Hüseyin Nazlıkul Breaks the Mold Again: The Boundaries of Your Emotional Brain
Bloating, fatigue, insomnia, brain fog, anxiety, hormonal disorders… Is this picture, which modern people consider "normal," actually the body's cry for help? Prof. Dr. Hüseyin Nazlikul, with his new books "Emotional Brain-Gut II" and "I Can't Sleep," is fundamentally shaking up our view of illness.
Prof. Dr. Hüseyin Nazlikul answered Odatv's questions in a special interview about his books "Emotional Brain-Gut II" and "I Can't Sleep."
Why is the gut the "emotional brain"? Why is insomnia the biological protest of our age? An interview much will be said about, on neural therapy, the vagus nerve, the microbiota, electromagnetic pollution, and poetry's place in medicine…
Nazlikul explained why the gut is not merely a second brain but an "emotional brain," why insomnia has become a biological objection to modern life, and how the body wants not to be silenced, but to be listened to:
'TODAY WE ARE NOT EXPERIENCING ILLNESS, BUT A COLLAPSE OF REGULATION'
Question: Two powerful books at the same time: "Emotional Brain-Gut II" and "I Can't Sleep." Why now, why these two books?
Because the picture we encounter in our clinical practice today is not an "age of diseases" in the sense defined by classical medicine. What we are increasingly experiencing today is a holistic collapse of bodily regulation. People come in with numerous test results; often their imaging is acceptable, their blood values are within range. But despite this, they are not well. They can't sleep, can't digest, can't recover, they lose their mental clarity, their hormonal and emotional balance is disrupted. In other words, the problem is not in individual organs, but in the organism's own capacity to self-regulate.
I wrote these two books together precisely for this reason. "Emotional Brain-Gut II" explains, in a multilayered set of relationships extending from the microbiota to the nervous system, from immunity to emotions, how the intestinal system — located at the center of the body, right in the middle of the regulatory network — has collapsed. "I Can't Sleep," on the other hand, reveals at what point this collapse is turned by the body into a state of alarm. Because my clinical observation shows this very clearly: healthy sleep is not disrupted without gut regulation being disrupted first; the hormonal axis does not permanently collapse without sleep being disrupted; and mood, immunity, sexuality, and even personality structure are not affected without the hormonal axis collapsing. Most of the conditions we encounter today — chronic fatigue, infertility, autoimmune diseases, depression, IBS, brain fog — are not separate diseases, but breaking points in different links of the same regulatory chain. These two books were written precisely to make this chain visible: one shows where the system began to collapse, the other shows where it can no longer hold.
'THE GUT IS NOT A SECOND BRAIN, IT IS THE EMOTIONAL BRAIN'
Today, the gut is still often treated as merely a digestive organ. Yet the gut is the center of the immune system, the arena of hormonal transformation, the ecosystem of the microbiota, and one of the densest networks of the autonomic nervous system. But for me, the matter goes beyond even this. What I've seen in my clinical practice for years is that the gut is not merely a structure containing neurons; the gut is also the biological stage for emotional burdens, suppressed reactions, and unresolved traumas.
A person does not only digest what they eat. A person also digests what they experience. And what cannot be digested most often accumulates in the gut. Long-suppressed anger alters colon motility, chronic fear and distrust disrupt the microbiota, unresolved grief lowers vagal tone and increases intestinal permeability. I see every day in my patients that trauma, stress, and emotional burden are not merely psychological matters, but a direct biological reality.
This is why I find the term "second brain" insufficient. "Second brain" is a technical definition. But the picture we face today is not technical — it is existential. I see the gut as the biological map of a person's relationship with life, of what they carry, and of what they cannot cope with. That is why I call it the "emotional brain." Because when the gut is disrupted, it is not only digestion that is disrupted; sleep is disrupted, the hormonal axis goes off course, the immune system loses its direction, sexual and reproductive functions are affected, and mental clarity and emotional balance are shaken. "Emotional Brain-Gut II" describes exactly this: not where the disease begins, but where a person's regulation and inner wholeness begins to dissolve. "I Can't Sleep," meanwhile, shows how this dissolution is now turning into an explicit biological call from the body.
'A PERSON DOES NOT ONLY DIGEST WHAT THEY EAT, THEY ALSO DIGEST WHAT THEY EXPERIENCE'
Question: In your book, you place particular emphasis on "emotional brain" instead of "second brain." Why?
