The Gut/Brain Connection – A Two Way Street

There are numerous examples of how the Gut and the Brain connect with one another both physically and comparatively.   We’re all familiar with the feeling of butterflies in the stomach

Butterflies in the stomach close up

before a stressful event, which is an example of emotions manifesting symptoms in the gastrointestinal tract (GIT).

 

There is also a physical connection whereby the vagus nerve serves as a pathway for information transmitted from the brain to the gut and back again. 

 

 

The following is a sampling of evidence-based material that helps to demonstrate how this connection can impact brain function.

1.  The enteric nervous system is sometimes referred to as the ‘second brain’.  It is embedded in the tissue of the gastrointestinal tract, which is a continuous tube that measures over 30 feet from the mouth to the anus.  It has 100 million neurons more than there are along the spinal cord or peripheral nervous system.  It is believed that the GIT is equipped with this complex system so that it can manage the job of digestion and absorption without help from the brain.  Animal studies have shown that if the vagus nerve is severed the enteric nervous system continues to function on its own.  According to Emeran Mayer, Professor of Physiology, Psychiatry and Biobehavioural Sciences at the David Geffen School of Medicine at the University of California, “The system (enteric nervous system) is way too complicated to have evolved only to make sure things move out of your colon.”material that helps to demonstrate how this connection can impact brain function.

2.  Another similarity between the ‘2 Brains’ is that 95 percent of the body’s serotonin is found in the gut.  The neurotransmitter serotonin is involved in mood control, depression and aggression and therefore often only considered with issues relating to the brain.   In fact, irritable bowel syndrome has been attributed at least in part to too much serotonin.   This would also explain why some people find themselves with digestive upset when prescribed an SSRI (Serotonin Reuptake Inhibitor believed to increase the extracellular level of the neurotransmitter serotonin).

3.  Recently it was discovered that information transferred from the brain to the GIT only accounts for 10% of the overall activity, whereas 90% of the information transmitted is from the GIT to the Brain.

 

Consequently, a person’s stomach or intestinal distress can be the cause or the product, (but more likely the cause) of anxiety, stress, or depression.

4.  Thanks to the growing field of neurogastroenterology (the study of the brain, the gut and their interactions), the scientific link between gut flora and mental health is being established.  A study out of McMaster University in 2011 compared the behaviours of normal eight-week-old mice and mice whose guts were stripped of their microbiota,  (formerly known as the microflora).  The microbiota is located in the intestines, it contains  tens of trillions of microorganisms, over 1000 different species.  The mice that had their microbiota stripped revealed higher levels of cortisol and altered levels of brain chemicals that have been implicated in human anxiety and depression.  According to Jane Foster, the study’s lead author,

“Everybody knew that stress and anxiety could lead to gastrointestinal symptoms, but we looked from the bottom up and showed that the gut could communicate with the brain.  It was the first demonstration that the gut itself could influence brain development.”

 

5.  The GIT is thought of as the main point of entry for inflammation in the body; it is  the location of 60% of the body’s immune system and contains tens of trillions of microorganisms known as the microbiota (formerly known as the microflora).  It is believed that inflammatory and immune responses can travel through the vagus nerve from the abdomen to the brain.  This inflammatory response can influence how different neurochemicals (such as serotonin) are produced, it can impact energy production in the brain as well as the management of hormones such as cortisol, (a hormone which is released in response to stress).

Improving the balance of the microbiota can help reduce inflammation, support the immune system and aid in the digestion and absorption of nutrients, all of which can impact brain function.

Health professionals are beginning to acknowledge the gut/brain connection and are administering treatments accordingly. Dr. Kelly Brogan, MD states that,

“In the case of chronic illnesses like depression, it isn’t that you were born with bad genes or low serotonin.  It is far more likely that you are experiencing an unhealthy inflammatory balance stemming from a sick gut.” 

 

The key to managing inflammation in the body and healing the gut relies primarily on lifestyle modifications.  A basic protocol would include recommendations with respect to exercise, stress management, strategic supplementation and diet, for example:

  •     Exercise: Including gentle movement daily with cardio not exceeding 35-45 minutes one to three times per week
  •     Stress Management:  Daily breathing, meditation or mindfulness practice
  •     Strategic Nutrition:  Natural anti-inflammatory foods like ethically sourced fish, turmeric and fermented foods.  Supplementing with probiotics and fish oil. as well as probiotics, possibly more supplements, depending on the individual
  •     Avoiding pro-inflammatory foods such as too much red meat, sugar, alcohol, dairy and gluten.

 

The gut/brain connection is a two way street and the likelihood that the GIT has influence over brain function is good news.  Consequently, taking steps to build good bacteria in the lower intestines and reduce inflammation in the body can have a profound effect on overall health as well as mental health.

All information contained in this Blog is for information purposes only.
 Do not make any significant changes in lifestyle or nutrition without first consulting a qualified practitioner.

 

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Jan 21, 2014 | Posted by in Blogs, Uncategorized | Comments Off on The Gut/Brain Connection – A Two Way Street