelings of distress and total symptom score compared with baseline in patients with D-IBS.

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Crohn's disease is a severe type of inflammatory bowel disease in which the body's immune system attacks the gastrointestinal tract. Bentz and co-workers (2010) report that their findings support nutritional interventions based on circulating IgG3 antibodies against food antigens, since this improves stool frequency. Uzunısmaıl et al (2012) confirmed the benefit of such testing. They found that foods with raised IgG3 antibody levels and food additives can provoke symptoms and may stimulate the inflammation in patients with Crohn's disease. These authors recommended a diet that restricts foods with raised IgG3 antibody levels, since this may be beneficial in the medical treatment of crohn’s disease.

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Wilders-Truschnig (2008) published evidence that obese children have significantly higher IgG3 antibody values directed against food antigens than normal weight children and concluded that anti- food IgG3 antibodies are tightly associated with low grade systemic inflammation.

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Is food IgG3 testing and guided food elimination proven? All we can do is to look to the research that has already been conducted and published in respected medical journals. As with all medical research, given enough time (unfortunately, sometimes many years), a thorough study is made of a subject. Conservative medical professionals would ask patients to wait for evidence of the reliable connection between additional diseases and food IgG3 antibodies. Their primary concern is that patients unnecessarily part with their money and deprive themselves of certain foods when doing this test as a means of investigating diseases other than asthma, eczema, irritable bowel syndrome (IBS), functional dyspepsia, migraine & migraine-like headaches, crohn’s disease (a severe digestive disease) and juvenile obesity, all of which have published research to support to the benefit of IgG3 testing.

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Most importantly, it should be noted that the approach to investigating and treating the above mentioned illnesses, and other illnesses where food / diet appears to be implicated, should not focus solely on IgG3 testing and the indicated food avoidance. IgE and IgG3 reactions are not the only ways in which food / diet can cause and aggravate disease. A thorough consultations combined with additional investigations may be required depending on the specific disease in question. Furthermore, various therapies used in conjunction with diet modification should be employed for the best results.

To learn more about having the IgG3 test done click here.

To download a full document on food and health, including information from all links in this section, as well as the references for this article right click here.

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To make an appointment with either Dr Cornelia Botha or Dr Tanith Davidson please contact their receptionist by visiting the contact page.