How to use: Narrate the history and mechanisms of immunology as if you're three drinks in and desperately trying to explain cPNI to a confused friend at a pub. You're enthusiastic, slightly rambling, going off on tangents, but the SCIENCE IS CORRECT. The comedic framing forces you to simplify without losing accuracy — and the tangents are where the cross-system connections live.
Why it's out there: The "drunk" delivery pattern — enthusiasm, tangents, over-explanation, circling back — mirrors how the brain ACTUALLY retrieves connected information. When you allow yourself to ramble between concepts, you're practising the associative network retrieval that the exam tests. Also: it's hilarious, and you'll actually listen to it again.
Important: You don't need to actually drink. The slurring is optional. The science is not.
(Record in enthusiastic, slightly rambling pub-explanation style)
"OK, OK, OK so listen. LISTEN. I'm going to explain the immune system to you and it's going to blow your mind because everything — EVERYTHING — you think you know about it is wrong. Well, not wrong. Incomplete. Very, very incomplete.
So like, people think the immune system is about fighting germs, right? White blood cells eat bacteria, done, sorted. That's like saying a car is about wheels. Sure, technically, but you're missing the ENGINE.
Right so there's TWO immune systems. No wait, there's ONE immune system with two BRANCHES. Innate and adaptive. Innate is the bouncer at the door — big, fast, not very specific. It recognises PATTERNS. Like, it doesn't know 'oh that's E. coli strain K-12,' it knows 'that's a gram-negative bacterium because I can see LPS on its surface.' Pattern recognition receptors. Toll-like receptors. TLRs. There are like TEN of them and they each recognise different stuff. TLR-4 is the big one — that's the LPS detector.
And then adaptive immunity is like... the detective agency. Slower. Takes days. But INCREDIBLY specific. T-cells and B-cells. Each one has a unique receptor made by — get this — RANDOMLY REARRANGING gene segments. V, D, and J segments shuffled like a deck of cards. It's called VDJ recombination and it generates like 10 to the power of 11 possible receptors. That's more combinations than there are stars in the galaxy. From random shuffling. In your BONE MARROW.
But here's where it gets NUTS — and this is the bit nobody tells you — the immune system doesn't just fight. It RESOLVES. And the resolution part? That's actually MORE important than the fighting part. Because —
Oh wait, I need to tell you about inflammation first. Sorry, let me back up.
So when TLR-4 sees LPS, it activates this whole cascade — MyD88, IRAK, TRAF6, and then NF-kappa-B gets freed from its inhibitor and goes to the nucleus and turns on EVERYTHING. TNF-alpha, IL-1-beta, IL-6, COX-2, the whole pro-inflammatory programme. This is GOOD. This is NORMAL. This is your body going 'threat detected, mobilise resources, fight fight fight.'
And then neutrophils come in — they're like the infantry, right? First soldiers on the scene. They follow a chemical gradient — IL-8, also called CXCL8 — and they just BLAST everything with reactive oxygen species and enzymes and it's brutal but effective.
BUT. BUT BUT BUT.
This was supposed to last like three days. MAX. Three days of acute inflammation and then — and THIS is the bit that changed everything for me — the SAME arachidonic acid that was making pro-inflammatory prostaglandins through COX-2... the SAME fatty acid... starts getting processed by DIFFERENT enzymes. 15-lipoxygenase. And instead of prostaglandins, you get LIPOXINS.
It's called the eicosanoid class switch and honestly it's the most beautiful thing in biology. Same substrate. Different enzyme. Opposite outcome. Like... like the same flour can make bread or cake depending on what you do with it. Bad analogy. Whatever.
And lipoxins tell the neutrophils to STOP COMING. And then resolvins — from omega-3, from fish oil, from DHA and EPA — they come in and they flip the macrophages from M1 — that's the angry killing mode — to M2 — that's the cleaning and healing mode. And the M2 macrophages EAT the dead neutrophils. Efferocytosis. EATING. THE. DEAD. CELLS. So they don't rupture and spill their guts and cause MORE damage.
And if ALL of this works? If the trigger is removed, the SPMs are produced, the macrophages switch, the clean-up happens? Then inflammation RESOLVES. Completely. Back to baseline. Tissue repaired. Done.
And if it DOESN'T work — if any of those steps fail — you get... lowers voice ...low-grade chronic inflammation. The thing that causes EVERYTHING. Heart disease. Diabetes. Depression. Alzheimer's. Autoimmunity. Cancer. All of it. All of it traces back to inflammation that started but never finished.
Wait, let me tell you about something called the selfish immune system..."
"Right so I was in Module 6 — Organs, digestive system, Itziar Hernandez teaching — and she drops this fact that just... it just broke me.
70% of your immune system is in your gut. SEVENTY PERCENT. Your gut. The tube you put food in. The thing you never think about unless it hurts. It contains the majority of your immune cells, has its own nervous system with 500 MILLION neurons — that's more than your spinal cord — and produces 90% of your body's serotonin.
And I'm sitting there like... why did no one LEAD with this? Why is gastroenterology not the first thing they teach in medical school? The gut is running the show!
