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BOOK 2 OF THE VAT-TRAP SERIES
Track Your Heart
Health
Knowledge without measurement is just opinion. The practical home toolkit — and how to run an N-of-1 trial on yourself.
From the Naked Heart series — making something complicated simple, but no simpler than the truth allows.
~80 PAGES 1-2 HOUR READ COMING 2026
WHAT THIS BOOK IS
The practical companion to the framework.
Book 1 lays out the theory: four modifiable pillars of cardiometabolic risk, and why the fourth — visceral fat — was missing from medicine's standard toolkit for most of the last fifty years. Book 2 hands you the equipment.
It's the practical companion: how to measure each of the four pillars at home, between clinic visits, using tools that together cost less than a single private specialist appointment. A tape measure for the waist. A blood pressure monitor for the cuff readings. A continuous glucose monitor for the metabolic response. A simple sit-to-stand test for strength.
You will also learn the discipline of an N-of-1 trial: change one variable at a time, hold the others constant, measure the result, iterate. Discover your own glucotype. Read your Current Glucose Profile. Build a personal data trail your GP will thank you for. The reason for this discipline is not curiosity — it is the principle that runs through every book in this series: what can you do forever. Small, repeatable changes are the only changes worth measuring, because they are the only ones that hold.
Skimmable, manual-style, designed to be opened and used rather than read cover-to-cover.
THE PREMISE
The things your blood tests cannot see
You walk into your GP's surgery for a routine check
The numbers say you're fine.
And yet — your waistband has tightened. Your sleep is patchier. The energy of your forties has quietly drained away. You are doing everything you were told to do.
The numbers are missing something. They have been missing it for decades, and the cost — in heart attacks, strokes, type 2 diabetes, dementia, and several common cancers — has been catastrophic.
WHY NOW?
A trap designed for almost everyone
Why now? Why us? Why this generation?
The modern food environment has been engineered for profit, not for human metabolism. Ultra-processed foods — products formulated in laboratories rather than kitchens — now make up more than half of the calories eaten in the UK and the US. Their architecture is precise: cheap macronutrients (refined starch, industrial seed oils, added sugars) combined to hit what the food industry calls the bliss point — the formulation that makes you eat more without feeling full.
For a substantial proportion of the world's population, this is a metabolic mismatch their genes and gut biome were never designed for. People of South Asian, East Asian, Hispanic and African descent show the steepest rise in visceral fat and the earliest onset of insulin resistance — often at lower body weights than their European counterparts.
And in much of the world, the older industrial assault on metabolic health is still uncontrolled. Tobacco remains widely advertised, cheaply available, and regulated only patchily — particularly across South Asia, the Middle East, parts of Africa, and Eastern Europe. Smoking is not a separate problem from the four pillars. It is the fire underneath all four.
FASHION TITLE
By the time the
bathroom scales
notice, the trap has
been closing for twenty
years.
THE FRAMEWORK
The four pillars of modern
cardiometabolic risk
Modern preventive cardiology rests on four measurements. Each matters. Each can be measured. None of them, on their own, is enough.
PILLAR I
Blood Pressure
The single most modifiable cardiovascular risk factor — and the most poorly measured.
PILLAR II
Apo B/LDL-C
An elevated lipoprotein cholesterol particle count and concentration causes coronary atherosclerosis
PILLAR III
Glucose & Insulin
Carbohydrate sensitivity and insulin resistance happens decades before diabetes appears on a blood test.
PILLAR IV
Visceral Fat (VAT)
The missing fourth pillar — and the master driver of the other three.
"What about exercise, diet, sleep, stress?" The four pillars are not the only things that matter — they are the things that can be measured. Sedentary lifestyle, poor diet quality, insufficient strength training and poor sleep all accelerate the trap; resistance training, dietary change, and good sleep all reverse it. The four pillars give you the dashboard. The lifestyle changes are how you move the needle.
For visceral fat specifically, the most practical home measurement is the waist-to-height ratio — a tape measure and a calculator, repeatable every month, useful anywhere in the world. The threshold to remember is 0.5. CT-based imaging exists as the research-grade reference standard, but for the great majority of people the tape measure carries the framework.
WHAT'S INSIDE
The book is built around three central ideas
Three lenses on the same problem — how the trap forms, what we measure, and how we measure it.
I
II
III
The Trap
How visceral fat accumulates over decades through a slow, almost invisible shift in how the body stores and burns energy. By the time the trap has closed, it has usually been closing for twenty years.
The Pillars
The four measurements that, taken together, reveal what is actually happening in your metabolism. Three of them are familiar. The fourth is the one that was missing.
The Tools
CT imaging with AI analysis, continuous glucose monitoring, ApoB and Lp(a) testing. None of these are yet routinely available on the NHS. Modern preventive cardiology has, at last, the diagnostic toolkit it spent fifty years waiting for.
WHY NOW
From Cardiology 1.0 to Cardiology 3.0
For most of the twentieth century, cardiology was a discipline of reaction. The discipline I trained and practised in for thirty years got better at managing the consequences of heart disease — but still arrived too late.
Cardiology 1.0
SYMPTOM ERA
The single most modifiable cardiovascular risk factor — and the most poorly measured.
Cardiology 2.0
INTERVENTION ERA
Got better at stenting blocked arteries. Saved lives — but still arrived too late.
Cardiology 3.0
INTERVENTION ERA
Sees risk early enough to do something about it — using imaging, AI, metabolic measurement, and an honest understanding of what actually drives disease.
Book 1 is the introduction to that shift, written for the person who suspects their healthcare has been measuring the wrong things, and who wants to understand what the right things are before deciding what to do about them.
A NOTE ON NOISE
Expert advice in a noisy room
The internet has democratised health information. It has also drowned it. On any given day you can find people insisting statins are essential, others insisting they are poison, and a third group selling supplements that will solve everything. Most people have no idea who to trust — and the loudest voices are rarely the most informed.
I cannot make the noise go away. What I can do is offer the considered view of a consultant cardiologist with thirty years of clinical practice, written for the reader rather than the journal, and stripped of every piece of jargon that does not earn its place.
The Naked Heart principle: make
something complicated simple, but no simpler than the truth allows.
Most of your cardiovascular risk — and most of your brain-health risk too — comes from the four pillars in the framework above. Look after these four, and you will look after your heart and your brain. The book series tells you how.
WHO IS THIS FOR
Honest about who this is — and isn't — for
THIS BOOK IS FOR
Anyone over 35 who has wondered why their weight does not match their effort
Anyone whose blood tests look "fine" but who does not feel fine
Clinicians — GPs, nurses, dietitians — who want a working framework
for the patient who "shouldn't" have had a heart attack but did
Patients of mine, between consultations
Anyone with a family history that suggests early action would be wise
THIS BOOK IS NOT
A diet book
A fitness manual
A list of supplements
A long read — most readers finish it in under two hours
A substitute for medical advice
The diagnostic foundation that comes before diet, fitness,
or medication — and the book most readers will start with.
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