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Heart & cholesterol guide · Chapter 1 of 19

Important context before you start

Cardiovascular health is a lifelong project — and the tests that actually predict your risk are different from the ones a standard checkup runs. This is chapter one; the other eight are listed at the foot of the page.

1

Important context before you start

Cardiovascular health is a lifelong project — and the tests that actually predict your risk are different from the ones your standard checkup might run.

Read this first

What you eat is the foundation. Everything else on this page is an amplifier.

The single biggest lever over your lipids, glucose, blood pressure and long-term cardiovascular risk is what goes on your plate every day — not which supplements you take. The supplement tiers below are genuinely useful, but they work on top of a good diet; they cannot rescue a poor one. If you only change one thing, change how you eat.

And here is the uncomfortable part: most people who are confident they "eat pretty healthily" are partly wrong — usually about refined carbohydrates. Bread, rice, pasta, breakfast cereal, potatoes and "healthy" snacks behave like sugar in the bloodstream, and the effect is almost invisible without measuring it. Two tools cut through the guesswork: the sugar-equivalents comparison in Section 11 (which shows how ordinary starchy meals stack up against a can of cola) and a short CGM trial (Section 9) that reveals your personal glucose response to the foods you actually eat.

01 · The lever

Diet does the heavy lifting

Real food, low refined-carb load, oily fish, legumes, vegetables, olive oil. Get this right and the numbers move.

02 · The amplifiers

Supplements are helpers

They fine-tune a good diet — omega-3, a sensible multi, magnesium. They never substitute for it.

03 · The intensity bonus

Move — and push the pace

A gentle stroll helps; brief bursts of genuinely vigorous effort help far more, minute for minute (Section 12).

04 · The progress signal

Track your waist, not the scale

A tape measure around your middle predicts cardiac risk better than weight — and shows progress when the scale doesn't (Section 12).

🍽️ Want the whole approach in one place? The Eating for a Healthy Heart guide turns this into a balanced-plate and portion guide, a 12-day meal plan, gluten-free options and easy swaps — plain-English and printable.

Heart health begins early — and matters for everyone

Cardiovascular disease is the world's leading cause of death, but the damage doesn't start in middle age — it starts in childhood. Autopsy studies of teenagers and young adults consistently show early fatty streaks and even raised plaques in coronary arteries, even in people who appear completely healthy. Childhood diet, body composition, glucose handling, and sleep patterns lay the metabolic and vascular foundation for the next 60-80 years.

Visible signs of poor diet are not a reliable indicator of cardiovascular trajectory. A slim child eating ultra-processed food, sugary drinks, and refined carbohydrates is depositing the same atherogenic particles into their arterial walls as an overweight adult. Conversely, an overweight child eating a Mediterranean-style diet may have far healthier vasculature than appearances suggest. This guide is intended for adults, but the principles — minimise refined carbohydrate and sugar load, prioritise oily fish and legumes, move daily, sleep well, manage stress — apply at every age.

A word on medication before you read on. In busy real-world practice, statins are often started almost as a matter of course — off a QRISK score and a single standard lipid panel — without first running a genuinely monitored trial of diet and exercise, or the fuller blood work that would show how much risk is really there. Done properly, that means a defined period of supported lifestyle change (refined-carb load, oily fish, daily movement, sleep) with before-and-after blood tests to see how your numbers actually respond, ideally alongside the better risk markers (apoB, Lp(a), hs-CRP, HbA1c — see below) and a coronary-calcium (CAC) scan in borderline cases, plus ruling out treatable causes such as an underactive thyroid. A plan merely mentioned in a ten-minute appointment is not the same as one that is prescribed, supported and measured.

Crucially, this is about borderline, primary-prevention cases — not a reason to refuse or stop a statin. For anyone at genuinely high risk — established cardiovascular disease, a previous heart attack or stroke, familial hypercholesterolaemia, diabetes, or a very high apoB/LDL or Lp(a) — statins are strongly evidence-based and should not be delayed for a lifestyle experiment; the genetic (Mendelian-randomisation) evidence that lowering apoB lowers events is settled. Lifestyle and medication are also not either/or — diet and exercise are the foundation regardless, and you should never start, stop or change a prescribed medicine without discussing it with your GP. The point is simply that the decision should rest on complete information and a fair trial of the basics, rather than being made on autopilot.