OK so, the barrier. ONE cell layer. One. Between the lumen — where all the bacteria and food and potential antigens are — and the lamina propria — where your immune system lives. One cell layer held together by tight junction proteins. Claudins. Occludin. ZO-1. And there's this molecule called ZONULIN that controls how tight the junctions are.
And gliadin — which is a peptide from gluten digestion — triggers zonulin release. Opens the gates. Not just in coeliac people. In EVERYONE. Different degrees, sure, but the mechanism is universal. Alessio Fasano's research. Groundbreaking stuff.
So now you've got an open gate and on the other side you've got — among other things — LPS. Lipopolysaccharide from gram-negative bacteria. And it crosses. Into the bloodstream. And your macrophages in the lamina propria go BALLISTIC because they've got TLR-4 and TLR-4 HATES LPS and now NF-kappa-B is activated and you're inflamed. From your GUT.
This is called metabolic endotoxemia. And here's the kicker — you can MEASURE it. Zonulin levels. LPS-binding protein. hs-CRP. But most doctors DON'T. Because they weren't taught to look at the gut when someone comes in with depression or fatigue or joint pain.
But in cPNI we do. Because we know that the gut, the brain, and the immune system are having a three-way conversation ALL THE TIME through the vagus nerve — 80% of which is AFFERENT, meaning gut-to-brain, not brain-to-gut — and through cytokines, and through microbial metabolites like butyrate and propionate, and through tryptophan metabolism...
Oh GOD, the tryptophan thing. Let me tell you about the kynurenine pathway. So tryptophan is the precursor to serotonin, right? But when the immune system is activated, it induces this enzyme called IDO — indoleamine 2,3-dioxygenase — and IDO STEALS tryptophan away from serotonin synthesis and shunts it into the kynurenine pathway. And downstream of kynurenine you get quinolinic acid which is an NMDA receptor agonist — excitotoxic, neurotoxic — and you get less serotonin AND more neurotoxicity AT THE SAME TIME.
So: leaky gut → LPS → inflammation → IDO activation → tryptophan diversion → low serotonin + high quinolinic acid → depression.
GUT. TO. BRAIN. Through the immune system.
That's PNI. That's psychoneuroimmunology. The gut causes depression through immune-mediated tryptophan diversion. And the doctor prescribes an SSRI — a drug that recycles serotonin in the synapse — but if the serotonin was never MADE because the tryptophan was stolen upstream... the SSRI doesn't work. Treatment-resistant depression. Which should be called 'we're treating the wrong thing' depression.
...I need another drink. Of water. Obviously."
"OK so Leo Pruimboom. Leo. The man. He comes in Module 2 and he just... he flips the table on everything.
His argument — and this is the foundation of cPNI — is that modern disease is not a malfunction. It's a MISMATCH. Your genome — your DNA — was shaped over two million years of evolution in conditions that no longer exist. And your body is still running the old software.
Let me give you examples because they're beautiful.
Obesity. Your fat storage system — adipose tissue, insulin, leptin — evolved in a world where famine was regular. Your body is BRILLIANT at storing fat because the ones who couldn't store fat DIED during the lean months. So you have this incredibly efficient fat storage system... in a world where the famine never comes. The system works PERFECTLY. The ENVIRONMENT is wrong.
Type 2 diabetes. Your insulin resistance mechanism evolved as an immune strategy — during acute infection, the immune system INDUCES insulin resistance to redirect glucose from muscle to immune cells. Because immune cells need glucose for the Warburg effect — anaerobic glycolysis, fast ATP production. This is CLEVER. This is ADAPTIVE. But now the immune system is chronically activated — from gut permeability, from processed food, from stress — so insulin resistance becomes PERMANENT. A temporary immune trick became a metabolic disease.
Depression. Your sickness behaviour programme — fatigue, social withdrawal, anhedonia, loss of appetite — evolved to make you STAY IN BED when you're fighting an infection. Conserve energy. Avoid spreading disease. Don't eat so AMPK activates and immune function improves. ADAPTIVE. BRILLIANT. But now this programme is being triggered by chronic low-grade inflammation, not by actual infection. You feel depressed not because your brain is broken but because your immune system is whispering 'you're sick, rest' 24 hours a day.
And the intermittent living thing — oh this is so good — so Pruimboom's argument is that the body needs OSCILLATION. Not constant comfort. Stress followed by recovery. Cold followed by warmth. Fasting followed by feeding. Movement followed by rest. Acute inflammation followed by complete resolution.
Every system in the body is designed for RHYTHMIC challenge. Exercise creates a cortisol pulse — which is healthy. Chronic stress creates a cortisol plateau — which is destructive. Same hormone! Fasting activates AMPK and autophagy — cellular cleaning. Constant feeding keeps mTOR dominant — no cleaning ever. Exercise mobilises NK cells and creates immune oscillation. Sedentary life lets the immune system stagnate.
The prescription isn't medicine. The prescription is: live more like a caveman. Move daily. Fast regularly. Sleep with the sun. Eat real food. Get cold sometimes. Connect with your tribe.
Not because it's trendy. Because it's what your genome EXPECTS. And the gap between what your genome expects and what you give it... that gap is disease.
