Why Would a Psychologist Write About Food and the Gut Microbiome?
Because the relationship between mind and body is not a metaphor—it is a lived, biological reality. As an integral psychologist and Core Energetics practitioner, my work is grounded in understanding how our psychological experience is inextricably linked to our physiology. The gut microbiome—the trillions of microorganisms inhabiting our digestive tract—plays a direct and profound role in shaping our mood, cravings, and even the fundamental way we relate to food. If we take seriously the notion that our minds do not exist in isolation from our bodies, then we must also take seriously the idea that what we eat—and more importantly, what our microbiome has been trained to expect—shapes our psychological landscape.
The Gut-Brain Axis: A Two-Way Conversation
Modern research has established that the gut and the brain are in constant communication via what is known as the gut-brain axis. This dialogue occurs through the vagus nerve, immune signaling, and the production of neurotransmitters such as serotonin and dopamine—many of which are manufactured not in the brain, but in the gut. This means that the microbiome has direct access to influence mood, cognition, and even decision-making processes related to food choices.
Microbiome Training: How Your Gut Shapes Your Cravings
When we talk about "training the microbiome," we mean that the microbial communities in the gut adapt to our habitual diets. The bacteria that thrive on the foods we regularly consume multiply, while those that would thrive on alternative diets diminish. This has a profound impact on cravings. Research has shown that the gut microbiota can influence dietary choices by signaling hunger for the foods that sustain them.
For example, a microbiome accustomed to high sugar intake may reinforce cravings for more sugar, whereas a microbiome shaped by fiber-rich whole foods may promote satiety and regulate glucose more effectively.
In a Proceedings of the National Academy of Sciences study, researchers demonstrated that gut bacteria could modulate diet selection in animal models by altering neurotransmitter production and amino acid availability. Similarly, human studies suggest that individuals who shift their diets—such as adopting plant-based eating or reducing processed foods—report altered cravings over time, a process that correlates with measurable shifts in their microbiome composition.
Psychological Implications: Who Is Really Choosing?
This leads to a fundamental question: how much agency do we truly have over our food choices? If our cravings are not entirely "ours" but rather co-constructed by the trillions of microbes that inhabit our gut, then any effort at changing eating habits must also include a transitional period in which the microbiome itself is reoriented. This has profound implications for behavior change models in psychology.
Traditional approaches to dietary change often frame cravings as a battle between willpower and indulgence. But if our gut bacteria are effectively lobbying for certain foods, then changing eating patterns isn’t just about psychological determination—it’s also about microbiome retraining. This suggests that the difficulty people experience in shifting their diet is not merely a failure of discipline but a deeper biological restructuring that requires time and support.
Beyond Food: Implications for Mental Health
Emerging research connects the gut microbiome not only to food cravings but also to broader mental health concerns. Anxiety, depression, and even certain personality traits appear to correlate with microbiome diversity. Studies show that individuals with higher levels of gut microbial diversity tend to report greater emotional resilience, while imbalances in gut flora have been linked to increased susceptibility to stress and mood disorders.
This reinforces what many of us in integrative health have long suspected: that dietary choices are not merely about physical health, but about mental well-being. When we work with clients who struggle with compulsive eating, food addiction, or emotional eating, we must consider that part of their struggle may stem from a microbiome trained by years—perhaps decades—of processed food, sugar, or inflammatory ingredients. Their gut bacteria are, in a very real sense, shaping their internal experience.
A Call for Integral Change
If we want to change our relationship with food, we must engage in a truly integral approach—one that recognizes the microbiome as both a physical and psychological factor. The gut-brain axis is a feedback loop that can be shifted, but doing so requires more than just individual willpower. It requires education, patience, and a reorientation of the entire gut ecosystem.
For those seeking to make dietary shifts, a gradual approach that includes prebiotics, probiotics, and fiber-rich whole foods can help recalibrate the microbiome. Somatic practices, mindful eating, and stress regulation techniques further support this process, helping to integrate biological and psychological change.
Final Thoughts
At its core, the science of the gut microbiome is telling us something profound: our body is not separate from our mind. What we feed ourselves—on every level—determines not just our physical health but the very nature of our inner world. And that is why a psychologist must write about food.
