Hi everyone, Dr. Junger here.
The Gut and the microbiome that lives within it is the Wild West of medical research. (“Microbiome” is a fancy name for all the microorganisms that share our body.)
Each week there are new articles that showcase how the gut, the organisms that live within it, our brain, and our behavior cannot be neatly separated.(1) They are all connected with each other, and the health of the gut sits at the center of them.
The more we learn how to support the gut, the more we can positively impact many areas of our health.
Last week, we started our journey through the gut system with the intestinal flora. These friendly bacteria aid our body in so many ways including digestion, creation of b-vitamins and detoxification.
Today, we are going to focus on the second part of the gut system, the intestinal wall. This wall is our internal border to the outside world, and, as you will see, it plays a huge role in our health.
Let’s start with what the intestinal wall does, then go into how it’s damaged and what we can do about it.
The Digestive Tube: Your Body’s Busiest Border
Only three major organs come into physical contact with the outside world: your skin, your lungs, and your digestive tube. That’s why in the image above, the area on one side of the intestinal wall says the “outside” of the body.
It’s easy to see how the skin is the border between the inside and outside of your body. Healthy skin is uninterrupted; most things bounce off it. But the other two borders, the lungs and your digestive tube are more complicated.
Let’s start with the lungs.
When you breathe, air enters your body. Even though oxygen comes in, it’s outside of you until it passes into the lung’s pulmonary capillaries and is carried away by red blood cells.
The same is true for food and drink. When you swallow food, it disappears from your view and goes down the digestive tube. But it’s technically “outside” of you until it is broken down and absorbed through the intestinal wall.
Hence, the skin, the lungs, and the digestive tube encompass the three “borders” where the body draws a line between what is inside and what is outside. Of these three organs, your digestive tube is the largest and busiest.
The Intestinal Wall
The intestinal wall lines the digestive tube and is constantly in touch with foreign stuff, namely the food and drinks we consume and all the chemicals added to them. It’s also in touch with foreign organisms such as bacteria, yeast, parasites, and viruses, among others.
And unlike the skin, which is designed to keep most things outside and let very few things pass through it, the intestinal wall is designed to absorb everything that is useful to your body.
In order to absorb more nutrients, human evolution did something amazing. Our digestive tube adapted to make sure the cells of the intestinal walls would come in contact with food.
Because food was often scarce, this gave the body a better chance of absorbing whatever nutrients it could find.
The body achieved this incredible task by creating folds and sub-folds of the intestinal wall called villi and microvilli, which increased its contact surface area to—believe it or not—two hundred times the area of the skin covering your body.
Brick by brick
The cells of the intestinal wall look very much like a brick wall. Each cell is closely attached to other cells by tight junctions. But these are highly intelligent bricks. They keep what is foreign to the body (undigested food and microorganisms) out while simultaneously letting in whatever the body needs—digested food.
For this reason, intestinal wall cells must always remain intact and their tight junctions must remain tight. A missing cell or a loosened junction would allow undigested food, and the good and bad bacteria inside the digestive tube, directly into your body.
When we are missing intestinal wall cells or there is a loosening of the tight junctions—actual holes in the wall—this leads to a condition called hyperpermeability, or leaky gut. This is the beginning of many illnesses. An impaired gut barrier has been associated with numerous health conditions including skin issues, heart failure, depression, digestive impairment and autoimmune conditions.
Getting Rid of the Gunk
The intestinal wall cells are not just for absorption of nutrients. They are also in charge of exporting metabolic and other toxic waste outside the body into the digestive tube for elimination. Here this “gunk” joins along with whatever food the body didn’t absorb.
Most people think of their feces as whatever the body didn’t want or need to absorb from the food they ate. But this is only half the story. The cells of the intestinal wall are capable of capturing other waste, such as mucus, fat, and toxins from our blood, and dumping it into the tube for elimination. This is the exact reverse of absorption. Even if you eat nothing, your body can form feces with this waste.
I first noticed this during my first cleanse at We Care Spa. I ate nothing for ten days but I still produced stools. The average person usually passes remnants of food within two days, even if the system is backed up. Well into my detox, my body was starting to dig deep into my tissues for waste and dumping it into my digestive tube, where colonics then scraped it off like a dishwasher scrubbing at a dirty pot.
How the intestinal wall is damaged
Here are some of the major items that damage the intestinal wall:
- Lack of nutrients
- Opportunistic organisms (parasites, yeast, fungus)
- Toxins (chemicals, pesticides)
You will notice that many of the items on this list also damage the intestinal flora, the topic of last week’s newsletter.
We touched on many of them (stress, toxins, opportunistic organisms), so this week I’m going to focus on lack of nutrients and gluten.
Remember, the gut works as a holistic system, so protecting one part of the gut, say the intestinal flora or the intestinal wall, will help out the other parts as well.
This is why a good Gut Cleanse works best when it addresses most of the items on the list above.
Lack of Nutrients
Cells of the intestinal wall need certain building blocks or nutrients in order to keep dividing and forming new cells to replace expired ones. When this is not the case, cells fail to form and cover the gaps.
