We live in a paradoxical era. Medical knowledge has never been more advanced. Diagnostic technologies have never been more precise. And yet chronic diseases keep spreading — persistent fatigue, hormonal imbalances, digestive disorders, diffuse inflammation, depression. Not because medicine is failing, but because it is answering a different question than the one the body is actually asking.

Conventional medicine excels at treating crises, emergencies, and acute conditions. It has built extraordinary knowledge about diseases. But it struggles to answer this fundamental question: why does this particular body, in this particular context, at this particular moment, fail to maintain its equilibrium? This is precisely the question that functional health — and at its heart, PERMANUTRITION — seeks to answer.

Functional Health: A Different Way of Reading the Body

Functional health is not alternative medicine. It is terrain medicine, a medicine of deep causes, which seeks to understand how an organism functions as a whole — before seeking to suppress a symptom.

It is part of what is called 4P medicine: Preventive, Predictive, Personalized and Participatory. A medicine that anticipates rather than repairs, individualizes rather than standardizes, and places the patient as the central actor of their health — not as a passive recipient of treatment.

Concretely, this means:

• Not treating insomnia, but understanding why cortisol is still elevated at 2am.
• Not suppressing inflammation, but identifying what is sustaining it — diet, microbiome, chronic stress, environmental toxins.
• Not “balancing hormones” with an external treatment, but restoring the conditions in which the body can self-regulate.

Functional health works on the terrain — that biological, metabolic and emotional soil in which imbalances take root or resolve.

PERMANUTRITION: Nourishing the Terrain in Its Totality

Food is not fuel. It is information. Every bite sends signals to your genes, your microbiome, your hormones, your nervous system. But food alone is not enough to nourish a human being in all their complexity.

This conviction gave rise to PERMANUTRITION — a concept I developed to describe a global, permanent and living approach to nutrition. Permanent, because nutrition is not a diet you follow for six weeks: it is a relationship with the world that you build every day. And living, because it integrates everything that truly nourishes a human being:

• Food — the quality of ingredients, their nutritional density, their origin, their preparation, the pleasure they bring and the awareness with which we choose them.
• Emotions — chronic stress modifies intestinal permeability, microbiome composition, neurotransmitter production. A body under emotional siege cannot optimally assimilate nutrients, even when the plate is perfect.
• Lifestyle — sleep, movement, exposure to natural light, connection to nature. These are not wellness “extras”: they directly condition hormonal, immune and nervous regulation.
• Meaning and connection — relationships with others, with one’s environment, with what gives life meaning. Chronic loneliness generates measurable inflammation. Belonging literally nourishes biology.

PERMANUTRITION refuses fragmentation. It operates from the principle that everything that nourishes matters — and that lasting health is built at the intersection of these dimensions, not by optimizing just one of them.

The Microbiome: The Living Within Us

At the heart of functional health and PERMANUTRITION lies a reality that profoundly changes how we conceive of ourselves: we are not isolated individuals. We are ecosystems. Our body hosts approximately 38 trillion micro-organisms — bacteria, viruses, fungi, archaea — most of which reside in our intestine.

This microbiome is not a simple digestive auxiliary. It is a full organ in its own right, in permanent dialogue with our immune system, our nervous system, our hormonal axis. It participates in synthesizing neurotransmitters (95% of serotonin is produced in the intestine), in regulating inflammation, in modulating our stress response.

But the microbiome is also a mirror. It reflects what we eat, how we live, what environment we inhabit. An impoverished microbiome — in diversity, abundance, balance — testifies to a rupture with the living world: ultra-processed food, excess antibiotics, lack of contact with soil, nature, non-sterile environments.

Caring for one’s microbiome is therefore much more than taking probiotics. It means rediscovering an inner ecology — by feeding diversity, respecting rhythms, reintroducing contact with the living world outside.

ONE HEALTH: One Single Health for All Living Beings

Functional health does not stop at the individual’s skin. It is part of a broader vision, now championed by the WHO, the FAO and many scientists worldwide: the concept of ONE HEALTH.

The principle is as simple as it is radical: human health, animal health and ecosystem health are inseparable. You cannot claim to be healthy in a degraded environment. You cannot hope for nutritious food from exhausted soils. You cannot separate the health of our microbiomes from the health of the microbiomes of soil, oceans, and forests.

In April 2026, France hosted the first international ONE HEALTH Summit — bringing together heads of state, scientists, NGOs and civil society around a common objective: protect the health of the living to better preserve our own. This summit marks a turning point: ONE HEALTH is no longer an academic concept, it is a global political framework for action.

For PERMANUTRITION, ONE HEALTH is not a theoretical abstraction — it is a practical compass. Every food choice is an act of global health: it nourishes or depletes, connects or fragments, respects or destroys the web of life of which we are part.

Feeding the Planet, Feeding Human Beings: One and the Same Question

How do we feed 8 billion human beings without destroying the living systems that make this food possible? This is the central question of the 21st century — and it is profoundly linked to individual health.

Industrial food systems have succeeded in producing sufficient calories to feed the planet. But they have done so at the cost of massive impoverishment: soil impoverishment (loss of 50 to 70% of soil micro-organisms in a century in some regions), nutritional impoverishment of foods (mineral content in vegetables has fallen by 20 to 60% since the 1950s), impoverishment of food biodiversity (75% of agricultural genetic diversity disappeared in the 20th century).