...I love this stuff. Can you tell? Am I being too much? I'm being too much. ONE more story and then I'll stop..."
"Right, so everyone — EVERYONE — thinks cortisol is the bad guy. 'Oh, cortisol is the stress hormone, cortisol makes you fat, cortisol is killing you.' No. NO. Cortisol is one of the most important molecules in your body and we have SLANDERED it. Let me set the record straight.
Cortisol is a glucocorticoid. Steroid hormone. Made in the zona fasciculata of the adrenal cortex from cholesterol. And yes, I said cholesterol. Another molecule we've slandered, by the way, but that's a different episode.
The HPA axis — hypothalamic-pituitary-adrenal axis — this is the command chain. Your hypothalamus detects stress — and stress means ANYTHING that disrupts homeostasis, so it could be a lion, could be an email, could be low blood sugar, could be inflammation — and it releases CRH. Corticotropin-releasing hormone. CRH travels through the hypophyseal portal system — this tiny private blood vessel network between the hypothalamus and the anterior pituitary — and tells the corticotrophs to release ACTH. Adrenocorticotropic hormone.
ACTH goes systemic. Hits the adrenals. Binds MC2 receptors on the zona fasciculata. And cortisol is released.
Now HERE is where it gets interesting and HERE is where everyone gets it wrong.
Cortisol in an ACUTE pulse is FANTASTIC. Like, genuinely life-saving and performance-enhancing. It mobilises glucose from liver glycogen — glycogenolysis AND gluconeogenesis. It mobilises fatty acids from adipose tissue — lipolysis. It suppresses non-essential functions: digestion slows down, reproductive hormones drop, the immune system gets a brief 'stand down' signal. All resources go to dealing with the stressor. This is ADAPTIVE. This is what kept your ancestors alive when the lion appeared.
And then — this is the crucial bit — cortisol hits its OWN off-switch. Negative feedback. Cortisol binds glucocorticoid receptors in the HIPPOCAMPUS and the HYPOTHALAMUS. The hippocampus says 'cortisol is high enough, tell the hypothalamus to stop releasing CRH.' CRH drops. ACTH drops. Cortisol drops. System resets. Beautiful. Elegant. Self-regulating.
That's the PULSE. Stress → response → recovery → baseline. Like a wave. Up, down, up, down.
NOW. What happens when the stress NEVER STOPS? When it's not a lion that leaves after 10 minutes but a mortgage, a divorce, a toxic job, a 24-hour news cycle, chronic gut inflammation sending LPS across the barrier every single day?
Cortisol stays elevated. Not dramatically — not Cushing's syndrome levels — just... elevated. Persistently. The rhythm flattens. Normally you get a cortisol awakening response — a big spike in the first 30-45 minutes after waking, maybe 50-75% increase — and then a gradual decline through the day, reaching its lowest point around midnight when melatonin takes over. That's the RHYTHM. That rhythm is health.
Chronic stress flattens the rhythm. Morning peak blunts. Evening cortisol stays too high. The oscillation disappears. And THAT'S when cortisol becomes the villain everyone thinks it is.
Because now the hippocampus — which is supposed to be the off-switch — is bathing in cortisol 24/7. And hippocampal neurons are SENSITIVE to glucocorticoids. Chronic cortisol causes dendritic retraction in CA1 and CA3 regions. The hippocampus SHRINKS. MRI studies show this in chronic stress, in PTSD, in major depression. Your MEMORY ORGAN is being pruned by the very hormone that's supposed to have a feedback loop THROUGH it.
And it gets worse. Because when the hippocampus shrinks, its ability to detect cortisol and signal 'enough' to the hypothalamus WEAKENS. So the feedback loop breaks. CRH keeps being released. ACTH keeps flowing. Cortisol keeps coming. But now the system can't turn itself off. The thermostat is broken.
And the immune system? Oh the immune system has HAD it. It's been getting cortisol's 'stand down' signal for months. So it does what any employee does when the boss keeps crying wolf — it STOPS LISTENING. The immune cells downregulate their glucocorticoid receptors. This is glucocorticoid resistance. Cortisol is still high in the blood but it can't SUPPRESS anything anymore.
So now you've got: high cortisol that can't regulate immunity, a shrinking hippocampus that can't regulate cortisol, and an immune system running unchecked producing low-grade inflammation that nobody can stop.
The conspiracy isn't that cortisol is evil. The conspiracy is that we built a civilisation that converted a beautiful pulsatile survival mechanism into a flatlined metabolic poison. Cortisol didn't change. WE changed its context.
You know what fixes it? Morning sunlight — resets the cortisol awakening response via the SCN. Exercise — creates an acute cortisol pulse followed by genuine recovery. Breathwork — activates the vagus, shifts toward parasympathetic, lets cortisol clear. Social connection — oxytocin modulates the HPA axis, dampens CRH release. Sleep — nighttime cortisol nadir is when growth hormone peaks and tissue repair happens.
Not drugs. Not supplements. RHYTHM. Give cortisol its rhythm back and it stops being the villain. It was never the villain. It was a hostage.
...sorry, I'm getting emotional about a steroid hormone. Where was I?"
