One of the biggest mistakes people make with gut health protocols is expecting success from a one-size-fits-all solution. Ten different people can have leaky gut or other gastrointestinal (GI) symptoms for 10 different reasons.
It’s important to understand why your gut isn’t working before you try and fix it. The most effective clinical approach — and one that I use with all of my patients — is to follow what we call the “north-to-south” approach.
Our digestive system depends on multiple parts working in sequence. If any step along this top-to-bottom hierarchy doesn’t work properly, it will trigger breakdowns in function elsewhere along the GI tract and the entire system will work less efficiently.
In the north-to-south model we evaluate each digestive step in sequence, identify breakdowns along the way, and address them before moving downward to the next step.
For example, if you want to heal the microbiome — located in the large intestine at the south end of the hierarchy — but you have a problem further north with gallbladder function or stomach acid production, you will have limited success repairing the microbiome.
Below is the digestive hierarchy from north to south. In upcoming articles I will break down these parts into more detail and offer steps to identify where breakdowns are occurring and how to address them.
Diet is the first stop on the north-to-south hierarchy. If fast food, pastries, and boxed pizza are staples in your diet, nothing you do to support your digestion is going to have much effect.
The most common inflammatory foods are:
- Artificial sweeteners
- Processed foods
- Foods fried in processed oils
In best-case scenarios, simply cleaning up the diet and adding in some temporary digestive support may be all that’s needed to restore gut health.
A variety of diets exist depending on your primary gut issue, such as gluten-free, FODMAPs, and AIP. The diet you need depends on the underlying causes of your gut health problems, something I address in my new gut health course.
The minute we start to chew, the brain initiates multiple nervous system functions along the digestive pathway. This enables us to produce saliva, swallow, increase blood flow to the gut, release digestive enzymes, activate gut motility, and more.
The brain must function well in order to support good digestive function. This is why it’s common to see gut issues in people with brain injuries, brain degenerative diseases, dysautonomia, or brain development disorders.
Without addressing these issues, you will have limited success addressing gut issues further south in the GI tract.
Chewing. It is essential to pre-digest your food as much as possible with thorough chewing. This takes strain off the stomach, pancreas, and intestines, and reduces your chances of gut inflammation and food intolerances.
First, count how many times you chew to establish your chewing habits. Then get in the habit of chewing until your food is liquid. Doing so will greatly aid the rest of your digestion.
Saliva. The moment you start chewing, your brainstem activates saliva production. For proper digestion you need adequate amounts of saliva. It not only starts to break down your food but also it activates key cranial nerves involved with swallowing, vagus nerve function, digestive system blood flow, enzyme production, and gastrointestinal motility.
Saliva also contains immunoglobulins that help prepare the immune system for exposure to food proteins, and it produces digestive enzymes to help to break down starch.
If you are always the last to finish eating or you must drink lots of water to finish a meal, observe whether you have a lack of saliva — especially if it has become worse over time. This can be a sign the feedback loop between the brain and the GI tract is not working well.
However, these low saliva conditions don’t necessarily involve brain pathways:
- Sjogren’s syndrome, an autoimmune disease which creates antibodies against saliva glands.
- Uncontrolled diabetes.
- Various medications that reduce saliva production, especially hypertensive medications.
No matter the cause, reduced saliva production cuts down on this important initial step of the north-to-south hierarchy and must be addressed before moving further south.
Swallowing. Swallowing initiates peristalsis, the contraction of muscles of our esophagus and intestines that moves food from north to south.
The inability to swallow pills, capsules, or food can be a red flag that the brain-gut connection via the vagus nerve pathway is not working properly. For more information on the vagus nerve see my brain book and my Save Your Brain online course.
Important: If you have swallowing issues in combination with constipation, slow intestinal motility, and food in the stool, this could indicate dysfunction in the upper brainstem. Early neurodegenerative disease and early Parkinson’s should be ruled out with the help of a qualified healthcare practitioner.
If you have trouble swallowing, you must address it before moving further south on the pathway.
