The Gut-Brain Connection
Understanding disorders of gut-brain interaction: The gut-brain connection
Written by Dr. Fiona Callender, ND
The process of being diagnosed with Irritable Bowel Syndrome, “IBS”, can be one that is filled with frustration. It may include many tests, scopes, and doctors appointments… only to be told there’s nothing physically wrong. You might turn to google or TikTok and start eliminating foods that might be triggering you. But what if it’s not the food?
Although eliminating foods can sometimes reduce symptoms short-term, the underlying cause of IBS is not often food related. Most of the research in this area is really shifting towards understanding of IBS as part of a collection of gut-related conditions called Disorders of Gut-Brain Interaction (DGBI).
Understanding disorders of gut-brain interaction
Disorders of gut-brain interaction are a group of disorders that involve a miscommunication between the gut and the brain. There are actually dozens of conditions characterized by chronic gastrointestinal symptoms arising from interactions between the gastrointestinal tract and the brain. As we learn about this collection of conditions, it’s important to remember that the brain is playing a role here, but it’s certainly not all in your head.
To begin to understand disorders of gut-brain interaction and how to treat them, we need to think about digestive concerns as existing on a continuum with “altered physiology” at one end, and “altered perception” at the other.
On one end, we have physical conditions, that have notable altered physiology. These include; inflammatory bowel disease (IBD), pancreatitis, infection, and celiac disease. In these conditions there are physical changes or damage to the tissues in the bowel. We can see or measure the changes and disease progression.
On the other end of the spectrum, we might have conditions such as IBS, chronic bloating, functional heartburn, functional constipation. These are conditions where we see no physical damage, but our perception of pain and/or discomfort is a very real experience. In some cases we have overlap and patients may experience more than one condition at once. For example, some patients with Inflammatory Bowel Disease - where inflammation is the culprit leading to symptoms and damage in the gastrointestinal tact - may also have symptoms of IBS - a condition with no physical damage, but the miscommunication between the gut and the brain produces many very real symptoms.
This mis-wiring may lead to physical changes including:
Motility changes (how fast or slow food moves through the system)
Visceral hypersensitivity (how intensely we feel the movement, gas, changes in our organs)
Changes in the tissues and immune system in our gut
Central Nervous System (CNS) changes
Almost half of women may meet the criteria for atleast one condition under the disorder of gut-brain interaction umbrella. We are totally missing the mark if we treat everyone the same, cut out some foods, and ignore the nervous system effect on your symptoms.
Understanding sensitization:
Sensitization is a heightened response to a stimulus that is otherwise non-threatening - and wouldn’t cause symptoms in most people. Our nervous system is essentially sending alarm signals when it shouldn’t. We sense movement and digestion (that wouldn’t normally be felt) and then, to make matters worse, we turn up the pain. Gas is a normal phenomenon in the digestive tract - we all produce gas through the process of digestion. Those with IBS often have a heightened nervous system response and perception to this same gas. When we look at studies that actually measure the gas, about 75% of people with bloating have no abnormal gas production.
Now, you might be thinking, “But I can SEE my bloating… I look 6 months pregnant!”. That’s not necessarily more gas production either.
In normal digestion, our diaphragm rises slightly to allow space for a bigger meal. Our abdominal wall muscles adapt and contract to manage pressure in the abdomen. When our digestive system is under stress, or signals get misinterpreted, our diaphragm inappropriately drops instead of rising. This shifts our abdominal contents forward - making it appear like a balloon in some cases!
So, how do we fix this?
The solution to these symptoms has to take into account the bi-directional connection between the gut and the brain. We can remove some of the stimulus by removing foods that cause more gas… but if we aren’t addressing the sensitivity, we can’t manage this long term. We need to down-regulate those signals and shift how the brain perceives that information.
Some of the most evidence-based, and newly emerging treatments for IBS include mindfulness, breathing exercises, cognitive behavioural therapy and gut-directed hypnosis. For functional constipation there is even a place for pelvic floor therapy. These are all treatments that may help rewire the communication between the gut and the brain and down-regulate signals of “high alert”
But what about the low-FODMAP diet?
If you’ve ever spent time googling ways to cure your IBS, you have likely heard of the low-FODMAP diet. FODMAPS are a collection of fermentable carbohydrates that do tend to produce more gas than some other foods. There is research on using a low-FODMAP diet to reduce symptoms of IBS, but we really only want to use this as a “test”, not as a treatment. This can sometimes help people get out of a hypersensitive state but we only recommend this for two weeks or less! The goal is always to bring the FODMAPS back. FODMAPS include some really healthy foods that are filled with fibre and nutrients. It’s really important that we don’t increase restriction of create fears around foods. Research has actually shown that restriction tends to lead to more symptoms over time.
Ultimately, a treatment plan will depend on your history with your symptoms and what triggered them, and although we will address what you are eating, we will also focus on how you are eating. We will take a look at what your lifestyle and routines look like, how you cope with stress, how you are sleeping, and how you are managing any other conditions or symptoms. The symptoms you are experiencing are real, not just in your head, but if we ignore the nervous system miscommunication, we are missing the biggest piece of the puzzle.
Curious to learn more about how we can support you with your gut health? Book a complimentary meet and greet with one of our naturopathic doctors.