What we do to the planet, we do to our microbiomes. And what we do to our microbiomes, we do to our health. There is no boundary between ecology and nutrition — there is a continuum, a living fabric linking soil to plate, plate to intestine, intestine to brain.

This is why PERMANUTRITION integrates a fundamental ecological dimension:

• Prioritizing living foods: fermented, raw, minimally processed, carrying their own microbiome.
• Reconnecting with seasons: eating what grows in one’s environment, when it grows — an act of biological coherence.
• Supporting production methods that respect the living world: regenerative agriculture, short supply chains, heritage seeds — not only for ideological reasons, but because these foods are biologically richer.
• Reducing ultra-processing: not only because these products are nutritionally depleted, but because their production exhausts planetary resources and destabilizes ecosystems.

Respect for the Living as the Foundation of Health

There is a common thread running through all of functional health, PERMANUTRITION and ONE HEALTH: respect for the living. Not as a philosophical stance, but as a biological requirement.

The living is what self-regulates, self-repairs, adapts. The human being is alive — cells renew themselves, the microbiome adjusts, hormones fluctuate according to precise rhythms. The ecosystem is alive — its cycles, its exchanges, its dynamic balances are of a complexity we are only beginning to understand.

Respecting the living, in practice, means:

• Not seeking to control or suppress the body’s signals, but to listen and understand what they express.
• Working with biology, not against it — supporting natural regulatory processes rather than circumventing them.
• Recognizing that health is not a static state to achieve, but a dynamic balance to maintain — like a garden, not a machine.
• Understanding that the microbiomes of soil, waters, forests and our intestines are part of the same living fabric — and that what we choose to put on our plate participates in this global web.

Functional Health in Practice: Where to Begin?

PERMANUTRITION is not a rigid program. It is an orientation, a compass, a way of asking questions differently. In practice, a functional health consultation always begins with an exploration of the terrain:

• Functional assessment: understanding the systems at play (digestive, hormonal, immune, nervous, mitochondrial), identifying priority imbalances.
• Dietary inquiry: not to count calories, but to understand how current eating nourishes or weakens the terrain.
• Emotional and life inventory: what role do stress, sleep, relationships, and meaning play in the present situation?
• Environment: exposure to endocrine disruptors, quality of water, air, living space — factors that conventional medicine rarely integrates.

From there, we co-build a personalized protocol — which is never the same from one person to another, because the terrain never truly resembles itself.

Conclusion: A New Alliance With the Living

Functional health, PERMANUTRITION, ONE HEALTH — these concepts converge toward the same profound intuition: we are not separate from nature, we are an expression of it. Our biology follows the same laws as the ecosystems that surround us: laws of diversity, interdependence, resilience and dynamic balance.

Lasting health is not an individual performance to optimize. It is the result of coherence — between what we eat and what the planet can offer, between what we feel and what the body expresses, between how we live and how the living world functions.

If you recognize yourself in this vision — if you feel that something in the way you care for yourself, nourish yourself, or understand yourself deserves to be explored differently — I invite you to book an initial consultation — in Liège or online. We always begin by listening. The rest follows.

Further reading: Satiety: physiology, hormones and functional medicine approach · Night sweats: physiological causes · The microbiome: an ecosystem to preserve · Ovulation: a mirror of women’s health · Sleep and nutritional hygiene · What is functional health?

Frequently Asked Questions

What is the difference between functional health and conventional medicine?

Conventional medicine treats diagnosed diseases, often with a symptomatic approach. Functional health seeks the deep causes of imbalances — even before they become defined diseases — and works on the global terrain: diet, microbiome, hormones, nervous system, emotions, environment. The two approaches are complementary, not opposed.

What is PERMANUTRITION?

PERMANUTRITION is a concept developed by Clara Materne to describe a global, permanent and living approach to nutrition. It integrates food (quality, origin, pleasure), emotions (their direct biological impact on the body), lifestyle (sleep, movement, nature) and the ecological dimension (the link between individual health and planetary health). It is not a diet: it is a life orientation.

What is the ONE HEALTH concept?

ONE HEALTH is a framework recognized by the WHO, FAO and many governments, which asserts that human, animal and ecosystem health are inseparable. About 60% of human infectious diseases originate from animals, and the degradation of ecosystems directly impacts our health. ONE HEALTH invites us to conceive and promote health as a common good, shared among all forms of life.

Why is the microbiome so central in functional health?

The intestinal microbiome is the interface between our inner world and the outer world. It influences our immunity (70% of the immune system is located in the intestine), our mood (via the gut-brain axis and serotonin production), our hormonal balance and our inflammatory response. It is also a direct reflection of our diet, environment and emotions. This is why it constitutes a strategic entry point in any functional health approach.

Is functional health only for sick people?

No. Functional health is for anyone who feels their body is not functioning at its full potential — without necessarily having an established diagnosis. Chronic fatigue, sleep disorders, digestive issues, brain fog, hormonal imbalances, diffuse anxiety: signals that conventional medicine sometimes struggles to address, and that functional health can investigate in a precise and personalized way.