Food Allergies – are IgG tests useful?

More and more parents are coming to me with questions about food sensitivities. They wonder whether there is any real reason to take certain foods out of the diet; if they might be causing their child's troubling symptoms. They wonder about testing. They wonder about the dangers of restrictive diets.

This blog post outlines where I stand on food sensitivities and food sensitivity testing.

Food sensitivities are tricky to tease out – reactions can range from sleepiness to hyperactivity to skin rashes and tummy pain... anything, really, because food can influence every corner of our bodies.

But for some kids, food sensitivity is A Big Deal. It happens when their immune or nervous systems mount a hyper-response to certain foods.  Inflammatory chemicals are then released and they could be contributing to complex conditions such as asthma, ADHD, Autism, diabetes, celiac, and many more.

It is estimated that 1 in 3 children suffers from a food sensitivity (also called an intolerance), and this seems to be on the rise.

The message I want to bring you here is that food sensitivity is a symptom, not a diagnosis….

Food sensitivity is a call to look deeper into the resilience of the body.

I had this interaction with a mom recently....

A mom of three approached me, interested in running a food sensitivity test for her son who was experiencing ADHD-like behaviour, dry patchy eczema-like skin, and interrupted sleep.

This blood test runs about $300 and tests for an IgG immune response to over 200 foods. This mom thought it would help her identify the root cause of her son’s troubles.

Now, the validity of this test is hotly debated. IgG antibodies are "memory" antibodies; they can be triggered simply because they have seen a food for a second time. But an IgG test can be a helpful screening tool to see if any foods are eliciting an extreme response. If there's an extreme IgG response, that would be a red flag. Again, not a diagnosis, but a red flag indicating a potential source of irritation. We can use that information to then construct a careful elimination-provocation diet to determine if these foods are, in fact, contributing to symptoms. 

For this mom, though, I told her that I did not think the IgG test was the right place to spend her money…. for now.

This mom had observed that when her son ate cheese and tomatoes he got lethargic and irritable. Those were trigger foods for him that were likely to come up positive should we run the test. But the problem was not actually the cheese and tomatoes – the problem was the body’s inability to tolerate them because of reduced resilience.  So that is where I suggested she focus her energy first, before testing.

I gave this mom a copy of my book, which outlines the 2-pronged approach and Core Dietary Strategies for boosting resilience, and suggested she work on those strategies first. At the same time she was to keep out the cheese and tomatoes, any other food that was clearly causing noticeable symptoms.

At that point, after really working on raising resilience by following the strategies in the book, if her son was still not tolerating cheese and tomatoes (or anything else) she was to come back and we could consider the test as a way to go deeper and find other foods that could be burdening her son’s body and causing interference. 

But there was work for her to do first. Until the basics were covered, until resilience was stronger, I didn’t think it was worth shelling out the $300.

So here’s the take-home message about food sensitivities and IgG tests…

Food sensitivities are becoming more and more of a problem and there is no doubt in my mind that they are worth exploring if your child is exhibiting troubling symptoms - be they physical or mental/emotional.

If left undetected food sensitivities can cause myriad symptoms that involve the skin, the bowel, the brain, behaviour, hormones…. just about every body system. They can be contributing extra stress to your child's body that they just can't handle right now, and removing them be an important part of symptom resolution. 

IgG tests can highlight foods to which the IgG arm of the immune system could be over-reacting and can help us construct an elimination diet to see if they are actually problematic. But restricting a child's diet can be difficult and can open the door to nutritional deficiencies, so we have to be careful. The IgG test is not a diagnosis of an allergy; it is a screening tool to help identify irritation.

The real reason food sensitivity is becoming more and more common is that the physical resilience of our kids is deteriorating. Their digestive systems are less able to render foods hypoallergenic and their immune systems are more likely to respond inappropriately. The result? Food sensitivities.

Why is this happening? Here are a few possible reasons...

  • Increased accumulation to environmental toxins which puts an extra burden on our immune systems
  • nutritional deficiencies that undermine chemical processes in the body
  • reduced diversity of gut bacteria due to antibiotics, sugar, stress and increased exposure to chemicals and pesticides
  • genetically modified food interfering with digestive and immune response,
  • increased rate of cesarean births,

So it’s not that surprising that we are seeing a rise in the rate of sensitivities. But identifying and removing the foods as identified by a food sensitivity test is only a very small part of the solution. The real key to managing food sensitivities is to improve the health of the body.

If you do use the IgG food sensitivity test, use it as a guide to construct an elimination diet, don't consider it a diagnosis of food allergy. And I suggest you consider it only after you have done everything you can do to bolster your child's resilience.

Ready For More?....

Click to this video post to learn more about the gut-allergy connection.

If you have a baby, keep in mind that sensitivities can be thwarted by paying close attention to gut bugs when starting solid foods. Click here for more info on that.

If your child is struggling with self regulation issues (ADHD, aggression, anxiety, autism) check out my group coaching program Jumpstart Program to improve their resilience.



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