"OK so this one — this is the one that made me change my entire diet. Not because of some wellness influencer. Because of the BIOCHEMISTRY. Because once you understand what omega-3 fatty acids actually DO at the molecular level, not eating fish becomes as stupid as not putting oil in your car engine.
So there are two omega-3s that matter: EPA — eicosapentaenoic acid — and DHA — docosahexaenoic acid. You get them from oily fish, algae, or supplementation. Your body can technically convert ALA from flaxseed into EPA and DHA but the conversion rate is like 5-10%. Maybe. It's pathetic. You need the real thing.
Now, why do they matter? Three reasons, each one bigger than the last.
REASON ONE: membrane composition. Every cell in your body is wrapped in a phospholipid bilayer. The fatty acids in that bilayer determine how FLUID the membrane is. More omega-3 = more fluid. More omega-6 and saturated fat = more rigid. Membrane fluidity affects EVERYTHING — how well receptors work, how signals get transduced, how ion channels open and close. Your brain is 60% fat by dry weight and DHA is the dominant omega-3 in neural membranes. Low DHA = stiffer neuronal membranes = impaired neurotransmission. That's not a theory, that's physics.
And here's a sneaky one: in the inner mitochondrial membrane, there's a phospholipid called cardiolipin that's essential for holding the electron transport chain complexes in their proper configuration. Cardiolipin incorporates DHA. Low DHA = disrupted cardiolipin = less efficient oxidative phosphorylation = less ATP = fatigue. Your mitochondria literally run better on omega-3.
REASON TWO: the substrate for resolution. And this is the BIG one. This is the one from Module 5 that changes everything.
So you know how inflammation starts — TLR activation, NF-kappa-B, cytokines, neutrophil recruitment, the whole war. And you know it's supposed to RESOLVE. The eicosanoid class switch, lipoxins from arachidonic acid, great, I covered that in episode 1.
But lipoxins are only PART of the resolution toolkit. The other part — arguably the MORE important part — comes from omega-3. Specifically:
Resolvins. EPA gets converted into E-series resolvins (Resolvin E1, E2). DHA gets converted into D-series resolvins (Resolvin D1, D2, D3, D4, D5). These molecules actively PROMOTE resolution. They stop neutrophil infiltration. They enhance macrophage efferocytosis — that's the eating-of-dead-neutrophils thing. They switch macrophages from M1 to M2. They promote tissue repair.
Protectins. DHA → Protectin D1. Also called Neuroprotectin D1 in the brain. Anti-apoptotic. Neuroprotective. Shields neurons from inflammatory damage. If you have chronic neuroinflammation — which you DO if you have low-grade systemic inflammation because it crosses the blood-brain barrier via circumventricular organs and active transport — you NEED protectin D1 to protect your neurons. And you can't make it without DHA.
Maresins. Macrophage mediators in resolving inflammation. Also from DHA. Produced by macrophages themselves during efferocytosis. They amplify the resolution response and promote tissue regeneration. The macrophage eats the dead neutrophil, produces maresins, and the maresins tell the tissue 'we're healing now.'
These are collectively called specialised pro-resolving mediators — SPMs. And they are the most important discovery in immunology in the last 20 years and NOBODY outside of research knows about them. Charles Serhan at Harvard figured this out. Pruimboom teaches it in Module 5. And it explains EVERYTHING about chronic disease.
Because here's the punchline: the modern Western diet has an omega-6 to omega-3 ratio of about 20-25:1. Our ancestors? 1-3:1. Omega-6 fatty acids — from seed oils, processed food, grain-fed meat — are the PRECURSOR to pro-inflammatory eicosanoids. Arachidonic acid, the mother of prostaglandins and thromboxanes. More omega-6 = more inflammatory substrate.
And simultaneously, less omega-3 = less RESOLUTION substrate. You've tipped the balance in BOTH directions. More fuel for the fire, AND removed the fire extinguisher.
REASON THREE: direct immune modulation. Omega-3s aren't just SPM precursors. EPA and DHA directly modulate immune cell function. They get incorporated into the membranes of macrophages, T-cells, dendritic cells, and they change how those cells signal. They reduce NF-kappa-B activation. They promote Treg differentiation — regulatory T-cells, the immune peacekeepers. They modulate the NLRP3 inflammasome.
And there's a receptor — GPR120, also called FFAR4 — a G-protein coupled receptor on macrophages and adipocytes that directly SENSES omega-3 fatty acids and triggers anti-inflammatory signalling cascades. Your immune cells have a RECEPTOR specifically for omega-3 that says 'resolution mode, please.' You just have to give them the ligand.
So when I say fish oil changed my life molecularly, I mean: I went from a body that couldn't resolve inflammation to one that could. I gave my macrophages the substrate to make resolvins. I gave my neurons DHA for protectins. I gave my mitochondrial membranes the building blocks for functional cardiolipin. I shifted my omega-6:3 ratio from 'chronic disease factory' to 'functional mammal.'
Two grams of EPA+DHA per day. That's all. Two grams. The difference between a body stuck in inflammation and one that can heal itself.
