Gut Environment and Serotonin
wpmasterIntroduction
Serotonin, often called the “happiness hormone,” plays a role in mood stability, sleep, and digestion. According to Japan’s Ministry of Health, Labour and Welfare (MHLW), over 90% of serotonin in the body is produced in the gut.
Facts about Gut and Serotonin
MHLW e-Health Net states:
“Serotonin exists not only in the brain but also abundantly in the gut, where it regulates intestinal motility.”
Source: MHLW e-Health Net – Serotonin
This shows that serotonin is not limited to the brain but is also abundant in the gut, supporting digestive function. When the gut environment is disturbed, serotonin production and function may also be affected.
WHO emphasizes the importance of mental health:
“Mental health is an integral part of health; indeed, there is no health without mental health.”
Source: WHO – Mental health: strengthening our response
This statement highlights that gut-derived serotonin is closely tied to overall health. Although serotonin produced in the gut does not directly reach the brain, it influences mental states indirectly through the gut-brain axis.
PubMed abstract notes:
“Gut microbiota influence serotonin systems, affecting host physiology and behavior through the gut-brain axis.”
Source: PubMed – Gut microbiota influence on serotonin system
This research confirms that gut microbiota regulate serotonin metabolism and thereby affect mood and behavior.
Habits to Support Gut and Serotonin
- Consume fiber and fermented foods to balance gut microbiota.
Source: WHO – Mental health: strengthening our response - Eat tryptophan-rich foods such as bananas, dairy, soy products, and eggs.
Source: MHLW e-Health Net – Serotonin - Exercise moderately to stimulate gut motility and stabilize serotonin release.
Source: PubMed – Gut microbiota influence on serotonin systems - Maintain a regular lifestyle and morning light exposure to support serotonin synthesis.
Source: WHO – Mental health: strengthening our response
Conclusion
Gut health is deeply connected to serotonin production, influencing both digestion and mental well-being. MHLW highlights the abundance of serotonin in the gut, WHO emphasizes the inseparability of mental and physical health, and PubMed research demonstrates how gut microbiota regulate serotonin systems. Together, these sources show that diet, exercise, and lifestyle habits are essential for maintaining both gut and mind health.
