Many people may have experienced “stress causing stomach pain” or “excitement causing an upset stomach” even though the problem did not originate directly from the digestive system.
Currently, the medical and health science fields are increasingly interested in the relationship between the “gut” and the “brain,” leading to the concept called Gut-Brain Axis, or the communication axis between the gut and the brain.
For this reason, the gut has been dubbed “the second brain of the body” (Second Brain) because it not only functions to digest food but also plays an important role in mood, immunity, sleep, and overall quality of life.
What does it mean that the gut is the second brain?
The gut is called the “second brain” because it has its own nervous system and is home to trillions of microorganisms, or the Gut Microbiome, which can communicate with the brain through nerves, hormones, and the immune system.
Many studies have found that gut health may be related to mood, stress, sleep, immunity, and various chronic diseases. Therefore, caring for the Gut Microbiome is another important factor in holistic health care.
What is the Gut Microbiome?
Inside the human gut, there are more than 100 trillion microorganisms, including bacteria, fungi, and various microbes. These groups of microorganisms are collectively called the Gut Microbiome. The important functions of the Gut Microbiome include:
- Helping digest food and absorb nutrients
- Producing certain vitamins, such as vitamin K and some B vitamins
- Enhancing the immune system
- Preventing the growth of pathogens
- Producing important substances related to brain and nervous system function
When the microorganisms in the gut are balanced, the body usually functions efficiently. However, if the balance is disturbed, it can affect health in many ways.
Why is the gut called the “second brain”?
Within the gut wall, there is a specific nervous system called the Enteric Nervous System (ENS).
This system consists of more than 100 million nerve cells that control gut movement, digestion, and secretion of various substances. Additionally, the gut can communicate with the brain through:
- Vagus nerve
- Immune system
- Hormones
- Neurotransmitters
This creates a two-way communication network between the brain and the gut, known as the Gut-Brain Axis.
How is the gut related to emotions?
Many people may not know that over 90% of serotonin, a neurotransmitter related to mood, happiness, and sleep, is produced in the digestive system.
Although serotonin from the gut does not travel directly to the brain, the Gut Microbiome can affect the production of neurotransmitters and nervous system function.
Several studies have found a connection between an imbalance of gut microorganisms and:
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- Chronic stress
- Anxiety disorders
- Depression
- Sleep problems
- Chronic fatigue
Is it true that over 70% of immunity is in the gut?
The gut is one of the important organs of the immune system because it is the first line of contact with food, pathogens, and foreign substances from outside. A balanced Gut Microbiome can help:
- Stimulate immune function
- Reduce inflammation in the body
- Maintain the strength of the gut lining
- Reduce the chance of pathogens entering the bloodstream
Conversely, if the gut microorganisms are imbalanced, it may be associated with chronic inflammation and many non-communicable chronic diseases.
Signs that may indicate gut health imbalance
Although symptoms are not specific, common signs include:
Digestive system
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- Frequent bloating
- Chronic constipation
- Alternating diarrhea and constipation
- Intermittent abdominal pain
- Indigestion
Overall health
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- Easy fatigue
- Reduced immunity
- Poor sleep quality
- Easy stress
- Decreased concentration
- Feeling unrefreshed despite adequate rest
Behaviors that unknowingly harm the Gut Microbiome
- Eating too much processed food, such as fast food, very sweet foods, and high-sugar drinks
- Insufficient sleep; regularly staying up late may affect the diversity of gut microorganisms
- Accumulated stress; chronic stress affects communication between the brain and gut
- Unnecessary use of antibiotics, which may reduce good gut microorganisms
- Lack of exercise; regular physical activity helps promote the diversity of gut microorganisms
How to care for the Gut Microbiome in daily life?
1. Increase natural fiber Fiber is an important food for good gut microorganisms, including
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- Colorful vegetables
- Fruits
- Whole grains
- Various nuts
2. Eat foods containing probiotics such as
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- Yogurt
- Kefir
- Kimchi
- Miso
- Some fermented foods
3. Get enough sleep Aim for consistent 7-9 hours per night
4. Manage stress such as
-
- Exercise
- Breathing exercises
- Meditation
- Adequate rest
5. Exercise regularly At least 150 minutes per week, according to general health recommendations
New trend in health care starts from the gut
Currently, the concept of preventive medicine and holistic health places more importance on Gut Health because the gut not only affects digestion but is also linked to:
- Immune system
- Mental health
- Sleep
- Weight control
- Chronic inflammation
- Long-term quality of life
Therefore, caring for the gut has become one of the key approaches to building good health from within.
FAQ Frequently Asked Questions about the Gut and Gut Microbiome
Q: Is the gut really the second brain?
A: It is a scientific metaphor because the gut has its own nervous system and can communicate with the brain through the Gut-Brain Axis.
Q: Does the Gut Microbiome really affect emotions?
A: Research has found that gut microorganisms are related to the production of neurotransmitters and nervous system function, which may affect mood and stress.
Q: Does frequent bloating mean an imbalance of gut microorganisms?
A: It may be one of the causes, but there are other factors such as diet, irritable bowel syndrome, or other digestive diseases. A medical evaluation is recommended if symptoms are chronic.
Q: Is it necessary for everyone to take probiotics?
A: Not necessary for everyone. Gut health care should start with a balanced diet and sufficient fiber. The use of probiotics should be considered based on individual suitability.
Q: What are the benefits of Gut Microbiome testing?
A: Assessing the composition of gut microorganisms may help understand gut health and plan preventive health care better, under the guidance of medical professionals.
Take good care of your health, starting with gut balance
The gut may have more functions than many people think because it is not only related to digestion but also connected to immunity, mood, sleep, and overall health through the Gut-Brain Axis network.
If you have chronic bloating, abnormal bowel movements, frequent abdominal pain, or are interested in preventive health care on a deeper level, assessing digestive system health and gut microorganism balance may be a starting point to better understand your body.
Center of Excellence for Gastrointestinal and Liver Endoscopy, Phyathai 2 Hospital is ready to provide consultation, diagnosis, and holistic digestive health care by a team of specialized doctors and standard medical technology to help plan appropriate continuous and comprehensive health care for each individual.
Dr. Chote Luangchosiri
Director of the Center of Excellence for Gastrointestinal and Liver Endoscopy
Phyathai 2 Hospital