For GPs and clinicians reading this: the framework below outlines a structured approach to cardiovascular risk assessment that goes beyond the standard NHS lipid panel. It is designed to identify both the drivers of atherosclerosis (atherogenic particle burden) and the environment that allows those particles to lodge in arterial walls (inflammation, glycation, methylation). Both must be addressed for meaningful risk reduction.

Recommended cardiac assessments

  • ECG / Exercise ECGBaseline electrical rhythm; exertional changes (Private:£150-500)
  • EchocardiogramStructural assessment of chambers, valves, function (Private:£375)
  • Carotid (neck) ultrasoundDirect visualisation of plaque in major arteries (Private:£95)
  • CT coronary angiogramLow-radiation direct imaging of coronary arteries (Private:£700-1500)
  • Cardiac MRI (T1/T2 mapping)Only if echocardiogram suggests something unclear — detects subclinical inflammation or fibrosis (Private:£800)
The mechanism that matters most

Why insulin — not cholesterol alone — decides whether plaque forms

Atherosclerosis needs two things, not one: a seed and a soil. The seed is the atherogenic particle — apoB-carrying LDL and remnants — and it is genuinely necessary: you cannot build arterial plaque without it. But whether those particles actually burrow into the artery wall, oxidise and grow into plaque is decided by the soil — the condition of the wall itself. And the single biggest thing degrading that soil in a modern diet is chronically high insulin, driven by repeated blood-sugar spikes from refined carbohydrate and sugar. This is why someone can have a "normal" cholesterol panel and still be quietly laying down plaque — and why the panel alone is such an incomplete picture of risk.

01 · The seed

Insulin corrupts the particles

Chronically high insulin tells the liver to overproduce triglycerides and VLDL — lowering HDL and shifting your LDL towards small, dense particles. Small dense LDL slips through the wall more easily, is retained longer, and oxidises faster than large, buoyant LDL. Two people with the same "LDL cholesterol" can carry very different real risk because of this — which is why apoB (particle count) beats LDL-C.

02 · The soil

Sugar spikes glycate the wall

Every glucose spike glycates proteins — both the LDL particle (making it stickier and longer-lived) and the delicate endothelial lining and its protective glycocalyx, the barrier that normally keeps particles out. Your HbA1c is a three-month average of exactly this damage. A glycated, leaky wall is precisely the surface where apoB particles get trapped.

03 · The accelerant

It switches off the wall's defences

Insulin resistance and repeated glucose excursions impair the artery's nitric-oxide "non-stick" coating and switch on adhesion molecules that recruit inflammatory cells into the wall. Inflammation — your hs-CRP — is the accelerant that turns a trapped particle into a growing plaque.

04 · The blind spot

It runs silent for years

The body holds fasting glucose normal by pumping out ever more insulin — so insulin can run high for a decade or more while fasting glucose, and often LDL, still look "fine". The damage accumulates invisibly. Triglycerides and remnant cholesterol on your panel are the earliest fingerprints of this — long before glucose rises.

The model: keep the seed low (apoB) and keep the soil healthy (low insulin and glucose load). For most people in the modern world the under-recognised, highly modifiable lever is the second one — and it starts on your plate. The sugar-equivalents table (Section 11) shows how ordinary "savoury, sensible" carbs spike blood sugar like a can of cola, and a short CGM trial (Section 9) reveals exactly which of your foods are driving the spikes.
To be fair and accurate: this is not the claim that "cholesterol doesn't matter". Lifelong apoB/LDL exposure is causal for atherosclerosis — the genetic (Mendelian-randomisation) evidence on that is settled, and people with naturally low LDL are strongly protected. The point is narrower and more useful: the number on a standard cholesterol panel is incomplete. Particle quality, glycation and inflammation — all downstream of insulin — determine how dangerous that cholesterol actually is, and they are largely invisible until you look for them.
🩸

Essential blood tests for cardiovascular risk

Two tiers of testing that map directly to the two mechanisms of atherosclerosis: direct drivers (the particles that cause plaque) and critical environment (the inflammation and metabolic damage that allows those particles to lodge in arterial walls). Both must be addressed.