...I should get sponsorship from a fish oil brand. I should NOT get sponsorship from a fish oil brand. Forget I said that. The point stands on its own."
"OK I need to be careful with this one because I'm not anti-doctor. Doctors save lives. Doctors are brilliant. But the SYSTEM they work in — conventional medicine — has a blind spot you could drive a bus through. And cPNI sees what's in that blind spot.
So your standard GP appointment. You go in. You say 'I'm tired all the time, I ache, I can't concentrate, I feel low.' The doctor orders blood work. Standard panel. Full blood count, liver function, kidney function, thyroid, maybe HbA1c.
Results come back. Everything is 'within normal range.' Doctor says: 'Good news, your blood work is fine. Maybe try getting more sleep.'
And you leave feeling CRAZY. Because you're not fine. You know you're not fine. Your body is screaming at you. But the numbers say you're fine.
HERE is the problem. 'Normal range' is a statistical concept, not a biological one. The reference range is typically the central 95% of a supposedly healthy population. But that population includes people with subclinical inflammation, people with insulin resistance they don't know about, people with suboptimal vitamin D. The 'normal' range is the range of NORMAL MODERN HUMANS, not the range of OPTIMAL BIOLOGICAL FUNCTION.
Let me give you specific examples because this makes me crazy.
hs-CRP. High-sensitivity C-reactive protein. The gold standard marker for systemic inflammation. A normal GP blood panel often doesn't include it. When it does, the 'normal' range is usually under 5 mg/L, sometimes under 10. TEN. At 10 mg/L of CRP you are SIGNIFICANTLY inflamed. The cPNI optimal is under 0.5. Under ZERO POINT FIVE. Between 0.5 and 3 is the grey zone — low-grade chronic inflammation. The thing that drives every chronic disease. And the lab says 'normal' up to 5 or 10.
A patient walks in with CRP of 2.8. The lab report says 'normal.' The doctor says 'fine.' But 2.8 means their liver is producing C-reactive protein in response to IL-6 signalling, which means macrophages are activated SOMEWHERE, which means there's an inflammatory process running that hasn't resolved. Where? Gut? Adipose tissue? Periodontal disease? Somewhere. But nobody's looking because 2.8 is 'within range.'
Fasting glucose. Normal range: 3.9 to 5.5 mmol/L, roughly. But a fasting glucose of 5.4 in a 35-year-old isn't 'normal' — it's pre-diabetic TRAJECTORY. By the time glucose hits 7 and you get a diabetes diagnosis, the insulin resistance has been building for maybe 10-15 YEARS. The horse has left the barn, crossed two counties, and started a new life. You needed to catch it at 5.0 when the insulin was already creeping up.
Which brings me to fasting INSULIN. Most GPs don't test it. They test glucose. But glucose is the LAST thing to go wrong. Insulin rises YEARS before glucose does, because the pancreas compensates by pumping out more insulin to force glucose into resistant cells. The HOMA-IR calculation — fasting glucose times fasting insulin divided by 22.5 — tells you about insulin resistance LONG before glucose goes out of range. But it's not on the standard panel.
Vitamin D. Lab reference range usually says 'normal' above 50 nmol/L. Some say 30. THIRTY. At 30 nmol/L your immune system is running on fumes. Vitamin D isn't just about bones — it's a secosteroid hormone that modulates T-cell differentiation, promotes Tregs, supports barrier integrity, modulates the balance between Th1 and Th2 responses. The cPNI target is 100-150 nmol/L. The gap between 'normal' and 'optimal' for vitamin D is ENORMOUS and has real immunological consequences.
Ferritin. 'Normal' range for women is sometimes listed as 12-150 ng/mL. TWELVE. At 12 your iron stores are essentially empty. Your mitochondria need iron for the electron transport chain — Complex I and Complex III have iron-sulphur clusters. No iron, no electron transport, no ATP, hello fatigue. But the lab says 12 is 'normal.'
And THEN there's the stuff that's never tested at all. Zonulin for gut permeability. Omega-3 index. LPS-binding protein. Cortisol rhythm — not just a single morning cortisol, but the DIURNAL PATTERN via salivary cortisol at four time points. Comprehensive stool analysis for microbiome composition and short-chain fatty acids. None of this is standard.
Now here's where the five metamodels come in — this is Module 8, Itziar Hernandez, diagnosis. In cPNI, you don't just run blood work and check boxes. You look at the patient through five LENSES:
The evolutionary metamodel: what mismatches exist between this patient's lifestyle and their genome? Are they sedentary? Do they eat processed food? Are they sleep-deprived? Chronically stressed?
The biochemical/metabolic metamodel: what do the functional lab markers show? Not just 'within range' but 'optimal for biological function'? What pathways are disrupted?
The psycho-neuro-endocrine metamodel: what's happening in their life? Their relationships? Their cortisol rhythm? Their sense of meaning and social connection? The CTRA — conserved transcriptional response to adversity — shows that loneliness CHANGES GENE EXPRESSION. Upregulates NF-kB. Downregulates antiviral genes. Your social life is an immune modulator.
