The Person You Believe You Are is Making You Sick
Randy F.J. Laumen is a holistic health coach specializing in physical health, mental well-being, and identity-based lifestyle change. He is the co-founder of We The Fit People and the author of Your Metabolic Reset (2025), focused on restoring metabolic health and overcoming insulin resistance.
"I've always been a stressed person." "I'm just not someone who's good with food." "This is simply how my body is." These sound like harmless descriptions, honest self-knowledge, even humility. But they are not descriptions. They are instructions, and your body is listening to every one of them.
In the previous article, I argued that identity is the right tool for lasting health change, that when you shift who you believe you are, better behaviors follow. This is the harder, more uncomfortable half of that same truth. Because if a healthy identity can quietly lift you toward vitality, an unhealthy one can just as quietly hold you in decline. The story you tell about who you are is not neutral. It is shaping your physiology right now, whether you have chosen it consciously or not.
Belief is not just in your head
We like to imagine a clean border between mind and body, that beliefs live in one country and biology in another, and that what you think about yourself has no real bearing on your cells. The science says otherwise, and it says so with unusual clarity.
Consider the research of Stanford psychologist Alia Crum. In one landmark study, participants drank identical milkshakes, but some were told the shake was a rich, indulgent, high-calorie treat, while others were told it was a sensible, low-calorie drink. Their bodies did not respond to what they actually drank. They responded to what they believed they drank. Those who thought they were consuming the indulgent shake showed a dramatically steeper drop in ghrelin, the hunger hormone, as though their bodies had physically received more food. Same shake. Different belief. Different physiology.
It does not stop at hunger. Crum's wider body of work has shown that hotel workers who came to see their daily labour as meaningful exercise lost body fat and lowered their blood pressure without changing what they actually did, and that people taught to view stress as enhancing rather than harmful produced healthier cortisol responses under pressure. The belief was not a comforting story laid on top of the biology. The belief was a cause of the biology. Mindset, it turns out, is a physiological input as real as food or movement.
Now extend that principle from a single milkshake or a single afternoon to an entire identity held across decades. If believing something about one drink can measurably move your hormones, what is a lifelong belief about the kind of person you are doing to your body, day after day, year after year?
How the person you believe you are can make you sick
A fixed identity shapes your health through two channels at once, and they reinforce each other. The first is behavioral. The person who believes "I'm not a healthy person" does not make the small daily choices that a healthy person makes. Not because they lack information, but because those choices contradict their sense of self. Every unhealthy action confirms the identity, and the confirmed identity makes the next unhealthy action more automatic. The belief writes the behavior, and the behavior votes for the belief. Round and round, tightening.
The second channel is more direct, and it runs through the body's stress physiology. The person who is certain "I've always been a stressed person" lives in a nervous system braced for threat. A chronically activated hypothalamic-pituitary-adrenal (HPA axis,) elevated cortisol, disrupted sleep, and all the metabolic consequences that flow from them. Their identity is not merely describing their stress. It is instructing their body to keep producing it. They are, in the most literal biological sense, living up to who they believe they are.
This is where my two fields meet most sharply. As a psychiatric nurse, I have watched people defend a diagnosis or a self-image long after it stopped serving them. As a practitioner working with metabolism, I have seen the physical toll of that defence, the weight that will not move, the fatigue that will not lift, and the markers that drift in exactly the direction the person's self-story predicts. The mind holds the belief. The body pays the bill.
Why we cling to the identity that harms us
Here is the question that unsettles people, and it is the right one to sit with: if an identity is making us sick, why on earth would we hold on to it?
The psychiatrist Alfred Adler offered an answer more than a century ago that remains, in my experience, the most useful lens available. Adler proposed that we do not simply inherit our self-concepts, we adopt them, often early, because they serve a purpose. An identity, even a limiting one, offers something: safety, predictability, an explanation, and above all, protection from responsibility and from the risk of failure.
"I've always been this way" is a sentence that closes a door, and behind that closed door it is warm and safe. If this is simply who I am, then I do not have to attempt the frightening, uncertain work of change. I do not have to risk trying and failing. I do not have to face who I might have to become. The unhealthy identity is not only a burden. It is also, quietly, a shelter. That is precisely why it is so hard to put down, and why willpower alone never touches it. You cannot force your way out of a shelter you are still using.
This is not a comfortable idea, and I do not offer it as a comfortable one. But it is, in my clinical experience, a liberating one. Because the moment a person recognizes that their identity is a choice they have been making, not a fixed fact they are stuck with, the door they thought was locked turns out to have been closed only from the inside.
You are not stuck with who you have been
Let me be careful and precise here, because this territory invites misunderstanding. I am not saying that belief alone causes disease, or that you can think your way out of a serious illness. Genetics, environment, circumstance, and plain misfortune are all real, and none of them are anyone's fault. To suggest otherwise would be both false and cruel.
What I am saying is narrower and, I think, more useful: that among all the forces shaping your health, the story you tell about who you are is one of the most powerful, one of the most overlooked, and crucially, one of the most within your power to change. You do not get to choose your genes. You do have some say over the identity you inhabit. That identity is not a spectator to your health. It is a participant.
The person who begins to believe "I am someone who is becoming healthier" starts, in small and measurable ways, to become exactly that. Through the choices the new identity makes natural, and through a nervous system that slowly stops bracing for a threat that the old story kept insisting was there. The same mechanism that held them in decline can, once turned, begin to lift them out of it.
Listen to the instructions you are giving
So listen, honestly, to the way you talk about yourself. Not the grand declarations, but the small automatic ones, the throwaway lines about the kind of person you are, the things you have "always" been, the way your body "just is." These are not innocent observations. They are the standing instructions your body has been dutifully carrying out, perhaps for most of your life.
The person you believe you are may indeed be making you sick. But that sentence contains its own remedy, because if the person you believe you are can shape your health, then becoming a different person, deliberately and honestly, is not wishful thinking. It is one of the most concrete medical interventions available to you. Unlike almost everything else in healthcare, this one begins the moment you decide to change the story.
Change the story, change the body
If you sense that an old story about who you are has been quietly shaping your health, holding you somewhere you no longer want to be, you do not have to untangle it alone.
At We The Fit People, our Body-Mind-Identity approach works at exactly this level. We help you see the identity you have been living from, understand what it has been costing your body, and build, deliberately and sustainably, the self from which real health can finally flow. This is the deepest work we do, and the most transformative.
Book a consultation today and let's change the story your body has been living by.
Read more from Randy Franciscus Johannes Laumen
Randy Franciscus Johannes Laumen, Holistic Health Coach
Randy F.J. Laumen is a psychiatric nurse and an emerging voice in the health space, focused on preventing chronic illness before it takes root. With a background in mental health and applied training in Functional Medicine, Cognitive Behavioral Therapy, and lifestyle-based interventions, he bridges the gap between conventional care and long-term well-being. Together with his wife, Sabrina Gutierrez, he co-founded We The Fit People, a platform dedicated to empowering individuals to take responsibility for their health. He is also the author of Your Metabolic Reset (2025), available on Amazon.
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