So what are some of these building blocks?
I’ll share with you two of the most important: L-glutamine and butyrate.
L-glutamine is an amino acid that is the primary nutrient for the cells of the intestinal lining. Here it helps to regulate cellular production and can help prevent and repair leaky gut.
L-glutamine is most concentrated in grass-fed beef, bison, chicken, and free range-eggs. Dairy products such as milk, yogurt, and cottage cheese are also high in it. Vegetable sources include red cabbage and parsley.
In addition to glutamine, there is another nutrient that is very important in supporting the growth of the intestinal wall. This nutrient is a short-chain fatty acid called butyrate.
The highest concentration of butyrate is found in our gut because it is created by our intestinal bacteria. Our bacteria produce butyrate from indigestible fiber like cellulose and pectin found in fruits, vegetables, sweet potatoes, grains, beans, nuts, and butter.
Butyrate has been shown in certain studies to be one of the major players in maintenance of the intestinal wall.(2)
It’s also been shown to reduce inflammation, regulate the immune system, improve metabolism, and increase stress resistance. This is a powerful combination of benefits.
Now that we’ve talked about some of the nutrients needed to support the intestinal wall, lets focus on a food that’s been shown to damage it, gluten.
I’ve spoken about gluten in this newsletter before and how it can cause problems for our health even if you are not celiac or have an autoimmune condition.
Remember when I talked about how the cells of the intestinal wall are held together by “tight junctions” that can open and close to allow nutrients to be absorbed.
This opening and closing of the intestinal wall is caused by a molecule called zonulin. We need zonulin but we don’t want too much of it, becauses our intestinal wall will open too wide or too often. This allows bacteria, pathogens, and undigested food to pass the wall and trigger the immune system.
Gluten causes increased amounts of zonulin to be produced, directly creating the conditions for leaky gut. (3)
At first, researchers thought that this occurred only in people with autoimmune conditions or celiac. But newer research has concluded that gluten triggers zonulin release in people regardless of autoimmunity.(4)
What does this mean for us?
This means that gluten affects the intestinal wall in all persons to different extents.
This is why the Clean Gut Cleanse as well as the Clean Cleanse removes gluten from the diet. Even if you do not remove gluten forever, you can benefit your health and your intestinal wall by removing it for a period of time.
Three Ways to Support the Intestinal Wall
1. Include L-glutamine and butyrate in your diet. The highest sources of l-glutamine are found in grass-fed beef, bison, chicken, free range-eggs, and dairy products. (Make sure to test dairy products to make sure they work for you.) Vegetable sources include red cabbage, raw spinach, parsley, and oats.
To encourage butyrate production, eat fiber-rich whole plant foods such as sweet potatoes, vegetables, fruit, nuts and properly prepared grains and beans. The highest natural source of butyrate is found in butter (3-4%) which may work for you if you are not on the cleanse.
You can also supplement with our Integrity powder for a boost of L-glutamine and our betaglucan, whose fiber helps increase butyrate production. These two supplement powders are especially useful if you are experiencing gut or digestive issues.
2. Reduce your intake of gluten. Gluten is one of the foods that causes the most trouble for my patients. It may not be necessary for you to remove gluten completely, but the research I’ve cited above shows that when we remove gluten for a period of time, it reduces one of the major causes of leaky gut. Try replacing your gluten-containing foods with fruit, rice, sweet potatoes, and some occasional gluten-free bread products.
3. Do the Clean Gut Cleanse. The Clean Gut Cleanse is set up to address many of the causes of gut issues today from diet and toxins to opportunistic organisms. This 21-day program helps to support the gut repair process and revive your health. I recommend doing a gut supportive program 1-2 times a year.
As we get deeper into our understanding of the gut, I hope you are enjoying how complex and remarkable our gut is.
Next week, I’ll show you how the immune system is intimately connected to the health of our gut. Have a great week.
To your health,
1. Mult Scler. 2014 Jul 28. pii: 1352458514541579. [Epub ahead of print]
Digesting the emerging role for the gut microbiome in central nervous system demyelination. Joscelyn J1, Kasper LH2.
2. The Journal of Nutrition, Biochemical, Molecular, and Genetic Mechanisms Butyrate Enhances the Intestinal Barrier by Facilitating Tight Junction Assembly via Activation of AMP-Activated Protein Kinase in Caco-2 Cell Monolayers1,2 Luying Peng,3,5 Zhong-Rong Li,4 Robert S. Green,3 Ian R. Holzman,3 and Jing Lin3*
3. Physiol Rev 91: 151–175, 2011; doi:10.1152/physrev.00003.2008. Zonulin and Its Regulation of Intestinal Barrier Function: The Biological Door to Inflammation, Autoimmunity, and Cancer, ALESSIO FASANO4.
4. Scandanavian Journal of Gastroenterol. 2006 Apr;41(4):408-19.Gliadin, zonulin and gut permeability: Effects on celiac and non-celiac intestinal mucosa and intestinal cell lines. http://www.ncbi.nlm.nih.gov/pubmed/16635908t