The immunological metamodel: where is the inflammation? Is it resolving? What's driving it? Barrier dysfunction? Adipose tissue? Chronic infection? And where's the resolution pathway? Are SPMs being produced?
The clinical/therapeutic metamodel: given all of the above, what's the integrated treatment plan? Not one drug for one symptom — a multi-system intervention that addresses root causes across all metamodels.
FIVE lenses. One patient. And the answer is NEVER 'your blood work is normal.' The answer is 'let's look deeper.'
This is why cPNI practitioners catch things that conventional medicine misses. Not because they're smarter. Because they're looking at different things. With different reference ranges. Through different metamodels. Asking different questions.
Your doctor isn't wrong. The SYSTEM is incomplete. And the patients who fall through the gaps — the ones told 'it's all in your head' or 'everything looks fine' — those are cPNI's patients. Those are the ones we're trained to help.
...right, I need to stop ranting about reference ranges. Let's get another round."
"So this one's personal. Because I guarantee — I GUARANTEE — you're doing the thing I'm about to describe. And you don't realise how much damage it's causing. Because it's invisible. It happens every night. And it's this: you look at your phone before bed.
'So what?' you say. 'Everyone does.' Yeah. Everyone does. And everyone has disrupted circadian rhythms, poor sleep, and a compromised immune system. Coincidence? Let me explain why it's NOT.
It starts with LIGHT. Specifically, the wavelength. Blue light — around 460 to 480 nanometres — is the precise frequency that a set of specialised cells in your retina are most sensitive to. These aren't rods or cones. These are intrinsically photosensitive retinal ganglion cells — ipRGCs — and they contain a photopigment called melanopsin.
Melanopsin doesn't help you SEE. It tells your brain what TIME it is. These ipRGCs project directly to the suprachiasmatic nucleus — the SCN — which is the master circadian clock in the hypothalamus. The SCN runs a roughly 24-hour cycle and it uses light input to SYNCHRONISE that cycle to the actual solar day. This is called photoentrainment.
When the SCN detects light through melanopsin, it says 'it's daytime.' When light disappears, it says 'it's nighttime' and it signals the pineal gland to begin converting serotonin into melatonin. N-acetylserotonin as the intermediate, melatonin as the product. This takes about 2 hours after light cessation. That's why melatonin onset is typically around 9pm if you're following natural light cycles.
But HERE'S the thing. Your phone screen emits PEAK light at exactly the melanopsin-sensitive range. 460-480nm. You're essentially pointing an artificial sun directly at the cells that tell your brain what time it is. And your brain says: 'Oh! It's daytime! Do NOT release melatonin.'
So melatonin doesn't come. Or it comes late. Or it comes at reduced amplitude. And you might think 'well, I still fall asleep eventually, so what's the big deal?'
The big deal is that melatonin isn't just a sleep molecule. Melatonin is a POWERHOUSE and we have criminally underestimated it.
First: antioxidant. Melatonin is a direct free radical scavenger. It neutralises hydroxyl radicals, peroxyl radicals, and peroxynitrite. It's MORE potent as an antioxidant than glutathione in some contexts. And unlike most antioxidants that get used up, melatonin's metabolites — cyclic 3-hydroxymelatonin, AFMK — are ALSO antioxidants. It's an antioxidant cascade. One melatonin molecule can neutralise up to 10 reactive oxygen species through its metabolite chain.
Every night your body is supposed to get a massive antioxidant flush. From melatonin. And you're blocking it by staring at Instagram until midnight.
Second: immune modulation. Melatonin receptors — MT1 and MT2 — are found on T-cells, B-cells, monocytes, NK cells. Melatonin enhances NK cell activity during sleep. It modulates cytokine production — increases IL-2 and interferon-gamma from Th1 cells during the night, which is why your adaptive immune system does its best work while you sleep. It promotes T-cell trafficking to lymph nodes during sleep — naive T-cells and central memory T-cells leave the bloodstream and concentrate in lymph nodes where they're more likely to encounter antigens presented by dendritic cells. This is ADAPTIVE IMMUNE LEARNING and it happens at night.
Studies show shift workers have higher rates of cancer. Higher rates of metabolic syndrome. Higher rates of cardiovascular disease. Higher rates of depression. And the leading hypothesis is melatonin disruption. Not just 'bad sleep' — the loss of melatonin's direct biological functions.
Third: circadian gating of immunity. Your immune system has its own clock. Literally. Immune cells have clock genes — BMAL1, CLOCK, PER, CRY — and their function oscillates over 24 hours. TLR expression varies by time of day. NF-kB activity has circadian variation. Cortisol suppresses immunity during the day (when you're active and exposed to threats, prioritising acute responses), and melatonin permits immune activation at night (when you're resting and can afford the energy cost of immune surveillance).
Disrupt the melatonin signal and you disrupt this ENTIRE oscillation. The immune system loses its rhythm. It doesn't know when to activate and when to rest. Low-grade inflammation increases because the nocturnal anti-inflammatory counter-regulation never happens properly.
Fourth — and this is the one that gets me — autophagy. Melatonin promotes autophagy. AMPK activation increases at night. mTOR decreases. The cells clean house during sleep. Damaged mitochondria are tagged for mitophagy. Misfolded proteins are cleared. This maintenance programme runs on a circadian schedule and melatonin is one of the key signals that says 'it's maintenance time.'