Because the gut is not merely a second nervous network containing millions of neurons; the gut is also a biological memory field that carries what a person has experienced, suppressed, and the emotional burdens they cannot resolve. What I have seen in my clinical practice for years is this: a person does not only digest what they eat, they also digest what they experience. And what cannot be digested is most often held in the gut. Fear, suppressed anger, long-term stress, unresolved grief, traumatic experiences… A significant portion of these are reflected over time in intestinal motility, mucosal structure, the microbiota, and immune responses.
It is not possible to explain the significant increase we see today in dysbiosis, histamine intolerance, irritable bowel syndrome, autoimmune diseases, and functional digestive disorders through dietary errors alone. Of course diet is important, toxins are important, environmental factors are important; but the broad picture we see shows that a person's emotional-burden metabolism has broken down. In other words, the body has become unable to regulate not just sugar, fat, and gluten, but also stress, fear, unresolved grief, and suppressed anger.
In this sense, the gut is not merely a physiological organ, but the biological mirror of a person's relationship with life. Long-suppressed emotions alter vagal tone, transform the microbiota, increase intestinal permeability, and put the immune system into a state of chronic alarm. For this reason, when the gut is disrupted, it is not only digestion that is disrupted; sleep is disrupted, hormonal balance goes off course, immunity weakens, emotional tolerance drops, and even the way a person relates to the world changes.
This is why I do not find the term "second brain" sufficient. Because "second brain" is a neurological definition, whereas the picture we face today is not merely neurological but also emotional, existential, and regulatory. I see memory in the gut, I see burden, I see unresolved stories. That is why I call it the "emotional brain." Because the gut carries not only what a person has digested, but also what they have failed to digest.
And "Emotional Brain-Gut II" was written precisely starting from this point: not to describe which organ the disease appears in, but to explain which inner wholeness a person has lost.
'INSOMNIA IS NOT A SYMPTOM, IT IS THE BIOLOGICAL PROTEST OF OUR AGE'
Question: In your book "I Can't Sleep," you define insomnia not merely as a problem but as a "signal." Why is being unable to sleep so critical, in your view?
Because sleep is not merely a period of time in which a person rests; sleep is a biological "renewal field" in which the organism repairs itself, the nervous system is recalibrated, hormones are rewritten, and immunity finds its rhythm again. When a person cannot sleep, they don't just become unable to close their eyes; the body's capacity to repair itself is disrupted, and over time this turns into a regulatory disorder that spreads to all systems. For this reason, I find it insufficient to simply call insomnia a "sleep disorder." Being unable to sleep is often not a single symptom, but an alarm given by the body, and, more importantly, a biological protest it has developed against our way of life.
Today, as a society, we are experiencing a very pronounced loss of rhythm. The boundary between night and day has been erased; screen light, artificial lighting, a constant state of stimulation, eating late at night, chronic stress, and the necessity of living with uncertainty keep the nervous system in an "always on" mode. From the perspective of the autonomic nervous system, this resembles a situation in which sympathetic dominance never ends during the day and never shuts down at night. In other words, when night comes, the body cannot switch to the parasympathetic side and begin "repair"; it remains on alert, because it still carries a perception of threat. This is often at the center of insomnia: the body's inability to feel safe. A body that cannot feel safe cannot surrender to sleep.
'THE MATTER IS NOT MERELY PSYCHOLOGICAL'
Moreover, the matter is not merely psychological; this picture is also very concrete biologically. With insomnia, the cortisol rhythm is disrupted, melatonin secretion weakens, mitochondrial energy production drops, inflammation increases, insulin resistance becomes easier, and gut flora is further disrupted. In other words, after a while, being unable to sleep turns into a self-perpetuating vicious cycle: as the gut is disrupted, sleep is disrupted; as sleep is disrupted, the gut is disrupted even further; the hormonal axis goes off course, emotional tolerance decreases, immunity becomes fragile. A person doesn't just wake up tired one morning; over time, they wake up "far from being themselves." Because sleep produces not only energy, but also identity and balance.
This is why in the book "I Can't Sleep" I try to explain the following: instead of seeing insomnia as a problem to be immediately silenced, we need to read it as a language. The body is telling us something. It is saying, "This pace is not for me." It is saying, "This light, this noise, this stress, this electromagnetic pollution, this undigested emotion, this burden I carry... I cannot repair myself within all of this." In this sense, insomnia is one of the clearest responses the body gives against modern life's disconnection from what is natural.
