Authors:
Md. Harold Ignacio Colino, Liaison Psychiatrist
Dr. Carlos Arturo Rojas, Gastroenterologist
Dr. Nohra Liliana Zuluaga, Second-year Resident in Psychiatry
Dr. Lorena Cerón, Second-year Resident in Psychiatry
Dr. Laura Soto Figueroa, Third-year Resident in Psychiatry
Many people attribute it simply to stress or "a bad day," but few wonder if their daily habits, such as what they eat, how much they move, or how they sleep, may be influencing their emotional well-being more than they realize. (1,2)
For a long time, it was thought that the intestine served only to digest food. (1,3) However, science has shown that this organ plays a much broader role in the body's overall well-being. (2,4) Inside it lives a complex ecosystem of microorganisms that participate in digestive and immunological processes, and even in the regulation of mood. (1,2,3)
Today it is known that gut health is deeply connected to physical and mental health. (1,5) Maintaining a proper balance in the gut microbiota can influence daily energy levels, stress response, and how the body manages inflammation. (6) That is why more and more health professionals are talking about the gut as a key ally for overall well-being. (7,8)
The gut is not just a digestive tube; it is a complex biological factory where substances that regulate stress and help emotional stability are produced. (8.9)
But what exactly is the gut microbiota and why is it called "the invisible organ"?
The microbiota is the collection of trillions of microorganisms (bacteria, viruses, fungi, and archaea) that inhabit the digestive tract. It is called an “invisible organ” or “virtual organ” because, although it is not a human tissue itself, it weighs between 1 and 2 kilograms and performs vital functions that the body cannot, for example: (9, 10)
- Probiotics participate in the production of essential vitamins (such as B vitamins and vitamin K). (10)
- It strengthens the immune system against pathogens. (10)
- It extracts energy from food that humans cannot digest on their own (10)
- They participate in processes that influence thought and mood: (10)
- It provides more than 150 times more genetic material than the human genome itself (4, 10).
Why is the microbiota said to be unique?
Although all humans share a basic set of bacteria, each person's microbiota is distinct and variable (7,8). This composition is shaped by factors from birth (such as the type of delivery and breastfeeding) to current lifestyle and diet. (8)
How is it possible that gut bacteria influence my emotions?
There is a bidirectional system connecting the gut, the microbiota, and thought processes. (1,10) This system allows signals from the gut to influence the brain (modulating emotions, thought, and behavior). Bacteria act as a “metabolic machine” that produces key chemicals. (3,4) For example, serotonin (the feel-good hormone), GABA (which calms anxiety), dopamine (which motivates), and short-chain fatty acids (SCFAs) such as butyrate, which cross the blood-brain barrier to protect neurons and regulate inflammation. In turn, thought processes modulate basic intestinal functions such as motility, secretion of substances, and defense mechanisms. (4,9)
How do the microbiota, gut, and human brain communicate?
- This communication is bidirectional, from the microbiota to the gut and the brain, and with descending pathways from the brain to the gut.
What factors can alter the microbiota?
- Sleep disturbance: Sleep disruption and changes in the biological clock desynchronize the gut.
- Feeding: High consumption of complex carbohydrates, artificial sweeteners, diets high in fat, refined sugars.
- Smoking: Smoking changes the main families of the microbiota, although these tend to normalize when the smoking habit is quitted.
- Use of antibiotics: Antibiotics wipe out both good and bad bacteria, drastically reducing gut biodiversity. They should only be used under strict medical supervision.
What daily habits help maintain a healthy microbiota?
The good news is that small changes in routine can promote intestinal balance.
- Eat more fiber-rich foods: Eat onions, garlic, bananas, legumes, and whole grains. Fiber is fermented by your gut bacteria to produce fatty acids, which are important substances for maintaining emotional balance and improving brain development.
- Include fermented foods regularly: Yogurt, and products containing probiotics such as Lactobacillus and Bifidobacterium, can relieve symptoms of anxiety and depression.
- Regular exercise increases the diversity of species in your gut. Greater diversity means a more robust system capable of recovering faster from stress and infections.
- Sleep well: Sleep regulates stress-related hormones, which also impact the gut. Sleep deprivation alters the composition of the gut microbiota, affecting mental health.
- Stress management: Chronic stress weakens the intestinal barrier, allowing toxins to pass into the blood ("filtering gut"), which can alter emotions.
Can probiotics help with emotional well-being?
Probiotics are supplements or foods containing live microorganisms that support digestive health. In recent years, research has emerged on their potential impact on mental health. Clinical studies have observed improvements in indicators of emotional well-being and stress management.
What are the signs that may reflect support in the microbiota?
Some digestive signs:
- Abdominal distension or pain
- Changes in bowel habits
- Food intolerance
- Recurrent abdominal discomfort
- Changes in appetite
Emotional signals
- Mood swings
- sleep changes
- Lack of motivation
- Difficulty concentrating
These symptoms don't always have a single cause, but they can be a sign to review daily habits such as diet, rest, physical activity, and stress management. If these symptoms are frequent, it may be helpful to consult with healthcare professionals who can evaluate eating habits, lifestyle, and overall well-being.
At medical institutions like the Valle del Lili Foundation, specialists can guide people on how to improve their digestive health through lifestyle changes, clinical evaluations, or nutritional support. Your mental well-being begins with an informed decision about the care of that "invisible organ" you carry within you.
Today, the science of the gut-brain axis offers us an unprecedented opportunity to improve our emotional health and resilience to stress through strategic changes in nutrition, sleep, and exercise. We encourage you to view these habits not as mere general recommendations, but as a genuine biological intervention to restore your emotional and digestive balance.
If you experience persistent symptoms of anxiety, depression, or mental fatigue, we encourage you to seek a comprehensive evaluation that considers the health of your digestive system as part of the solution. Learning about your health is the first step; taking action with professional support is the path to cultivating an inner wellspring that sustains your happiness and mental clarity in the long term.
Reference Bibliography:
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