Hi! Welcome back to the Pelvic Empowerment IBS Series
My name is Tori and I am doctor of physical therapy who specializes in pelvic dysfunction,
which means I treat things that can go wrong around the pelvis including bowel
dysfunction. This means I run into humans with IBS in the clinic often.
In May, I decided to try my best to unpack what I have learned about IBS in a video series,
and today I want to add a third installment building on my previous video on IBS trigger
foods—this time focusing on the more specific question that I proposed—what
foods are you as an individual human specifically sensitive or intolerant to?
We will first define the difference between food sensitivities or intolerances and actual
food allergies, then we will explore the different tests that exist to determine
food sensitivities and intolerances, and we’ll spend a little extra time really deep
diving into home food sensitivity test kits before ending the video.
If you haven’t yet, please do watch the first and second video installments in this series,
as I do plan on building on topics explained in those videos,
in this video! You kind find links to those videos, as well as timestamps
and links to all the studies mentioned in this video in the description below!
Alright, let’s dive in!
It’s important that we first define the difference between a food sensitivity or
intolerance and an actual food allergy. As the American Academy of Allergy, Asthma, and
Immunology explains: “A food intolerance response takes place in the digestive system. It occurs
when you are unable to properly breakdown the food. This could be due to enzyme deficiencies,
sensitivity to food additives or reactions to naturally occurring chemicals in foods. Often,
people can eat small amounts of the food without causing problems.”
Whereas: “A food allergic reaction involves the immune system. Your immune system controls how
your body defends itself. For instance, if you have an allergy to cow’s milk,
your immune system identifies cow’s milk as an invader or allergen. Your immune
system overreacts by producing antibodies called Immunoglobulin E (or IgE). These
antibodies travel to cells that release chemicals, causing an allergic reaction.”
Let’s unpack that a little bit more.
The reason I bring up the difference is because, if you are truly sensitive or intolerant to a
food, you should be able to eat a small amount of it without issue. Whereas, if you are truly
allergic to a food, even a small amount of that food would cause an allergic reaction.
The tricky thing with IBS is that sometimes a very small amount of
food can cause an “attack,” so is that an allergic reaction… or is
that sensitivity/intolerance… or is that something different all together?
While true allergic reactions can occur in the digestive system and cause stomach cramping,
which could mask as an IBS-like symptom,
most of the time allergic reactions involve vomiting, hives, itchiness, shortness of breath,
trouble swallowing, dizziness, swelling, a rash of sorts—symptoms that clearly indicate something
other than IBS is at play. The great news is, if you are at all suspecting a true food allergy,
you can follow up with an allergist and get those immunoglobulin E antibodies we
mentioned earlier measured and find out if you actually have an allergy—or an immune
system response—to said food. The test will either be positive or negative—so you’ll get
a super clear and straightforward answer, which I feel like is a rarity in the world of IBS.
On the other hand, food sensitivities or intolerances, as we learned, take
place in the digestive system… so symptoms typically present as nausea, stomach pain,
gas, cramps, bloating, diarrhea, and then maybe even heartburn, vomiting, or headache. But the
first few symptoms we named could absolutely be masked as IBS symptoms. Stomach pain, gas,
cramps, bloating, and diarrhea can go hand in hand with IBS, which makes the question
“is this a food intolerance or is this my IBS?” a little more challenging to answer.
So, how do you test for individual food sensitivities or intolerances?
One option for food intolerance testing that I think has a lot of
value is hydrogen breath testing, and I would recommend that anyone
with a diagnosis of IBS undergo this testing. Here’s why and how it works.
This 2014 article does a great job explaining the mechanism of hydrogen breath testing:
“Bacteria in the bowel generally produce hydrogen gas on fermentation of carbohydrates.
Let’s pause here and emphasize carbohydrates. That means hydrogen breath testing can be used
to test for sugar-based intolerances, but can’t be used to test for something like
a gluten intolerance, because gluten is a protein, not a sugar. Back to the article!
In the bowel, bacteria can only do this when dietary carbohydrates are not absorbed in the
small intestine and stay as undigested material as they travel along the digestive tract into the
large intestine. Though some of the hydrogen gas produced by the bacteria is expelled as flatulence
or in making other molecules such as sulphides, acetate and short chain fatty acids but most of
the gas is absorbed across the lining of the large intestine into blood stream. The gas is
then transported to lungs via the blood stream, and from blood it is exchanged into the airways
of the lungs and breathed out, or exhaled. The only source of hydrogen gas in the breath can be
from bacterial fermentation in the bowel. The same applies to the gas called methane which is exhaled
by some people but not all. The bacteria in the large bowel make methane from the hydrogen. The
amount of hydrogen and methane gases breathed out from the lungs can be easily measured by
taking a breath sample, and measuring the gas concentrations via a breath-testing machine.”
In other words, if you are digesting your carbohydrates well, there should be little to no
hydrogen and potentially methane in your breath. If you aren’t digesting your carbohydrates well,
then there will be abnormally high amounts of hydrogen and potentially methane in your breath.
So then, if you aren’t digesting dietary sugars normally (aka you have carbohydrate
malabsorption), we can test for it! The most common example that comes to mind
is of course lactose intolerance, lactose being the sugar in milk.
But this breath test can also be used to evaluate sucrose, fructose, and sorbitol.
Furthermore, this breath testing can be used to diagnose Small Intestinal Bacterial Overgrowth,
or SIBO, and it can tell you how quickly or slowly food is moving through the small intestine.
So I say, if you are working with an IBS diagnosis but have not undergone
a hydrogen breath test, why not take one and determine with clarity: whether or not SIBO
is at play in your condition at all, are you intolerant to certain sugars yes or no—again,
this test will give you a clear outcome, a rarity in the world of IBS—and how well is
food moving through your small intestine? All of this information is valuable,
in that you can use it to further tailor your diet to your specific, individual needs.