1

The Non-Negotiable Core

Direct drivers of atherosclerosis
  • Full lipid panelNHS Baseline Total cholesterol, LDL, HDL, and triglycerides — the standard NHS starting point and what most GPs already order. Triglycerides within this panel are the most actionable marker — they are the premier indicator of dietary response, reacting rapidly to carbohydrate load, insulin resistance, and overall metabolic state. However, the panel alone is no longer sufficient for accurate cardiovascular risk assessment; it must be supplemented with ApoB and Lp(a) below.
  • ApoB (Apolipoprotein B)Essential · Private The gold standard, period. Measures the exact number of atherogenic (plaque-causing) particles in your blood — a vastly superior metric to standard LDL-C, which only measures the weight of cholesterol inside those particles. NHS GPs cannot easily order this — typically requires private testing in the UK via onedaytests.com, Medichecks, Thriva, or similar UK private labs. Worth the £20-40 cost — it changes the conversation about your cardiovascular risk.
  • ApoA-1 + ApoB:ApoA-1 ratioRecommended · Private Apolipoprotein A-1 is the main protein of HDL particles — measuring it gives a more accurate picture of "good cholesterol" capacity than HDL-C alone. The ApoB:ApoA-1 ratio is arguably the single most predictive lipid risk metric available — established in the AMORIS and INTERHEART studies as a better predictor of cardiovascular events than LDL or the cholesterol ratio. Target ratio: men <0.7, women <0.6. Usually included with ApoB testing on private panels — make sure both are requested together.
  • Lp(a) (Lipoprotein(a))Once A highly thrombogenic, genetically determined particle that standard lipid panels completely miss. Because it is genetically driven, you only need to test this once in your life. Sometimes available via NHS with a family history of premature cardiovascular disease, but commonly needs private testing alongside ApoB.
  • APOE genotypeOnce · Optional A single gene with three alleles (ε2, ε3, ε4) that profoundly influences lipid response. ε4 carriers respond more to dietary saturated fat (LDL rises more) but also benefit more from Mediterranean intervention. ε2 carriers tend to higher TG and benefit from carbohydrate restriction. Not standard NHS testing — typically accessed via consumer genetic services (23andMe, Nebula Genomics, Living DNA). Once-in-a-lifetime test, and genuinely useful for personalising the dietary approach — but optional rather than essential.
💡 UK testing routes: Standard lipid panel via your GP. ApoB, ApoA-1, and Lp(a) via private labs — most cost-effectively bundled in the onedaytests.com Ultimate Heart Health Blood Test (£89) which covers Tier 1 + most of Tier 2 in one panel or get the onedaytests.com Ultimate Longevity Health Blood Test (£325) which covers everything. Alternatives: individual tests at onedaytests.com, Medichecks, Thriva, or Forth — finger-prick or venous draw, results in days, £20-50 per single test. APOE genotype: consumer genetic kits like 23andMe (Limited DNA £159), Nebula Genomics (Entire DNA £205 Recommended), or Living DNA (£159).
2