For me, "I Can't Sleep" is not merely a book that explains sleep hygiene. This book is a roadmap that calls the reader back to their own rhythm, teaches how to re-regulate the nervous system, and treats sleep not as "a process to be suppressed with a pill" but as a biological order to be rebuilt. Because when sleep returns, it is often not only sleep that returns; mental clarity, hormonal balance, immune strength, and emotional resilience return along with it.
'HUMANS HAVE LOST THEIR RHYTHM'
Question: Your book "I Can't Sleep" directly concerns a much broader audience. Why do you think we are so sleep-deprived today?
Because humans have lost their rhythm.
Light pollution, screens, electrosmog, nighttime meals, the language of fear, uncertainty, a constant state of alertness…
Sleep is the time when the nervous system repairs itself.
But today, the nervous system is under threat even at night.
I now see insomnia not as a disease,
but as the body's objection to this way of life.
The body is saying:
"At this speed, in this magnetic noise, at this level of stress, I cannot repair myself."
'I DON'T LOOK AT ORGANS, I LOOK AT THE ORGANISM'
Question: The books present a framework that goes far beyond the classical narrative of medicine: the vagus nerve, the microbiota, the ECM, mitochondria, the electromagnetic field… What are you actually fighting against?
Against the fragmented understanding of the human being.
Today, one person deals with the gut, another with hormones, another with psychology, another with sleep, each separately.
Yet the body is a field system.
If the gut is disrupted, it's not just the colon that's disrupted.
Brain fog occurs.
Sleep flees.
Hormones go off course.
Connective tissue becomes overloaded.
Mitochondria grow tired.
Emotions cannot regulate themselves.
I don't treat organs.
I try to regulate the organism.
'SOME ILLNESSES ARE RESOLVED NOT WITH KNOWLEDGE, BUT WITH EMOTIONAL RESONANCE'
Question: There is a striking novelty in both books: poems. Why poetry in a medical book?
Because some biological doors cannot be entered through the cortex.
Poetry enters the limbic system.
Poetry touches the vagus.
Poetry is the language of the nervous system.
Some illnesses are resolved not with knowledge, but with emotional resonance.
These poems are not decoration.
These are texts written for the nervous system.
Science teaches.
Poetry regulates.
'INVISIBLE POLLUTION IS THE MOST DANGEROUS'
Question: Electrosmog and the magnetic field occupy a special place in "I Can't Sleep." Why?
Because for the first time in the history of human evolution, people are living outside the natural magnetic field.
Melatonin is sensitive to the magnetic field.
Mitochondria are sensitive.
The autonomic nervous system is sensitive.
The rise in insomnia, distractibility, early puberty, and immune collapse in children is not a coincidence.
Invisible pollution
is the deepest biological pollution.
'THESE BOOKS ARE NOT FOR TREATMENT, BUT TO SPARK AWARENESS'
Question: What do you expect to change in the reader's life after these two books?
Three things:
• Perception of the body
• Perception of illness
• The rhythm of life
If the reader begins to say the following, the book has achieved its purpose:
"I am not sick, I am unregulated."
"I am not sleepless, I am arrhythmic."
"I don't just have a stomach problem, I cannot digest my life."
The moment this sentence is formed, treatment begins.
'THESE BOOKS ARE NOT TREATMENT, BUT A THRESHOLD OF AWARENESS'
Question: What do you expect to change in the reader's life after these two books?
I want three things to change fundamentally:
The perception of the body, the perception of illness, and the rhythm of life.
Today people look at their bodies like a machine.
Like a system whose parts get replaced when broken, that falls silent when suppressed, that gets silenced with medication when tired…
But the body is not a machine.
The body is a memory field, a rhythm system, and a regulatory intelligence.
These books were not written to say "this is what that disease is."
These books were written so that a person can, for the first time, truly look at their own body.
When the reader begins to say the following, the books have achieved their purpose:
"I am not sick, I am unregulated."
"I am not sleepless, I have lost my rhythm."
"I don't just have a stomach problem, I cannot digest my life."
Because the moment these sentences are formed, a very critical threshold is crossed.
Responsibility shifts from illness to life.
It shifts from organs to the organism.
It shifts from suppression to understanding.
A person no longer asks, "Which medication should I take?"
