(Part 3 of 4) "Gut Primer" Video Series: How does leaky gut lead to autoimmunity?Feb 23, 2021
Hello, hello, welcome to part 3 of this 4 part video series on the importance of fixing your gut in order to fix your immune system.
So in the previous parts we learned about how gut dysfunction was closely related in literature to immune conditions, and then we learned which two mechanisms in the gut lead to the inflammation that serves as a hallmark for these conditions. Now, we're going to really start to connect some dots and talk about a proposed mechanism for how the onset of autoimmunity occurs.
In this video we'll examine one of the most prominent research theories on the pathology of autoimmunity. It frames leaky gut - one of the inflammatory gut conditions that we discussed in Part 2 - as one of the preconditions necessary for what results in the immune system becoming confused and the autoimmune condition developing to begin with.
The proposed mechanism has 3 steps, which we'll go over briefly now then elucidate in a moment with an example.
First you eat something, and your body fails to properly break down the protein molecules. This happens more easily with large proteins like the ones found in gluten, dairy, and eggs - it's no coincidence these are the most common allergenic foods! It has to do with their large protein structure.
Next, these big intact proteins make their way to the intestines where their size damages the tight junctions and creates those freeways we discussed previously in the gut lining. The proteins sneak out into the bloodstream where they're tagged by the immune system as invaders, and are subject to an inflammatory response.
Now, some food proteins are molecularly very similar to those in our own tissue, so when this escape happens often enough, the immune cells eventually become confused and cross-react with our bodies, beginning to chronically attack one or more parts of us.
A common example of this involves the protein gluten - found in wheat and other grains - and the thyroid gland.
Thyroid autoimmunity is highly associated with gluten sensitivity and while gluten sensitivity is associated with many autoimmune conditions, for thyroid this is especially the case. In fact, for those with celiac disease, Hashimoto's disease is 4 times higher than in the general population.
So why is this? A proposed explanation is via what experts term "molecular mimicry".
When gluten is consumed in an individual with a leaky gut, the gluten particles "leak" out into the blood stream.
Once in the blood stream, it's large size means that it may cause an abrasion to the vascular system walls, or other tissue, and in doing so it attracts immune cell soldiers patrolling the body, who then tag it as foreign and try to destroy it.
The soldiers take a sort of picture of its molecular structure and send out a signal to the other actors in the immune system.
You can think of this signal sort of like a ‘wanted’ flyer with a sketch artist's interpretation of the criminal included on it.
This ‘wanted’ flyer eventually makes its way to the artillery component of the immune system, informing them to use their toxic chemical weaponry on any compound they run into that looks like this.
As the artillery patrols the body, it comes across the thyroid gland, and look! It appears to have a very similar chemical structure.
Except, the chemical structure belongs to the thyroid instead. This is because the molecular structure of gliadin, one of the proteins in gluten, is extremely similar to that of the thyroid proteins.
This results in an inflamed thyroid gland that can cause negative symptoms, or even permanent damage that prevents it from functioning properly without exogenous thyroid hormone supplementation.
Likewise, many who suffer from thyroid autoimmunity find that removing gluten from the diet can result in meaningful gains in their thyroid-related symptoms, likely because it interrupts this process.
To return to our ‘wanted’ sign metaphor - its sort of like the sketch artist who depicted the likeness of the criminal only depicted a very specific thing about the wanted-person... like that they had a mustache, and some glasses.
However, this affords the opportunity for confusion if there happen to be other people in the world with mustaches and glasses.
While we focused our example on food, this confusion can also occur with chemicals, microbes, or anything that is passing through our GI-tract donut holes that manage to somehow get past our gut structure and into our tissue.
Maybe you're wondering: “well, why does this happen?”
As we've covered, having an intact gut structure, as nature intended, will prevent this confusion from ever occurring.
After all, if our gut isn't leaky, then step 2 in this 3 step process won't ever occur, and so the cycle will be interrupted.
Therefore preventing a leaky gut is the best way to prevent autoimmunity. And as we saw previously, dysbiosis leads to leaky gut, so we've got to prevent that, too.
And that does it for Part 3.
So at this point, I'd like to encourage you to rewatch any of the videos that you may need to if you're feeling confused about any of the concepts so far. You'll need to grasp these concepts pretty well in order to get the most out of our final installment, part 4, where we'll talk about how so many people go wrong in trying to tackle this, and where you can effect some really meaningful change quickly.
Thanks for watching, and I'll see you in the next video!