No melatonin → reduced autophagy → accumulation of cellular damage → accelerated ageing → increased cancer risk → neurodegeneration.
From. Your. Phone.
Oh and I almost forgot — the cortisol connection. Cortisol and melatonin are RECIPROCAL. When melatonin rises, cortisol falls. When cortisol rises in the morning, melatonin falls. They're a seesaw. If you suppress melatonin with evening light exposure, cortisol stays elevated longer. Elevated evening cortisol disrupts sleep architecture — less slow-wave sleep, less REM, less hippocampal memory consolidation.
So the intervention — and I love how simple this is — the intervention is: STOP LOOKING AT SCREENS TWO HOURS BEFORE BED. Or at minimum, use blue light blocking glasses (the real ones, not fashion ones — they need to block 460-480nm). Get morning sunlight exposure to ANCHOR the cortisol awakening response. Sleep in a dark room. Like a CAVE.
This is basic circadian hygiene. This is what every human body received for two million years of evolution and we threw it away in one generation because of Netflix.
Pruimboom talks about this. Light as a drug. Light as an immune modulator. Light as the most fundamental environmental signal your biology relies on. And we're overdosing on it at the wrong time.
The night the melatonin didn't come... was last night. And the night before. And every night you scrolled your phone in bed.
...I need to put my own phone down after saying all that. Bit hypocritical otherwise."
"OK last one, and this one — THIS one — genuinely changed how I think about exercise forever. Because I used to think exercise was about fitness. Cardiovascular health. Looking good. Burning calories. And sure, it's all those things. But that's like saying the ocean is 'wet.' Technically true. Missing the ENTIRE point.
Muscle is an ENDOCRINE ORGAN. Your skeletal muscle — which is the largest organ in your body by mass, like 40% of your body weight — secretes signalling molecules when it contracts. These molecules are called myokines. And they do things that will blow your mind.
The star of the show is IL-6. Yes. THAT IL-6. The same IL-6 that's a pro-inflammatory cytokine when released from immune cells and adipose tissue. The same IL-6 that I ranted about in episode 1.
But when IL-6 is released from contracting muscle, it's a COMPLETELY DIFFERENT story. Muscle-derived IL-6 signals through the classical pathway — binding the membrane-bound IL-6 receptor — and in this context it's ANTI-inflammatory. It stimulates the production of anti-inflammatory cytokines IL-10 and IL-1 receptor antagonist (IL-1ra). It SUPPRESSES TNF-alpha production.
Let that sink in. The same cytokine. From a different tissue. Through a different receptor pathway. Has the OPPOSITE effect.
During exercise, IL-6 from muscle can rise 100-FOLD. Hundred times its resting level. And this massive pulse of muscle IL-6 creates a systemic anti-inflammatory wash. After exercise, IL-10 is elevated. TNF-alpha is suppressed. The immune system gets a recalibration signal.
This is COMPLETELY different from adipose tissue IL-6, which is released continuously at low levels, signals through trans-signalling (soluble IL-6 receptor + gp130), and drives chronic inflammation. Same molecule. Context is everything.
But IL-6 isn't the only myokine. Not even close.
There's irisin. Discovered in 2012. Released from muscle during exercise via cleavage of the membrane protein FNDC5. Irisin does something extraordinary: it converts white adipose tissue into BEIGE adipose tissue. White fat stores energy. Beige fat BURNS energy through UCP1-mediated thermogenesis, like brown fat. So exercise literally changes the CHARACTER of your fat tissue. Your muscle tells your fat to stop being a passive storage depot and start being a metabolically active furnace. Through a myokine. Through contraction.
There's BDNF — brain-derived neurotrophic factor. Yes, the brain produces it. But muscle contraction also drives BDNF elevation, and BDNF crosses the blood-brain barrier. It promotes neurogenesis in the hippocampus — the growth of NEW NEURONS. In the MEMORY CENTRE. From EXERCISE. This is why exercise improves learning and memory. This is why Tom Fox in Module 10 says movement is non-negotiable. Your muscles are sending growth signals to your BRAIN.
There's myonectin — promotes fatty acid uptake. Meteorin-like — drives alternative macrophage activation (M2, the repair phenotype). Musclin — enhances exercise endurance and mitochondrial biogenesis. There are over 600 identified myokines and we've probably only characterised a fraction of their functions.
Now here's the evolutionary angle — and this ties into the mismatch stuff from episode 3.
For two million years, muscle contraction was CONSTANT. Walking, running, climbing, carrying, building, hunting, gathering. The myokine signalling was continuous. Your immune system EXPECTED these signals. Your fat tissue expected the irisin. Your brain expected the BDNF. Your metabolism expected the AMPK activation that comes with energy depletion during movement.
Exercise isn't a bonus. It's not a luxury. It's not 'going to the gym.' Exercise is the BASELINE signalling environment your entire physiology was designed for. Not exercising is like removing a vital organ. Your muscles are supposed to be talking to every other system, all day, every day. And when they go silent — when you sit for 10 hours — every system that depends on those signals starts to malfunction.