They begin to ask:
"What am I unable to hear?"
"What am I unable to digest?"
"What speed, what fear, what burden am I living within?"
This is exactly where treatment begins.
Before the prescription, comprehension begins.
Before the injection, awareness begins.
Before the supplement, rhythm begins.
This is why these books are not "treatment books," but books of awakening.
They are a call to reconnect with the body.
A call to make peace with sleep.
A call to reconnect with the gut, with breath, with the vagus, with emotion.
Because I believe this:
Illness is often not an enemy, but a language.
And we have been mistranslating this language for a long time.
The moment this sentence is formed, treatment begins:
"My body is telling me something."
And at that moment, a person, for the first time, truly sets out on the path to healing.
'THIS IS NOT A BOOK DEAL, BUT A LONG-TERM COMPANIONSHIP'
Question: These two books of yours are reaching readers under the İnkılap Kitabevi Publications and Üçüncü Göz Publications label. How did this partnership begin? Is it limited to just these two books?
Actually, this partnership was not a snap decision.
We're talking about a process that dates back to before the pandemic, that has been discussed for a long time, and that has unfolded gradually over time.
Our contact with İnkılap Üçüncü Göz Publications did not begin simply with "let's publish two books." It began more with the question:
"What can we leave behind for society in the long term?"
"How can we bring science, the body, emotion, and the human inner world together under the same roof?"
For this reason, I see this collaboration not so much as a publishing agreement, but as a publishing journey.
The Emotional Brain-Gut II and I Can't Sleep, published now, are the first steps of this journey.
Next will come my book titled "Longevity – A Regulated Life." In this book, I address healthy longevity from a holistic perspective extending from the cell to the nervous system, from nutrition to rhythm, from consciousness to regulation.
But this path is not limited to medical books alone.
I have long been immersed in poetry.
Because you cannot describe a human being through biology alone.
Sometimes a single line says more than an MRI scan.
My first poetry book, "On the Threshold of Loyalty" (Vefanın Eşiğinde), will be a book of gratitude to all the mentors, teachers, and companions who have added value to me, and to life itself.
That will be followed by my book "Meditation," which has been at the center of my life since I was 14 years old, shaped by inspiration from Erich Fromm. This book will be a philosophical, biological, and existential text all at once.
In other words, the bond we have formed with İnkılap Üçüncü Göz has turned into a long-term project of at least five books, extending into non-medical fields as well, touching both the cell and the soul of human beings.
I would especially like to thank Aren Şenorkyan and Gülşen İşeri, who put in great effort in opening these doors, shaping this vision, and building this partnership with such enthusiasm.
This approach, which sees publishing not merely as printing but as content and companionship on a journey, is very valuable to me.
For this reason, I can comfortably say:
This is not a "two-book period,"
but a multilayered body of work being built together.
'THE BODY DOES NOT LIE'
Question: Finally… If you were to summarize these two books in a single sentence?
"Emotional Brain-Gut II" describes where a person collapses.
"I Can't Sleep" describes where a person can no longer hold on.
One writes the biology of collapse.
The other, the night of exhaustion.
And together, they say this:
The body does not lie.
But we have not been listening to it for a long time.
Because the language of the body is loud.
It speaks through pain.
It whispers through insomnia.
It gives voice through bloating, palpitations, the skin, the gut, sexuality, forgetfulness.
Modern people think this language is a "malfunction."
But the body most often does not malfunction.
It gives a warning.
It says, "This pace is not for me."
It says, "This life is too heavy for me."
It says, "You have been carrying this emotion for years."
It says, "This fear is in your gut, this anger is in your diaphragm, this loneliness is in your sleep."
But what do we do?
We silence it.
We suppress it.
We name it and push it away.
These two books were written precisely for this reason.
So that people can listen to their bodies again.
So that instead of fighting the symptom, they can decipher the message.
So that they can see rhythm before sleeping pills,
emotion before probiotics,
and life before hormones.
These books claim the following:
The body does not break down.
The body carries a burden.
And one day, that burden begins to speak.
If you too have recently been saying,
"I'm not like I used to be,"
"I rest but I don't get better,"
"My test results are normal but I am not well"…
These two books were written for you.
Because these books don't describe illness.
They describe the human being.
And perhaps most importantly, they remind us:
Healing often begins not with a treatment, but with a realization.
The body does not lie.
The question is:
Are we ready to truly listen to it?