The small intestine is a sophisticated barrier between "self" and "non-self".
Lunch Hour Lesson #37
By now you may have heard of the term “leaky gut” as the common name of a condition called intestinal hyperpermeability. Today I want to talk about what that is, what are the most likely causes, and what the effects are in the body.
Before we talk about leaky gut in particular, let’s talk about the small intestine. Your small intestine is a tube located directly south of the stomach in the digestive cascade, and its lining is only one cell thick.
It is very thin for a reason, because the primary function of the small intestine is to absorb nutrients from the food you eat and pass them through and into the blood stream. In that way, you can say it is a barrier between “self” and “non-self”.
But, it is supposed to be very selectively permeable. Only the very smallest molecules of broken down food, namely glucose, fatty acids, and amino acids, are supposed to be allowed to pass through the lining and into the blood stream.
Normally, the cells of the intestinal lining open up a tiny bit to let these small molecules through, and then close back up tightly.
In the condition of leaky gut, however, the small intestine becomes hyper permeable, meaning that the cells open wider than they’re supposed to, and let bigger molecules of food pass through.
The fact that they’re bigger means that these molecules haven’t been digested down as fully, so whole proteins or fats may escape into the bloodstream.
When the immune system cells that are circulating in the blood stream, surveying that everything is in order, see these bigger particles of food, they go on high alert, sensing a foreign invader. This is because they’re only supposed to “see” the small glucose, fatty acids, and amino acids coming through.
So, in short, intestinal hyperpermeability, or leaky gut, causes an elevated immune response to whatever particles leak through.
What are some of the causes of the small intestine becoming hyper permeable? Basically anything that causes the lining to become irritated and inflamed:
- processed foods
- sugar
- lack of good-quality sleep
- over-exercising
- environmental toxins and pesticides like glyphosate (RoundUp)
- emotional stress and grief
Basically, anything that stresses the body also stresses the small intestine and over time can cause it to malfunction.
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Now to talk about the effects. Many people wonder about why instances of food allergies and autoimmune disease are on the rise. One strong theory is that it has to do with leaky gut.
Here’s how that would work. I just mentioned that in a leaky gut situation, the lining allows larger molecules to escape through into the bloodstream than it should. The immune system sees this large molecule and mounts an immune response to it, because it sees it as non-self. It shouldn’t be there.
If the person keeps eating a particular food under a leaky gut situation, the immune system will constantly be attacking that undigested particle of food that leaked through, leading to food allergies and sensitivities. If you eat that food, you now feel unwell, because the immune system is reacting to it.
There are other issues as well. Certain proteins in foods are very similar looking, molecularly, to proteins in our own body tissues. This is called “molecular mimicry”.
For example, the molecular structure of gliadin, the protein component of gluten, looks very much like the molecular structure of the thyroid gland. When gliadin (a big molecule) escapes through the intestinal lining because of leaky gut and enters the bloodstream, the immune system marks it for destruction.
Unfortunately, this means that the immune system also causes the body to attack its own thyroid tissue. That’s what autoimmunity is – when the immune system attacks its own tissues. I’ve noticed that many of my clients who have autoimmune thyroid disease see their symptoms improve when they remove gluten from their diet.
The good news is that there are protocols that I use in my practice to identify the presence of leaky gut in clients and help them to heal and seal their intestinal lining. It usually involves removing certain foods that they’re sensitive to and undergoing a therapeutic program of repair.
It is very important, however, to also manage stress, eat a non-inflammatory diet, and sleep well to make sure that the thin lining doesn’t become hyper permeable again.
Our bodies are in a constant state of breakdown and repair – we don’t just “get healthy” and then go about our merry way forever. We have to actively maintain health because new stressors always arise. That’s life!
Weekend Tip
Keep a food journal today. Do you have any digestive or mood reactions after a certain meal? Start looking for patterns as the days go by between what you eat and how you feel.
Lunch Hour Lessons with Allison
Watch this week’s Facebook LIVE – Lunch Hour Lesson #37: Food Allergies and Autoimmune Disease: Could It Be Leaky Gut? Each week I bring you a topic related to nutrition and health that I think is interesting, and give you a lesson to take with you into your daily life. Watch Live on Facebook, Wednesdays, 12:30pm PST!
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