The digestive process begins at first sight or smell of food. The sight and smell of food actually translates into a neural signal that tells your brain to tell your stomach to start releasing digestive enzymes.
When you eat a bite of food, it gets broken down in your mouth by chewing. Amylase, which is an enzyme in your saliva starts digesting the food. The partially digested food goes down your esophagus to your stomach where it gets mixed and churned with digestive juices that contain hydrochloric acid (HCl) and mucus before making it’s way to the small intestine.
One of the main jobs of the small intestine is to help you absorb nutrients. The wall of the small intestine is about 20 – 25 feet long in adults. It is folded up very tightly for maximum surface area so you can absorb as much nutrients from the food as possible. If you were to lay out the surface of the small intestine you would find that the lining is about as big as a tennis court.
On the top barrier of the lining of the small intestine you will find villa lined with single cells called epithelial cells. In between the epithelial cells are what’s called tight junctions. Tight junctions act as lockable doorways into your body. They allow small broken down single nutrients (amino acids, fatty acids, simple sugar) to pass through and keep out anything that shouldn’t come into your body like undigested food, microbes, and toxins.
What happens when we eat gluten containing food?
Gluten is a group of proteins that get broken down into smaller proteins. If you are eating wheat gluten it gets deamidated or broken down into gliadin and glutenin by an enzyme in your gut calledtissue transgultaminase (tTG). The presence of tTG signals receptors called zonulin on the tight junctions to break open so tTG can present the broken down proteins to the gut-associated lymphoid tissue (GALT) which is the part of the immune system that lays just underneath the surface area of the gut.
Why do the broken down parts of gluten get sent to the immune system?
Because the immune system has the ability to destroy potentially harmful substances like antigens and to make antibodies so that when you eat gluten in future, there will be an army of immune cells waiting there to attack. Problem is, if you have celiac then your immune system doesn’t just attack the broken down gluten, it attacks tTG as well.
This is very bad because tTG is you and is being made by your body. When your immune system starts attacking your own body this is known as autoimmunity. To make matters worse, tTG is not just present in your small intestine, but it is present all over your body including in your skin, your brain, your pancreas, joint tissue, muscle, your thyroid, your liver, and throughout your nervous system. This is why if you have any autoimmune disease you have to consider gluten as one of the triggers and need to avoid it.
If you eat gluten on a daily basis this means that your tight junctions are constantly open allowing not just the gluten but other large molecules like bacteria, microbes, toxins, undigested food like polysaccharides to leak into the bloodstream. This is what’s known as gut permeability or leaky gut. This also means that your immune system is always active which eventually leads to chronic inflammation.
Chronic inflammation destroys the lining of the gut making it nearly impossible to absorb nutrients.
Who Becomes Gluten Intolerant?
In order to become gluten intolerant there has to be a few factors present. One is that you have a genetic predisposition. Those that have a genetic predisposition carry one of the genes that code for overactive zonulin (DQ2, DQ8). 2. A person has to have gluten in their diet. If you simply avoid gluten, this response can not happen. 3. There has to be a way for the antigen to get into the body. Zonulin breaks open tight junctions and allows deamidated gluten and other antigens to leak into the body.
If you have been told you have an autoimmune disease of any kind such as rheumatoid arthritis, hashimotos, lupus, etc then you are gluten intolerant and should avoid gluten if you want to live without symptoms. Gluten can continue to stimulate your immune system for up to 6 months after last ingestion.
- Wheat Belly by William Davis MD
- Lose the Gluten, Lose Your Gut, Ditch the Grains, Save Your Brain by Thomas Chaney MD