Can you do your own food intolerance testing?5
Food intolerance can be the root cause of a number of symptoms such as skin problems (e.g. eczema, like I have), respiratory problems (e.g. asthma), migraines, gastrointestinal issues and more. I recently came across a post by Empowered Sustenance about How to Test Yourself for Food Sensitivities using the LNT (Neuro-Lingual Testing) Coca Pulse test. Coincidentally, it was just two days after I’d had blood drawn for IgG food intolerance testing. My first thought was: “Did I just spend several hundred dollars for this food intolerance testing when I could have tested myself?” I also wondered if I could use the pulse test as a way to test my son for foods I suspect he might be sensitive to.
Getting my IgG panel results back, I figured I had an opportunity to verify the LNT Coca Pulse test against my blood work results. Specifically, I wanted to know: Would the pulse test show that I was sensitive to the foods to which I produce a lot of IgG antibodies? Would the pulse test show the same degree of reactivity as the IgG results, that is – if I produce a lot of IgG antibodies to one food, will my heart rate increase more?
IgG testing for food sensitivity/intolerance
IgG antibodies are produced by the immune system as a long-term resistance response – the idea is that with food intolerance and sensitivity, the body produces more antibodies against foods that you can’t tolerate. (An IgG reaction differs from an IgE reaction in that IgE antibodies are produced in an ‘allergy’ response – difficulty breathing, hives, swelling, and possible anaphylactic shock).
The advantage to this type of testing is it’s easy (a simple blood test), and it can test for anywhere from 100 to 200+ foods from a single blood draw. The biggest drawback is that the testing is not cheap, and typically runs in the neighborhood of $300-$500 to test for 200+ foods, and depending on the laboratory, it can take a few weeks to get the results. (My testing was done through my naturopathic doctor, so there was an additional cost for that appointment. The blood work was done through Gamma Dynacare).
LNT Coca Pulse test
In contrast, the DIY food sensitivity test I explored is a modified version of the Coca pulse test – testing one food at a time. The basic principle is that if you are intolerant or allergic to a specific food, a stress reaction results which raises your heart rate. You can read the original book by Dr. Arthur F Coca (pdf).
The advantage to the pulse test is that the cost is minimal – just a stopwatch and some time to check your pulse rate, along with the foods you want to test.
I conducted the test 1.5 hours after my last meal and made sure I was relaxed and seated comfortably in a quiet room so that I could concentrate on counting my pulse with a stopwatch. To test: I simply placed a piece of food in my mouth for at least 30 seconds and then took my pulse for a full minute. (Full instructions on how to conduct the test yourself can be found here). After each food, I rinsed my mouth out with filtered water, and took another baseline heart rate measurement.
My LNT Coca Pulse test results
I tested five foods with which I have a high IgG reaction. (IgG levels higher than 30 U/ml is considered an ‘Elevated reaction’, and these are foods I usually avoid). I also tested three foods that I have a ‘normal’ IgG reaction (less than 24 U/ml). I also included filtered water as a control. The table below shows my results, in the order that I tested the various foods.
|Food tested||IgG concentration (U/ml)||Baseline heart rate (bpm)||Average baseline heart rate||Food reaction heart rate||Average food reaction heart rate||Difference in average heart rate|
|Initial reading||n/a||79, 79||79||n/a||n/a||n/a|
|Filtered water (control||n/a||78, 79||78.5||83, 77, 77||79||0.5|
|Cheese (marbled cheddar)||68*||77, 78, 77||77.3||82, 78, 80||80||2.7|
|Raw milk||50||78, 75, 77||76.7||86, 82, 85||84.3||7.6|
|Raisins||39||74, 77, 77||76||79, 81, 78||79.3||3.3|
|Egg white||65||76, 73, 70||73||77, 75, 73||75||2|
|Egg yolk||42||71, 69, 70||70||75, 72, 71||72.7||2.7|
|Apple||0||76, 73, 74, 72||73.7||72, 72, 70||71.3||-2.4|
|Coconut oil||11**||74, 73, 78, 75||75||75, 77, 77||76,3||1.3|
|Organic cane sugar||16||73, 71, 71||71.7||77, 74, 75||75.3||3.6|
(*IgG score is for casein – a major component of cheese, **IgG score was for coconut)
A positive test result with the LNT Coca pulse test is an increase in heart rate by at least six points. Based on my results, the only food I tested as having intolerance to is milk, as it is the only food that elevated my heart rate. Despite having a higher IgG antibody count sto egg white and casein, neither eggs nor cheese raised my heart rate significantly.
Should you bother testing yourself for food intolerances?
There are a number of drawbacks in conducting this test – the biggest being the variation in baseline heart rate, which in turn affects the accuracy of a 6-point ‘positive’ reaction. Your heart rate can vary due to time of day, being startled by a minor interruption like the phone ringing, or your body position. It’s also time-consuming to manually measure and record your heart rate. Of course, using a heart-rate monitor during the course of day would help normalize the baseline variation and reduce the human error and time involved.
Prior to having any food sensitivity testing done, I had suspected that I was sensitive to dairy and nuts. (I didn’t test nuts because we didn’t have any on hand). The LNT Coca pulse test was at least able to confirm my suspicions about my milk intolerance. So while the test isn’t very sensitive, it may be a good first step. Keep in mind though, that it could lull you into a false sense of security – all other foods I tested to which I have high IgG antibodies didn’t cause a 6 beat per minute increase.
If you suspect you have a food sensitivity, but you don’t want to shell out for the expensive IgG testing, your best bet may be to keep a food diary and follow an elimination diet. Record the foods you eat, along with the symptoms you experience. Then, eliminate a food you suspect and see if your symptoms change. While you may not be able to pinpoint minor intolerances, you should be able to identify major ones.
Is it worth getting IgG food intolerance testing done?
Ultimately, food sensitivity testing is to help you determine which foods you want to avoid so that you can lessen your inflammation symptoms. There are some who don’t believe that IgG testing is reliable or that it’s just plain quackery. However, the proof is in the pudding – if you find that you eliminate certain foods and find improvement in your health, then testing does have a true value.
The biggest benefit to getting IgG testing done is that it’s a way to find many triggers right away without having to take the weeks or months required to test individual foods through an elimination diet. It could also help you find foods that are less common triggers, or are more obscure. For example, despite avoiding grains since going “paleo”, I did occasionally eat white rice, which is not usually a trigger for food sensitivities, yet it turns out to be one for me, at an IgG level of 35 U/ml. Being Chinese and having eaten rice for most of my life, I never would have suspected rice as the cause for some of my troubles.
It has been about 6 weeks since I originally got my IgG results – and that’s how long it’s been since I’ve had any dairy, eggs or raisins. In that time, my eczema had cleared up, but interestingly, two days after I conducted this pulse test, my neck had a pretty severe eczema flare-up.
The bottom line is that for me, it was worth having paid for food sensitivity testing, as it was the push I needed to eliminate eggs (a common food intolerance), and to find out there were 26 other foods I reacted to – the IgG testing has been a good template for me to do an elimination diet. If I’d used the LNT Coca Pulse Test as a guide, I would not have eliminated anything but milk (which I’d all but eliminated before), and as a result, my symptoms would probably have persisted. I tried the LNT Coca Pulse Test on my son to see if he was sensitive to dairy, and the test was inconclusive at best, since his baseline heart rate was a bit erratic, and it’s tough to get a 6 year old to have the patience to sit quietly without protest to adequately do the test. Ultimately for him, I think we’ll have to do an elimination diet and take out dairy to see if it improves his symptoms.