The stomach and hydrochloric acid
As food enters the stomach, it distends and releases hydrochloric acid (HCl), which plays a number of key roles in the north-to-south pathway.
HCl is extremely important for digesting food, particularly protein and meats. Sufficient stomach acidity is also necessary to trigger the valve to the small intestine to open and to activate the release of additional digestive secretions.
Sufficient stomach HCl helps:
- Prevent the development of leaky gut by breaking down food proteins into smaller amino acids. Otherwise, undigested foods are recognized as dangerous invaders by the gut’s immune system, which can lead to systemic inflammation.
- Sterilize the small intestine to help prevent the overgrowth of bacteria.
- Prevent food poisoning and parasites from gaining a foothold in your digestive tract.
- Stimulate the gallbladder to secrete bile to break down fats.
- Stimulate the pancreas to secrete digestive enzymes.
The small intestine
When food enters the small intestine, this triggers a number of important digestive functions.
Pancreatic enzymes. Once food passes from the stomach into the small intestine, the pancreas secretes digestive enzymes to help digest sugars, fats, proteins, and starches. This busy, multi-purpose organ secretes about 8 ounces of juices a day into the small intestine.
Sufficient pancreatic enzyme output is extremely important in preventing food intolerances. The more thoroughly the gut digests foods, the less likely your immune system is to react to them.
Gallbladder. The gallbladder contracts and releases bile to emulsify fats so they are more easily digested and absorbed. This prevents damage to the lining of the small intestine and also helps you absorb fat-soluble vitamins such as vitamins A, D, E, and K.
Gallbladder function and bile are also necessary for:
- Microbiome health
- Managing gut inflammation
- Regulating fat and sugar metabolism
- Regulating metabolism of drugs and supplements
- Biotransformation of toxins (liver detox)
- Preventing leaky gut
It is impossible to repair a leaky gut, restore gut function, or improve the gut microbiome in a significant way as long as gallbladder sludge and stones are an issue.
Micronutrient absorption. The small intestine is lined with tiny protrusions called microvilli. Because their job is to absorb nutrients, they must be healthy.
Tight junctions. Tight junctions are the connections between the cells of the intestinal wall that open and close as necessary to allow micronutrients into the bloodstream but keep invaders out. They must function properly to prevent leaky gut — when undigested food proteins, toxins, and pathogens such as viruses and bacteria cross into the bloodstream, this leads to systemic inflammation and other symptoms.
Remember, in a north-to-south hierarchy if you have trouble with any of these small intestine factors, you must address them before moving further south on the pathway.
The large intestine
The last stop before elimination is the large intestine, or colon, whose job it is to absorb water and electrolytes.
Your large intestine is also home to the microbiome, which powerfully influences all aspects of our health by releasing peptides, hormones, and necessary bacterial byproducts that impact our brain, cardiovascular, and immune function.
The large intestine is where probiotics and prebiotics have their effect. In addition, the more diverse your diet and the more plant fibers you consume, the more diverse gut bacteria you will have, which supports a healthier microbiome and immune system.
Address your north-to-south pathway
Now that you understand the concept of north-to-south, you understand why one-size-fits-all digestive protocols fail many people.
You can’t start treating the gut at the microbiome level; you have to start north and move south:
- Proper diet
- Brain function
- Adequate saliva production
- Chewing your food well
- The ability to swallow and initiate gut motility
- Sufficient hydrochloric acid, digestive enzymes, and bile
- Intact microvilli and intestinal walls to enable micronutrient absorption and support a healthy immune system
- A vibrant microbiome
- Absorption of water and electrolytes in the colon
By evaluating and addressing the digestive system from north to south, you are more likely to succeed at repairing leaky gut, the gut microbiome, and our overall gut health and immune function.
This may seem overwhelming, especially if you have multiple symptoms and can’t access a functional medicine practitioner. In my new gut health course, Gut Health: Solving the Puzzle — A top-to-bottom solution strategy, I address each of these steps in depth, teach you how to recognize symptoms of dysfunction at every stage, and show you how to make the necessary changes to recover gut function.