The Critical Environment

Metabolism & inflammation
  • hs-CRPEssential The ultimate marker for systemic inflammation. You can have an aggressively low ApoB, but if hs-CRP is elevated, your residual risk for a cardiovascular event remains high.
  • HbA1cEssential A three-month average of blood glucose. High blood sugar glycates (damages) the endothelial lining of blood vessels — creating the precise damage that ApoB particles get stuck in.
  • HomocysteineRecommended An inflammatory amino acid that actively scars arterial walls. Managing this metabolic exhaust pathway requires sufficient methylation to recycle homocysteine back into methionine — exactly where TMG does its heavy lifting.
  • Liver panel (ALT + GGT + ALP)Essential The liver is the engine of lipid metabolism — it dictates how cholesterol is produced and cleared. GGT in particular is emerging as an independent risk factor for cardiovascular disease and oxidative stress.
  • TSH (Thyroid Stimulating Hormone)Essential Thyroid hormones directly control LDL receptor expression on the liver. Hypothyroidism reduces these receptors, causing LDL to back up in the bloodstream — making it one of the most common secondary causes of hyperlipidaemia. UK and international lipid guidelines strongly recommend checking TSH before initiating statin therapy: fixing the thyroid often resolves the cholesterol issue without medication, and statins given in undiagnosed hypothyroidism significantly increase the risk of myopathy.
  • Potassium + Sodium (U&E panel)Essential High cholesterol and high blood pressure travel together — both share the same atherogenic mechanism (endothelial damage + LDL infiltration), and treating one without the other leaves cardiovascular risk substantially elevated. Potassium is a core regulator of blood pressure; it directly counterbalances the BP-raising effect of sodium and is routinely measured alongside it as part of the standard U&E (urea & electrolytes) panel that every UK GP can request for free. Both low potassium (<3.5 mmol/L — common with thiazide diuretics, chronic vomiting/diarrhoea, eating disorders) and high potassium (>5.3 mmol/L — common with ACE inhibitors, ARBs, spironolactone, kidney impairment) carry independent cardiovascular and arrhythmia risk. Recent cohort data shows mortality rises even within the "high-normal" 4.6-5.0 mmol/L band in hospitalised patients. If you're being treated for hypertension, potassium should be checked at least annually; it's a single tube of blood that costs the NHS pennies.

Choose what to read next

18 more chapters · about 4.1 hours in total

If you read three

  1. This page — why a normal panel can mislead you
  2. The diet chapter — the single biggest lever you have
  3. Your numbers — read against the range they should sit in

Otherwise the numbering is a reading order, not a requirement. Every chapter defines its own terms, so you can start wherever your question is.

Understand the problem

What is actually going wrong in an artery, and which widely-repeated claims are wrong.

4 chapters

Measure where you stand

The tests worth asking for, what the numbers mean, and how to see plaque directly.

10 chapters
02 Before you act on the number Why the same person tested twice gets two different answers, how much change is needed before it is real, and why the LDL-C on most UK reports was calculated rather than measured. Placed before the calculator deliberately. 1,993 words · about 9 min 03 Your numbers, interpreted Interactive Enter your panel and see each marker read against its reference interval, with a three-tier supplement strategy, dose adjustments, a statin-alternative pathway and projected 12-week outcomes. 7,230 words · about 33 min 04 Continuous glucose monitoring The 14-day protocol, device comparison, target ranges, and how to read what you see. The most underused diagnostic tool in primary care. 3,685 words · about 17 min 05 Fatty liver — MASLD and fibrosis A third of adults have it and most will never come to harm. Telling those apart takes blood tests you have probably already had — and the commonest cause of death in fatty liver disease is cardiovascular, not hepatic. 1,545 words · about 7 min 06 CAC scoring — imaging plaque directly The Agatston score and its four tiers, why the score is not a treatment target, and what to do when it comes back above zero. 3,543 words · about 16 min 07 Blood pressure — the other number The second axis of cardiovascular risk, and the one where measurement error is largest. What the UK thresholds actually are, why home readings beat clinic ones, and what moves the number. 4,791 words · about 22 min 08 Ezetimibe, and how low to go The drug written off in 2008 on an imaging test and rehabilitated by genetics and hard outcomes — why it is the first thing to add to a statin, what the trials actually showed, and why the primary prevention trial will never be done. 3,566 words · about 16 min 09 PCSK9 inhibitors, in full Four different medicines under one name, and the two things most often got wrong: inclisiran can be started in primary care, and its threshold is 2.6 where the antibodies need 3.5 to 4.0. With the eligibility table, the safety questions, and what is proven. 2,139 words · about 10 min 10 Prediabetes, and the programme nobody offers you HbA1c 42-47 is the most actionable result on a routine blood test and the one most often filed as "we will keep an eye on it". What the band means, the free national programme you have to ask for, and why four in five referrals do not finish it. 1,505 words · about 7 min 19 Advanced genetics & diagnostics APOE status, familial hypercholesterolaemia, Lp(a) as a genetic risk, and the advanced tests worth considering when the standard picture does not add up. 4,409 words · about 20 min

Change something

The interventions that move the numbers, in rough order of how much they move them.

3 chapters

Day to day

Sleep and alcohol — the levers that do not fit into a clinic visit.

2 chapters