This is why sedentary behaviour is independently associated with mortality REGARDLESS of whether you exercise. You can go to the gym for an hour and then sit for 12 hours and the 12 hours of sitting STILL causes damage. Because it's not about the exercise session. It's about the continuous myokine signalling that your body expects from regular movement throughout the day.
Tom Fox — Module 10, Nutrition and Movement — he hammers this. He says movement is medicine. But it's not medicine in the pharmaceutical sense — take this dose at this time. It's medicine in the BIOLOGICAL sense — this is a fundamental input that your physiology requires to function. Like oxygen. Like water. Like sunlight.
And the metabolic angle — oh let me just do this one because it ties everything together.
When you exercise, ATP drops in muscle cells. AMP rises. The ratio shifts. And AMPK — AMP-activated protein kinase, the cellular energy sensor — ACTIVATES. AMPK does three massive things:
One: it increases glucose uptake in muscle INDEPENDENT of insulin. GLUT4 transporters go to the surface without needing the insulin → IRS-1 → PI3K → Akt pathway at all. This is why exercise helps insulin resistance even when the insulin signalling pathway is broken by TNF-alpha. There's a BACK DOOR for glucose entry. And exercise opens it.
Two: it activates fatty acid oxidation. Beta-oxidation ramps up. You burn fat. Not because of 'calories out' — because AMPK flips the metabolic switch from storage mode to burning mode.
Three: it triggers AUTOPHAGY. The cellular cleaning programme. Damaged mitochondria, misfolded proteins, accumulated junk — tagged and recycled. Exercise is a cleaning service for your cells. And remember: AMPK and mTOR are opponents. Exercise activates AMPK, which suppresses mTOR, which permits autophagy. Constant feeding activates mTOR, which suppresses AMPK, which blocks autophagy. You need BOTH — building AND cleaning — in oscillation. Intermittent living.
And then post-exercise, when you eat and rest, mTOR comes back online. Muscle protein synthesis. Adaptation. Growth. The system oscillates. Stress, recovery, stress, recovery. Exactly as designed.
So muscle is an immune organ (myokines modulate inflammation), an endocrine organ (IL-6, irisin, BDNF), a metabolic organ (AMPK, glucose disposal, fat oxidation), and a neurological organ (BDNF, neuroplasticity). It's arguably the most important organ you have for preventing chronic disease. And we treat it like it's for vanity.
Pruimboom would say: your muscles aren't just for moving. They're for COMMUNICATING. Every contraction is a signal. Every signal tells your body: 'I am alive. I am active. I am doing what my genome expects.' And when that signal stops... the body assumes the worst.
...right. I'm done. Eight episodes. I think I need to lie down. Which is ironic given that last rant.
Actually no. I'm going for a walk. For the myokines."
| Episode | Title | Key Concepts | Module |
|---|---|---|---|
| 1 | "How Your Immune System Actually Works" | Innate/adaptive, TLRs, NF-kB, eicosanoid class switch, SPMs, resolution failure | 4, 5, 7 |
| 2 | "The Time I Found Out the Gut Runs Everything" | GALT, tight junctions, zonulin, LPS, vagus nerve, kynurenine pathway, IDO | 6, 3, 7 |
| 3 | "How a Caveman's Body Explains Everything Wrong With You" | Evolutionary mismatch, intermittent living, sickness behaviour, oscillation | 2, 7, 10 |
| 4 | "The Cortisol Conspiracy" | HPA axis, CRH→ACTH→cortisol, negative feedback, glucocorticoid resistance, hippocampal atrophy | 3, 7 |
| 5 | "Fish Oil Changed My Life (Molecularly)" | EPA/DHA, resolvins/protectins/maresins, membrane fluidity, cardiolipin, GPR120, omega-6:3 ratio | 5, 10 |
| 6 | "Why Your Doctor Is Looking at the Wrong Things" | hs-CRP, optimal vs normal ranges, fasting insulin, HOMA-IR, five metamodels, functional testing | 8 |
| 7 | "The Night the Melatonin Didn't Come" | Melanopsin, SCN, melatonin as antioxidant/immune modulator, clock genes, autophagy, cortisol reciprocity | 3, 2 |
| 8 | "Muscles Are an Immune Organ and Nobody Told Me" | Myokines, muscle IL-6 (classical), irisin, BDNF, AMPK vs mTOR, GLUT4, autophagy, metabolic flexibility | 10, 7 |
| Episode | Title | Focus |
|---|---|---|
| 9 | "The Autoimmune Friendly Fire Incident" | Molecular mimicry, Th17/Treg balance, bystander activation, loss of tolerance |
| 10 | "Your Fat Is Talking Behind Your Back" | Adipokines, leptin resistance, adipose tissue as immune organ, visceral vs subcutaneous |
| 11 | "The Microbiome Is a Civilisation, Not a Side Character" | Enterotypes, butyrate, Akkermansia, SCFA signalling, dysbiosis, antibiotics |
| 12 | "How to Actually Read a Blood Test" | Practical lab interpretation using cPNI optimal ranges |