Let’s embark on a story that stretches across billions of years, linking the smallest life forms on Earth—bacteria—to the intricate workings of the human brain. Our journey begins four billion years ago, when Earth was unrecognizable from the lush, vibrant planet we inhabit today. There was no oxygen, no plants, no animals, and certainly no humans. But there was water, and in that water, life took its first breath in the form of bacteria.
These early pioneers ruled the Earth alone for billions of years, forming complex, collaborative societies. Imagine them as tiny chemical factories, each specializing in transforming one substance into another, living in intricate ecosystems where cooperation was key to survival. They colonized extreme environments: thriving in deep-sea vents, crusting the shores of primordial lakes, and eventually laying the foundation for all life that followed—plants, animals, and, ultimately, us.
A shared world
Despite our illusions of dominance, humans are recent guests on this bacterial planet. From the moment life began, bacteria have shaped ecosystems, species, and evolution itself. We, like all living beings, are deeply intertwined with them. They live on us, in us, and with us—partners in an unbroken biological symbiosis that has endured for millennia.
Take a closer look at your body. Bacteria thrive on your skin, in your nose, in your mouth, and even in the most intimate parts of your anatomy. But their true kingdom lies within: the gut microbiome, a teeming jungle of bacteria, fungi, viruses, and other microorganisms. It’s a bustling metropolis of life, with each species playing a role in digestion, immunity, and even mental health.
Birth of a microbiome
The story of our relationship with bacteria begins the moment we’re born. A baby in the womb is sterile, free of microbes. But during a vaginal birth, the baby is “gifted” lactobacillus bacteria from its mother, a crucial first step in forming a healthy microbiome. Breast milk further nourishes these bacteria, providing specialized sugars designed not just for the baby but for its gut bacteria too. It’s as if evolution knew that nurturing this microscopic world was just as vital as feeding the infant itself.
This symbiosis is no accident. The baby’s microbiome matures over the first three years of life, a period that coincides perfectly with the rapid development of the brain. The gut and brain grow together, shaping each other in ways we’re only beginning to understand. Experiments in rodents reveal that an underdeveloped microbiome can lead to abnormal brain development, affecting behaviour, learning, and emotional regulation.
When the microbiome is disrupted
But what happens when the microbiome doesn’t develop as it should? In humans, disruptions can occur due to caesarean births, lack of breastfeeding, or early exposure to antibiotics. These children often face higher risks of allergies, autoimmune diseases, obesity, and even mental health challenges such as ADHD or autism later in life. It’s a stark reminder of how vital this bacterial partnership is to our health and well-being.
Feeding your microbial garden
As we grow, the microbiome continues to play a central role in our health. A diverse and thriving microbiome supports digestion, strengthens the immune system, and even produces compounds that benefit the brain. But like any ecosystem, it requires care. Feeding your microbiome means feeding yourself well. Nutritional fibres found in fruits, vegetables, and whole grains act as food for your gut bacteria, helping them flourish.
Fermented foods like yogurt, sauerkraut, and kimchi are rich in probiotics, introducing beneficial bacteria directly into your gut. On the other hand, processed foods, alcohol, and preservatives can harm the microbiome, reducing its diversity and resilience. A diet rich in diverse, whole foods is not just a recipe for good health—it’s an act of love for the bacteria that keep you alive.
The Gut-Brain connection
The relationship between the gut and the brain is profound. Gut bacteria help produce neurotransmitters like serotonin, which regulates mood, and GABA, which promotes calmness. Studies even show that gut bacteria can influence stress resilience. When your microbiome thrives, it supports not just your physical health but your emotional and mental well-being.
When bacteria protect the mind
In times of stress, the gut microbiome plays a protective role. For example, certain bacteria can prevent stress-induced inflammation that otherwise contributes to depression and anxiety. This connection has been studied in medical students during high-pressure exams. Those who consumed bacteria-rich beverages experienced fewer stress-related symptoms, including better sleep and fewer abdominal complaints. It’s a powerful testament to the role of the microbiome in navigating life’s challenges.
Aging, disease, and the microbiome
As we age, our microbiome changes, becoming less diverse. This decline is linked to conditions like Parkinson’s disease, where the gut often shows signs of illness before the brain. In diseases like Alzheimer’s, bacteria may trigger harmful immune responses in the brain. Even aging itself may be influenced by the microbiome, with studies in animals suggesting that a youthful microbiome can slow aging and extend life.
A relationship in crisis
Despite its importance, our relationship with bacteria is under threat. Pesticides, antibiotics, and processed foods have diminished the diversity of our microbiomes. Refrigeration, while convenient, has led to a decline in fermented foods in our diets. These modern practices disrupt a partnership that sustained our ancestors for millennia, leaving us more vulnerable to physical and mental health challenges.
A hopeful future
But there’s hope. The rise of interest in probiotics, fermented foods, and plant-based diets suggests we may be turning a corner. By choosing to nurture our microbiomes, we can reclaim not just our health but also a connection to the natural world. It’s a small but profound way to honour the legacy of life on Earth.
A shared legacy
Our relationship with bacteria extends to the end of life, where the microbiome ensures our remains are recycled into fertile soil, fostering new life. This poetic cycle highlights the interconnectedness of all life forms, bound together by the microbial world.
By nurturing our microbiome with a balanced diet and mindful choices, we not only enhance our physical and mental health but also honour the ancient symbiosis that has shaped life on Earth for billions of years. So, the next time you sit down for a meal, remember—you’re feeding more than just yourself. You’re nourishing the bacteria that help make you, you
References:
Sommer, I. (n.d.). The Bacteria and the Brain: The Influence of Your Gut Flora on Brain Health. [Translated from Dutch: De bacterie en het brein: De invloed van je darmflora op de gezondheid van je hersenen].
Calder, P. C., Ortega, E. F., Meydani, S. N., Adkins, Y., Stephensen, C. B., Thompson, B., & Zwickey, H. (n.d.). Nutrition, Immunosenescence, and Infectious Disease: An Overview of the Scientific Evidence on Micronutrients and on Modulation of the Gut Microbiota.
By Ampara Bouwens
Ampara is an experienced Clinical Psychologist with over 19 years of experience, providing mental health services in private, governmental, and corporate sectors. She specializes in complex trauma, personality disorders, and other severe disorders, using a compassionate and non-judgmental approach to help clients regain control and autonomy over their lives. Since moving to New Zealand in 2016, Ampara has been running a successful private practice, offering personalised and effective treatment to individuals seeking to improve their mental health and well-being. Ampara is also the clinical lead and founder of MindGarage – a leading provider of psychological services, treatment, and assessment, with a team of skilled therapists who provide high-quality, personalised treatment via the same compassionate, non-judgmental approach. The MindGarage team takes a holistic approach to therapy, considering all aspects of a client’s life and offering tailor-made services to meet individual needs. MindGarage believes in empowering clients with the skills and knowledge needed to make positive changes in their lives, promoting long-term mental and emotional health.
Visit Ampara online: https://mindgarage.co.nz/