The other test that is getting a lot of love right now is the at home food
sensitivity testing kit. If you think you have a food sensitivity or intolerance because you
used an at home food sensitivity test kit, I would gently encourage you to
reconsider. IBS already demands a lot of attention to diet, and the last thing you
need is to further restrict foods that you aren’t actually sensitive or intolerant to.
Let’s explain why these tests are not scientifically supported.
We mentioned earlier that a true allergy causes the body to produce antibodies
called Immunoglobulin E, or IgE. According to this 2018 article published in the Journal of Allergy
and Clinical Immunology, “Just as quantitative enzyme immunoassays can be used to measure IgE
antibodies to foods, these same assays can be used to measure IgG antibodies or IgG4
antibodies to foods. These tests are performed in many reputable laboratories, and there is no
reason to doubt their validity and reliability, that is, the tests are in fact accurately and
reproducibly measuring IgG antibodies directed against food proteins. However,
the measurement of IgG to foods is promoted to diagnose “food sensitivities” that might manifest,
according to websites promoting the testing, as—a laundry list of things INCLUDING IBS!
Here is the catch…
“However, the production of IgG antibodies to foods is a normal immunologic phenomenon. IgG
antibodies to foods are found in virtually all healthy individuals. In fact, contrary to the
notion that the development of IgG or IgG4 antibodies could lead to food intolerance,
the development of such antibodies has specifically been linked to the
development of food desensitization or tolerance.”
So then, these food sensitivity tests are valid and reliable, in that they
do accurately measure IgG antibodies; however, IgG levels have nothing to do with sensitivity
or intolerance. They actually seem to be a marker of desensitization or tolerance.
So, if you took one of these tests, you’d essentially see what you’ve been
eating recently, with higher IgG markers for the foods that you eat more often. And then,
if the results are misinterpreted,
you could be encouraged to stop eating foods that you are actually quite tolerant of!
By definition, a food intolerance is difficulty digesting a certain food and having some sort of
unpleasant physical reaction during that period of difficult digestion. While someone could
absolutely have both IBS and a food intolerance in tandem, recall that digestion does NOT take
place within minutes of eating. Digestion takes hours, and so symptoms related to a true food
intolerance would come on HOURS after eating the food. IBS attacks that occur within 15-20
minutes of eating are therefore very unlikely related to a true food intolerance—rather,
in my opinion, IBS attacks further support the idea of brain-gut dysfunction and an
over- or under-active gastrocolic reflex, as I outlined in the first video in this series.
Pairing this knowledge with the knowledge that you’d have to eat
a reasonable amount of that food to have a intolerant reaction—or, in other words,
that small amounts of a food aren’t significant enough to elicit a true intolerant reaction—it
seems to me that the best way to uncover food sensitivities that cannot be tested with hydrogen
breath testing would be via a well kept food journal and a very good registered dietician.
I propose that, if you are truly suspecting a food sensitivity or intolerance other than lactose,
sucrose, fructose, or sorbitol, the best thing you can do is keep a very detailed food and symptom
journal for at least 2-3 weeks—writing down very specifically everything you eat, when you eat it,
and when/what symptoms you experience. Then, bring this journal to a registered dietitian—ideally one
who specializes in IBS or GI disorders—who can help you determine actual potential food
sensitivities and intolerances, which can be further sussed out via an elimination diet.
To really bring home my point on food sensitivity testing, let me highlight a 2004 study that
investigated IgG-based food elimination diets in humans with IBS. This study looked at a
total of 150 humans with IBS, and randomized them into two groups to partake in a 3 month
diet—one group partook in a “true” diet, a diet that actually excluded the foods with
higher IgG antibody test results—and the other group, the control, partook in a “sham” diet—a
diet that excluded the same number of foods, but not the food that yielded higher IgG antibodies.
Now, the results of this study would have you believe that
IgG testing as a form of food sensitivity testing is worthwhile for those with IBS,
as 10% of those on the “true” diet felt a reduction in their symptoms,
and those that were very compliant saw a 26% reduction in their symptoms.
However, the “true” diet eliminated, in very high percentages, milk, eggs,
and wheat. Whereas, the sham diet eliminated these foods in much lower percentages.
This 2005 article says it best, “The recent paper by Atkinson and colleagues regarding
IgG food antibodies and irritable bowel syndrome (IBS) fails to compare like with like. Regardless
of the IgG results, the treatment group excluded significantly different foods
to the control group, particularly those foods which appear to exacerbate symptoms of IBS.”
I think this leads nicely into the next topic that I will be discussing in this
series—IBS and lactose / gluten intolerances specifically, as foods containing lactose
and gluten do seem to, generally speaking, exacerbate IBS symptoms.
Alright, thank you so, so much for watching—I am really enjoying creating this IBS series!
As I mentioned, I am planning next to cover lactose & gluten intolerances specifically
and their relationship to IBS, as well as FODMAPS, and the overlap between IBS and SIBO!
I also plan to cover: soluble vs insoluble fiber,
specific dietary considerations for symptom management, stress/anxiety/and mood and their
effects on IBS, Linzess and Trulance, sleep, and potentially more holistic IBS treatments…
but if you have a different IBS-related topic you want me to add to the series, please let
me know in the comments below! I do try really hard to read and respond to all of my comments.
I am genuinely so excited and honored to be doing these request videos,
so thank you so much for watching, commenting, and requesting!
Please, if you found this video helpful, give it a thumbs up, share it, and, finally, subscribe
to my channel for more content surrounding pelvic health (and sometimes life things, too!)
Don’t forget to check meowt on instagram, and thank you so much again for watching.
Have a wonderful rest of your day, and I’ll see you in the next video, bye!