When we last left off in our Fixing Digestion series, our food was slowly moving from our stomach, through the pyloric sphincter, and into the twisty turny world of our intestines.
Pretty accurate view of a small intestine
But before we dive in, it’s important to note a what occurs at this sphinctorial junction.
As discussed in Pt. 2, the acid content of our food passing through the pyloric sphincter triggers a chemical message to our pancreas and gallbladder, instructing them to release their juices. Pancreatic juices contain an abundance of digestive enzymes critical for future digestion, while the gallbladder contains bile salts which emulsify fats so that we can absorb them. If our stomach acid is low, or either of these organs is struggs, downstream digestion will suffer.
Cool. Moving on.
The Small Intestine
The small intestine is where the molecular chunks and tangles of food particles are broken down into single molecules. These move to the intestinal walls, through the intestinal walls, and then into the bloodstream or lymph. Consider: until this point, the food is still technically outside the body, moving through a long, walled-off tube. The small intestine is where the outside meets the in. Nourishment ensues.
Enzymes are the key to this process. Many come from our pancreatic juices, as mentioned above, while others are secreted by the cellular lining of our small intestine. These little chemical creatures chop apart the bonds in our food molecules, turning chains into pieces. Starch becomes individual glucose molecules; protein become individual amino acids, and fatty acids are emulsified (shoutout to bile!) and cleaved from glycerol heads.
Enzymes and peristalsis waves assist these nutrients to the walls of our small intestine, where bajillions of tiny, wavy hair-like structures called villi entrap these molecules. New enzymes shuttle them through the delicate, single-celled walls from one side of the digestive tract to the other. Once on the other side, these nutrients move into the bloodstream or lymph. They can then be used for energy by the muscles, built into tissues, stored for later use, or used as catalysts for other body functions.
Enzymes at work. Looks like these ones came from Amazon.
While our enzymes work to salvage all the beneficial nutrients, waves of peristalsis keep foodstuffs moving downstream. Anything indigestible -like fiber- or foods that take too long for our digestive tract to tackle -like partially chewed plant matter- continue on to the large intestine. Personal metabolism, fiber content, hydration status, gut inflammation, stress and hormones all influence the speed at which this process takes place.
why does it have to be so hard
The small intestine is a busy and efficient place. Its complex system evolved over millenia so that we could extract the maximum nutrition from our omniverous diet with the least amount of digestive risk. It worked great- when our food came straight from Mother Nature and processing was limited to fire. Unfortunately, this delicate system turned out to be woefully unprepared for the insults of our modern-day food supply.
Today, the fragile walls of our small intestine come into regular contact with toxins like glyphosate, mutated proteins from GMOs or puffed grains, and anti-nutrients from poorly prepared grains and legumes. The delicate villi are damaged, becoming smooshed and flattened like a patch of dead grass. When this happens, we lose the ability to fully digest food in this area, as the surface cells on these villi contain many of the enzymes needed for the final separation of double molecules into single molecules.
Worse, damage to our small intestinal wall ruins its integrity as a barrier. As the cells weaken, the microscopic junctions between them loosen, allowing partially digested food particles to pass through. While it may seem harmless to have partially digested nutrients cruise into the bloodstream, it’s not. Food fragments, especially proteins, are incredibly triggering to our immune system, inciting inflammation and other reactions. This is because our body’s ability to break down food is limited to the inside of the digestive tract and cannot take place within the bloodstream, or muscles, or lymph. When food enters these zones without complete digestion, it’s useless at best and harmful at worst. This state of increased intestinal permeability usually goes by its street name, Leaky Gut.
Leaky gut is a bummer. We suffer pain during digestion, deal with chronic headaches and fatigue, and watch in despair as our faces break out in acne. Gas, diarrhea, and constipation are everyday adventures. Our immune system goes into overdrive and we drag our run-down selves from one exhausting job to the next. In those susceptible to autoimmune disease, flares are triggered.
Magnified view of an extremely leaky gut
Fixer upper
The first step in improving small intestine health is to remove potential irritants. With the cells of our digestive tract regenerating every 7-ish days, the good news is that our body has an incredible ability to quickly heal.
The first action item is removing additives and artificial ingredients. This includes food dyes, artificial sweeteners, sugar alcohols, stabilizers (any “gum” ingredient), and preservatives. The popular advice to avoid food with ingredients you can’t pronounce is a good one to put into play here.
The next stop is removing whole foods that contain high levels of gut irritants. Grains, legumes, nuts and seeds are the primary offenders here. Because these foods are all technically “seeds,” their goal is to resist digestion as they pass through our body. To this end, they contain a variety of digestive disruptors -like lectins and enzyme inhibitors- that can cause inflammation along our gut lining. While these compounds can be significantly reduced by traditional preparations like soaking, sprouting, and fermenting, removing them entirely for a short period of time will contribute towards the fastest healing.
Next up: inflammatory proteins. While I always like to make the point that gluten and casein are only conditionally inflammatory -it depends on the individual consuming them, the sourcing, and how they’re prepared- it’s wise to remove these during a gut healing regimen. This is because these partially digested proteins seem to be especially inflammatory if they sneak through a leaky gut wall and into the bloodstream. So unless you plan to churn out the homemade sourdough and find a local source of raw A2 milk or goat milk, hold off on wheat and dairy.
Lastly, reduce consumption of sugars in all forms, including starches. When the gut lining is damaged, we lose our ability to fully break down and absorb the various sources of sugar in our diet. Instead, these head to the large intestine where they can fuel an overgrowth of pathogenic bacteria. Worse, these bacteria may begin to head north, following the food source into our now compromised small intestine. This condition, called small intestinal bacterial overgrowth (SIBO) can cause dramatic leaky gut and inflammation on its own.
healing, with a little help from my friends
What can you eat? Clean proteins, healthy fats, and cooked vegetables are the best foods for healing the gut lining. Our cells need the protein to regenerate, fats to nourish and heal, and vegetables for their micronutrients. Bone broth, meat stock, slow cooked meats and well-steamed vegetables are your leaky gut’s best friend.
Eat this
Avoid raw foods or anything rich in fiber, as these can irritate an already inflamed gut. With compromised small intestine function, you’re unlikely to fully digest these foods anyway.
Supplementation with l-glutamine is helpful in healing the small intestine. This amino acid provides an energy source specific to the cells lining our small intestinal walls.
It’s also wise to do a round of enzyme supplements at this point. While the goal is to boost your body’s own ability to produce these, remember that this is a fragile time. Adding a little extra enzymatic help will increase your digestion and absorption of important nutrients from your food.
take heart
Leaky gut is an incredibly common condition; it’s probably a safe bet to say that we’re all somewhere on the spectrum at any given point in time. The way I see it, it’s more a matter of damage control than perfect cellular health. Luckily, we’re resilient creatures. If you suspect leaky gut in your own intestinal world, try a gut healing protocol for a few weeks and see if you feel any better. It can’t hurt, and it’s delicious.