A Closer Look at the Gut-Brain Axis and Why it Matters for Overall Health

Posted August 20, 2025 by Monarch Medical

 

Did You Know Your Brain and Gut Are Connected?

 

There is a communication system in your body that links your brain and your digestive system. This is called the gut – brain axis. It’s a two-way communication pathway that allows your gut and brain to send signals to each other. This connection plays a major role in digestion, mood, immune function, and overall health.

Let’s take a closer look at how it works.

 

There are Two Components of the Gut-Brain Axis

 

1.Enteric Nervous System: Your Gut’s Own Nervous System

 

The enteric nervous system is a large network of nerves located in the walls of your esophagus, stomach, intestines and colon.  It’s sometimes called the “second brain” because it can operate independently of the brain and spinal cord.

It has two main parts:

  •  Myenteric plexus -Controls the movement of muscles in your gut, helping food move through your digestive system.

  • Submucosal Plexus– Regulates blood flow, helps release digestive enzymes, and manages absorption of nutrients.

Together, these plexuses help:

  • Move food through the digestive tract (motility)

  • Control how your body breaks down food

  • Monitor your gut environment

  • Communicate with the immune system and gut bacteria (microbiome)

2. Central Nervous System: The Brain and Spinal Cord

 

The central nervous system includes the brain and spinal cord. It controls higher-level functions like:

  • Thinking and memory

  • Emotions

  • Movement

  • Stress response

  • Hormone regulation

The brain is constantly sending and receiving messages from the gut. These messages influence everything from digestion to how we feel emotionally.

 

The Vagus Nerve: The Main Highway

 

The vagus nerve is the largest and most important nerve connecting the brain and gut. It runs from the brainstem down to the abdomen, passing through major organs like the heart, lungs, and digestive tract.

The vagus nerve:

  • Sends information from the gut to the brain

  • Helps control digestion, heart rate, and breathing

  • Plays a role in calming the body after stress

When the vagus nerve is working well, it helps keep your body balanced. But if it’s not functioning properly, it can lead to digestive problems and mood changes and other symptoms.

 

How Do the Gut and Brain Communicate?

The enteric and central nervous systems are in constant communication. Signals travel back and forth to help your body respond to what’s happening in the digestive system and elsewhere.

This communication affects:

  • Metabolism (your body turns food into energy)

  • Digestion
  • Immune system  responses
  • Hormone levels

When something goes wrong in one system, it can cause problems in the other. For example, chronic stress can lead to stomach pain, while gut inflammation may contribute to anxiety or depression.

 

The Gut Microbiome: Your Gut’s Community of Good Bacteria

Your gut microbiome is made up of trillions of bacteria, viruses, and other microorganisms that live in your digestive tract. Most of these bacteria are beneficial and support your health in many ways.

They help with:

  • Breaking down food

  • Producing vitamins

  • Regulating the immune system

  • Preventing harmful bacteria from taking over

Importantly, gut bacteria also influence your mental health.  They produce neurotransmitters – chemical messengers that affect how you feel.

One of the most well-known neurotransmitters is serotonin, a chemical that helps stabilize mood, reduce anxiety, and improve sleep.

According to Oshi Health (2025), around 90% of the body’s serotonin is made in the gut, and then sent to the brain. This helps explain why people with digestive disorders like IBS (Irritable Bowel Syndrome) often also experience symptoms like anxiety or depression.

 

The Takeaway

Your gut and brain are deeply connected, and problems in one area can affect the other. A healthy gut can improve not just digestion, but also your mood, immune health, skin, and more. If you’re experiencing symptoms like frequent stomach pain, bloating, fatigue, chronic inflammation or mood changes, it may be time to take a closer look at your personal gut brain axis. With our holistic approach at Monarch Medical, we understand the connection between physical and emotional health. If you’re struggling with symptoms, come talk to us about ways to support your gut and brain for improvement in your overall health.

 

 

Reference

Myers, A. (2024). Gut health and anxiety: The surprising connection. Oshihealh.com