Gastrointestinal function and psychological state of an individual is one of the most crucial links in modern biological science that explains the influence of gut bacteria and its relevance. Human Gut consists of trillions of microorganisms, including bacteria, fungi, and viruses, resides primarily in the large intestine and has profound / measurable impact on both physical and mental health. This internal ecosystem serves as a metabolically active organ that constantly communicates with the central nervous system, affecting immune responses, micronutrients digestion (like Vitamin K & several B-complex) metabolic activities, and even emotional control, making the gut our second brain.
The Gut-Brain Axis: Bidirectional Communication
The connection between the gastrointestinal tract and the brain is a bidirectional route famously known as the gut-brain-axis, and is composed of immunological, neuronal, and neuroendocrine pathways.
Gut microbiota modulates the synthesis and functioning of neurotransmitters and any disruption of the gut microbiota (composition or function) is associated with many mental disorders, such as schizophrenia, depression, and other psychiatric disorders [1].
Perhaps most striking is the role of the gut in neurotransmitter production. Research indicates that approximately 90–95% of the body’s serotonin (the neurotransmitter critically involved in mood regulation, sleep, and appetite) is synthesized in the gastrointestinal tract. This physiological reality underscores a fundamental principle: gastrointestinal health and mental well-being are inextricably linked.
Is Your Gut Trying to Tell You Something?
An imbalanced gut rarely affects digestion alone. Persistent symptoms such as bloating, abdominal discomfort, irregular bowel movements, heartburn, unexplained fatigue, sugar cravings, skin issues, and changes in mood like anxiety or irritability may all signal an unhealthy gut microbiome. Rather than dismissing these symptoms as isolated concerns, they should be viewed as potential indicators of microbial imbalance, highlighting the need for a more personalized understanding of gut health.
The Indian Scenario: What the Numbers Tell Us
The relevance of the gut-brain connection is particularly pronounced in the Indian context, where both digestive and mental health disorders are increasingly prevalent.
A 2022 pan-India survey by Healthians, the ‘GUTpunch’ report, revealed that approximately 56% of Indians report poor digestive health, with lifestyle factors identified as primary contributors [2].The mental health burden is equally substantial. A 2020 study published in ‘The Lancet Psychiatry’ found that in 2017, 197.3 million people in India had mental disorders, including 45.7 million with depressive disorders and 44.9 million with anxiety disorders [3]. The contribution of mental disorders to the total disease burden in India increased from 2.5% in 1990 to 4.7% in 2017, with emerging research establishing links between these conditions and gut dysbiosis [3].
Recent analyses of Indian dietary patterns indicate that many households consume inadequate amounts of fruits, vegetables, legumes, and other nutrient-dense foods, while processed food consumption has steadily increased. This shift away from traditional, fiber-rich dietary habits may adversely affect the gut microbiome, as dietary fiber is the primary fuel for beneficial bacteria that produce short-chain fatty acids essential for gut integrity, immune regulation, and gut–brain communication. Diets dominated by processed foods and low in fiber are associated with reduced microbial diversity and diminished production of these protective metabolites [4].
Importance of gut microbiome testing
Advances in metagenomic sequencing have enabled comprehensive analysis of the gut microbiome test through a simple, non-invasive stool sample. For example, tests based on Whole Metagenome Shotgun Sequencing (mNGS) can identify over 2,000 microbial species, including bacteria, fungi, viruses, and archaea, providing a detailed snapshot of the gut microbial ecosystem. Such tests can assess 15+ gut health functions, screen 40+ key probiotic strains and 50+ clinically relevant pathogens, evaluate microbial diversity and short-chain fatty acid (SCFA)-producing bacteria, and identify markers associated with antibiotic resistance. Together, these analyses help characterize both the composition and functional capacity of the gut microbiome, enabling personalized dietary and lifestyle recommendations to support long-term gut health.
Conclusion
The human gut is much more than just a digestive organ; through the gut-brain axis, it continuously communicates with the brain and plays a significant role in overall health. It is more crucial than ever to comprehend this relationship as India experiences an increase in digestive and mental health issues brought on by shifting lifestyles. Instead of just treating symptoms, a gut microbiome test provides insightful information about the distinct microbial population that can guide dietary and lifestyle decisions.
‘After all, a healthier gut doesn’t just improve digestion, it lays the foundation for better physical health, sharper minds, and a healthier future.’
References
1. Abstracts: 11th Asian Veterinary Ophthalmology Annual Conference, Taipei City, Taiwan, October 21-22, 2023. (2024). Veterinary ophthalmology, 27(2), e1–e24.
https://doi.org/10.1111/vop.13181
2. Healthians. (2022). The GUTpunch report: Mapping the state of gut health in India. Healthians Research Division. India State-Level Disease Burden Initiative Mental Disorders Collaborators. (2020). The burden of mental disorders across the states of India: The Global Burden of Disease Study 1990–2017. The Lancet Psychiatry, 7(2), 148–161.
https://doi.org/10.1016/S2215-0366(19)30475-4
3. Berding, K., Vlckova, K., Marx, W., Schellekens, H., Stanton, C., Clarke, G., Jacka, F., Dinan, T. G., & Cryan, J. F. (2021). Diet and the microbiota–gut–brain axis: Sowing the seeds of good mental health. Advances in Nutrition, 12(4), 1239–1285 . https://doi.org/10.1093/advances/nmaa181
4. Hirvonen, K., Bai, Y., Headey, D., & Masters, W. A. (2020). A comparison of the Indian diet with the EAT-Lancet reference diet. BMC Public Health, 20, 812. https://doi.org/10.1186/s12889-020-08951-8
