Food Sensitivity Related Conditions

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Although still controversial in mainstream medicine, food sensitivities in naturopathic medicine have been known for years to contribute to a number of different acute and chronic health concerns. 


The immune system can react to foods in a few different ways:


An IgE reaction is the classic ‘food allergy’ reaction.  It’s immediate and strong, occurring within minutes to hours of exposure, like a child having an anaphylactic reaction to peanuts. 

IgG, IgA and IgM, other components of the immune system, produce delayed-type hypersensitivity reactions that take hours to days to show up. These reactions are called 'food sensitivities,' which can be sometimes identified by an elimination diet, but usually produce more subtle symptoms than a food allergy.


As a naturopathic doctor, I can test for IgE, IgG and IgA hypersensitivity reactions to foods with various blood tests.  An allergist with a skin scratch test is looking for only IgE (immediate and severe) reactions.  Each of the immune system responses to foods causes inflammation in the body, and preoccupies the immune system as it responds to foods rather than being on the lookout for possible infectious agents.  Patients with food sensitivities (IgG, IgA or IgM mediated) often have vague inflammatory symptoms - gas and bloating, rashes, eczema or psoriasis, headaches, brain fog - as opposed to those patients with true IgE food allergies that have immediate and notable reactions.


Research to support testing the delayed-type hypersensitivity reactions of IgG and IgA (which we commonly test for in our patients at Acubalance) is starting to accumulate supporting its role in clinical practice.


In one study, 125 patients identified by an allergist as having likely food allergies were given blood tests for IgG sensitivities – all positive foods were then removed for a 6 month period.  The allergist considered the treatment a success when a minimum of 75% improvement in symptoms occurred.  In the study, of the 80 patients who completed the full course of treatment, 71% were successfully treated.  Perhaps more impressive is that there were 11 patients in this study who had food allergy symptoms that didn’t show up in the allergist’s IgE test results.  Removing the IgG food allergens successfully treated all of these 11 patients.  The allergist concluded that testing IgG food reactions is clinically useful.


There are a number of health conditions that have been linked to IgG food sensitivities in the research. Here are a few:


Irritable bowel syndrome: a 2004 British study showed that eliminating IgG sensitive foods from the diet reduced IBS symptoms, non-IBS related symptoms, anxiety/depression scores and increased quality of life scores.


Migraine: another 2004 study showed that IgG reactions may play a role in the etiology (cause) and/or treatment of migraine headaches.  A 2010 randomixed crossover tiral showed a statistically significant drop in the number of headache days during the 6 weeks IgG reactive foods were eliminated from the diet.


Weight Gain: a 2008 paper reported that obese children have significantly higher IgG antibodies to food antigens than normal weight children.  They also found that IgG antibody concentrations were strongly associated with low grade systemic inflammation.


Atopy: allergic individuals and those with atopy (eczema, asthma, other allergic symptoms) achieved 70% reduction in symptoms with elimination of IgG reactive foods in one study. 


ADHD: although no studies directly correlate elevated IgG levels to specific foods with hyperactivity in children, a few studies have shown improved child attentiveness and temperament with removal of common food allergens (wheat, dairy, oranges).


Generally speaking, removing foods from the diet that one has an IgG reaction to for a period of 6 months, in combination with a gut-rebuilding protocol, allows the body enough time to become desensitized to the allergenic food so that it will no longer respond on reintroduction of the offending food.  I test for these IgG and IgA food allergy responses in many patients when an elimination or detox diet doesn’t give us enough answers. 


Ask me about food sensitivity testing at your next appointment!


In health,


Dr. Kali MacIsaac HBSc, ND
Naturopathic Doctor