MICROBIOME
The Second Brain You Didn’t Know You Had: Your Gut!
It Also Affects Your Mental Health.
“There’s no such thing as good and bad bacteria or fungi. It’s not good and bad. It’s just whether there’s too much of it or too little of it and things are out of balance, so the ‘bad things’ have an opportunity to prosper.” — Nigel Palmer
Have you ever experienced butterflies in your stomach before an important event? That’s the enteric nervous system at work!
The enteric nervous system (ENS) is often called our body’s second brain. This is because it is always in contact with the one in our head.
What Is the Enteric Nervous System?
The ENS comprises a network of neurons that line our gastrointestinal tract. This system is responsible for digesting food, absorbing nutrients, and eliminating waste. It is also responsible for maintaining the health of our gut microbiota.
The enteric nervous system is directly linked to the brain via the vagus nerve. This connection allows the two systems to communicate with each other. For example, when stressed, the brain sends signals to the enteric nervous system that can lead to changes in gut motility and secretion of digestive juices.
The ENS is also thought to play a role in mood and emotions. This is because it contains several neurotransmitters also found in the brain. For example, serotonin is a neurotransmitter that regulates mood and anxiety. It is thought that healthy gut microbiota is necessary to produce serotonin properly.
The enteric nervous system is a network of neurons that line the gastrointestinal tract from the esophagus to the rectum.
The ENS comprises two layers of neurons: The myenteric plexus is located between the inner and outer layers of the digestive tract wall. The submucosal plexus is found in the submucosa, a layer of connective tissue beneath the mucosa (the lining of the digestive tract).
The enteric nervous system has three main functions:
- Controlling digestion
- Regulating blood flow and mucus secretion in the gastrointestinal tract
- Responding to changes in the environment, such as pH or temperature
Research has shown that the enteric nervous system can influence our behavior and cognition. The ENS is a complex system that is only beginning to be understood. It is vital to our overall health and well-being.
How Does the ENS work?
There are two types of communication between the central and enteric nervous systems: afferent and efferent.
- Afferent communication occurs when information flows from the intestines to the brain. This communication handles relaying messages about gut sensations like hunger, fullness, and pain.
- Efferent communication happens when information flows from the brain to the intestines. This type of communication handles regulating things like digestion and blood flow.
But how does all this communication happen?
When we eat something, it arrives in our stomachs in pieces. As these pieces travel down into the small intestine, they’re broken down further by gastric acid and enzymes. These tiny particles stimulate receptors in our gut lining, sending electrical signals through afferent nerves to the brain.
The brain then processes these signals and sends electrical signals back down through efferent nerves to the gut, telling it what to do next.
For example, if you’ve eaten a big meal, your brain will tell your stomach to stop producing acid and start digesting food.
The enteric nervous system constantly sends information to the brain via the vagus nerve, the longest cranial nerve in the body. This nerve starts in the brainstem and extends down to the abdomen.
The vagus nerve carries information about our environment, such as temperature, taste, and smell changes, from the digestive tract to the brain. This allows the brain to respond accordingly and adjust our physiological processes (for example, increasing or decreasing stomach acid production).
The ENS also can operate independently from the central nervous system. This is because it contains more than 100 million nerve cells — more than what’s found in either the spinal cord or the peripheral nervous system.
Scientists sometimes refer to it as a “second brain.” And while it may not be able to think abstract thoughts as our minds can. This second brain can make complex decisions and control many involuntary functions like digestion, heart rate, and blood pressure.
The enteric nervous system is essential for our health. It keeps our digestive system running smoothly and helps us respond to our environment and decide what we need to do to survive.
So next time you sit down to a meal, remember that you have two brains working hard to take care of you!
What is the Microbiome, and Why is it Important?
The microbiome is a community of microorganisms that live on and in the human body. It is a complex system with more than 100 trillion microorganisms. These microbes help the digestive system process food, protect against pathogens, and maintain a natural barrier against inflammation.
The gut microbiome is a complex ecosystem of bacteria, viruses, fungi, and other microorganisms that inhabit the intestinal tract. This is the largest organ in the human body and significantly impacts your health.
The gut microbiome has many vital functions, including regulating immune function and hormone levels. It also helps to digest food and extract nutrients from it.
A healthy gut microbiome is essential for good health. An imbalance in the gut microbiome can lead to several health problems, including obesity, diabetes, and inflammatory bowel disease.
Maintaining a healthy gut microbiome requires a balance of different types of bacteria.
Firmicutes help to break down complex carbohydrates and digest dietary fiber — Bacteroidetes help to break down proteins and absorb vitamins and minerals.
A healthy gut microbiome also depends on a variety of other factors, such as a nutritious diet, adequate sleep, and reduced stress levels. Eating a diet high in processed foods, for example, can disrupt the gut microbiome and lead to an imbalance of bacteria.
Ensuring you get enough sleep and reducing stress levels are also crucial for gut health. Sleep helps regulate the immune system, and stress can negatively impact the gut microbiome.
How Your Gut Affects Your Mood and Anxiety Levels
We now know that the gut and brain are connected, which means that anxiety can affect your gut health. The role of bacteria in the gut is essential for mood and anxiety. As a result, people with generalized anxiety disorder tend to have higher levels of certain bacteria in their guts than those without this condition.
The gut-brain connection is a two-way street. Not only can anxiety affect your gut health, but your gut health can also affect your anxiety levels. This is because the gut produces many of the same neurotransmitters found in the brain, including serotonin and dopamine.
A healthy gut is essential for good mental health. Probiotics may also be helpful for some people in managing anxiety and mood disorders. (Check with your doctor before taking probiotics, as they can interact with some medications.)
So next time you have butterflies in your stomach before giving a big presentation or get motion sickness while reading on a bumpy bus ride, remember that it’s not all in your head — quite literally!
The enteric nervous system constantly sends messages to your brain (and vice versa) about what’s going on in your gut. And while we may not yet fully understand all the complexities of this relationship, one thing is for sure: mind and body are more interconnected than we ever could have imagined.
What do you think about the connection between the gut and the brain? Let us know in the comments!
Sources:
Please share it with your friends and family if you enjoyed reading it.
You may also sign up to receive updates when I publish new material!
If you’re new to Medium and want to show your support, consider becoming a member through my page to gain unrestricted access to my current articles and thousands of other authors!
Your membership fee directly contributes to my work since I receive a share of your monthly payment at no additional expense to you.
Instagram | Twitter | YouTube | Support me/Follow me on other platforms
© Alejandro Betancourt, 2022. All Rights Reserved.
