Cholesterol Myths Debunked: What the Science Actually Shows
For decades, cholesterol has been misunderstood. Total cholesterol is a poor predictor of heart disease, dietary fat is not the villain, and statins are not the only answer. Here is what the evidence actually says.
Why Cholesterol Advice Needs an Update
The “cholesterol causes heart disease” narrative has been one of the most influential — and most oversimplified — messages in modern medicine. It led to decades of low-fat dietary guidelines, mass statin prescriptions, and a fear of eggs, butter, and red meat that persists today despite mounting evidence to the contrary.
The reality is more nuanced. Cholesterol is essential for life — it forms cell membranes, produces hormones (including testosterone, oestrogen, and cortisol), synthesises vitamin D, and makes bile acids for digestion. The question is not whether cholesterol is “good” or “bad” — it is whether the markers we measure actually predict disease, and whether the dietary advice we follow actually reduces risk.
Steven Hamley, a PhD researcher at Deakin University studying insulin resistance and cardiovascular metabolism, and Dr Glen Davies, a GP and Fellow of the Australasian Society of Lifestyle Medicine, bring both research depth and clinical experience to our approach to heart health and cholesterol management.
5 Cholesterol Myths — Debunked
Myth
“Total cholesterol is a reliable predictor of heart disease”
Reality: Total Cholesterol Is a Poor Predictor
The Framingham Heart Study — the longest-running cardiovascular study in history — found that total cholesterol is a weak predictor of heart disease, particularly in people over 50. Nearly half of heart attacks occur in people with 'normal' cholesterol, and many people with high total cholesterol never develop heart disease.
Why This Matters
Total cholesterol lumps together HDL (protective), LDL (context-dependent), VLDL (harmful), and triglycerides. It is like measuring your bank balance by adding your savings, debts, and pending transactions into one number — the total tells you almost nothing useful. The ratios between these markers are far more informative.
Better Marker
Triglyceride:HDL ratio. A ratio below 1.5 (in mmol/L) is strongly associated with low cardiovascular risk, regardless of total cholesterol. A ratio above 3.0 signals insulin resistance and increased risk. Low carb diets dramatically improve this ratio.
Myth
“LDL cholesterol is 'bad' cholesterol and should always be lowered”
Reality: LDL Particle Size Matters More Than LDL Level
Research published in the Journal of the American Medical Association and the British Medical Journal has shown that LDL-C (the standard test) does not distinguish between large, buoyant LDL particles (Pattern A — generally benign) and small, dense LDL particles (Pattern B — genuinely atherogenic). Two people with identical LDL levels can have vastly different cardiovascular risk profiles.
Why This Matters
Small, dense LDL particles penetrate arterial walls more easily, are more susceptible to oxidation, and are more likely to form plaque. Large, buoyant LDL particles are less harmful. High-carbohydrate diets promote the shift from Pattern A to Pattern B. Low carb diets shift the pattern back — increasing LDL particle size even if total LDL-C rises slightly.
Better Marker
LDL particle number (LDL-P) or apolipoprotein B (apoB) — these measure the actual number of atherogenic particles, not just the cholesterol they carry. Ask your GP for an apoB test if standard LDL concerns you.
Myth
“Saturated fat causes heart disease by raising cholesterol”
Reality: Saturated Fat Is Not the Villain It Was Made Out to Be
A 2020 meta-analysis in the Journal of the American College of Cardiology, reviewing data from 29 studies and over 650,000 participants, concluded: 'The recommendation to limit dietary saturated fat intake has persisted despite mounting evidence to the contrary.' The original Seven Countries Study by Ancel Keys, which launched the low-fat movement, has been widely criticised for cherry-picking data.
Why This Matters
Saturated fat does raise LDL-C in many people, but it primarily raises the large, buoyant (less harmful) LDL particles. It also raises HDL cholesterol — the protective fraction. Meanwhile, replacing saturated fat with refined carbohydrates (as the low-fat era encouraged) increases small dense LDL, raises triglycerides, and worsens insulin resistance — all genuine risk factors.
Better Marker
Focus on the overall metabolic picture: triglycerides, HDL, fasting insulin, waist circumference, and blood pressure. These markers respond dramatically to carbohydrate reduction and are far better predictors of cardiovascular events than dietary saturated fat intake.
Myth
“If your cholesterol is high, you need a statin”
Reality: Statins Are Not the Only Answer — and Not Always the Best One
Statins reduce LDL-C effectively, but their absolute risk reduction for primary prevention (people without existing heart disease) is modest — typically 1–2% over 5 years. A 2022 BMJ review found that the benefits of statins for primary prevention in people over 75 are 'uncertain at best'. Meanwhile, side effects including muscle pain, fatigue, and cognitive issues affect 10–20% of users.
Why This Matters
For people with existing heart disease (secondary prevention), statins have clear benefits. But for otherwise healthy people whose 'high cholesterol' is driven by metabolic syndrome and insulin resistance, addressing the root cause through diet may be more effective — and has no side effects. Many GPs now recognise that lifestyle intervention should be the first-line treatment before medication.
Better Marker
Coronary artery calcium (CAC) score. This imaging test directly measures arterial plaque and is a stronger predictor of heart attack risk than any blood cholesterol number. A CAC score of zero in someone with 'high' LDL is profoundly reassuring — and may mean statins offer no meaningful benefit.
Myth
“Dietary cholesterol (eggs, prawns) raises blood cholesterol dangerously”
Reality: Dietary Cholesterol Has Minimal Impact on Blood Cholesterol
The 2015–2020 US Dietary Guidelines removed the longstanding 300 mg/day cholesterol limit, stating that 'cholesterol is not a nutrient of concern for overconsumption'. A 2018 meta-analysis in Nutrients found that egg consumption (up to 3 per day) does not increase cardiovascular risk in most populations. Your liver produces 80% of your blood cholesterol — dietary intake has a modest and variable effect.
Why This Matters
When you eat more cholesterol, your liver produces less. When you eat less, it produces more. This feedback loop means dietary cholesterol has far less impact on blood levels than was once believed. Eggs are among the most nutrient-dense foods available — rich in choline, B12, selenium, and high-quality protein. Avoiding them based on outdated cholesterol fears deprives you of significant nutritional value.
Better Marker
Instead of avoiding cholesterol-rich foods, focus on reducing refined carbohydrates and seed oils — the dietary factors that genuinely drive metabolic dysfunction and atherogenic lipid profiles.
What Actually Predicts Heart Disease
Forget total cholesterol. These are the markers that cardiologists and metabolic researchers increasingly focus on.
Triglyceride:HDL Ratio
Below 1.5 (mmol/L) is optimal. Above 3.0 signals insulin resistance. Low carb diets improve this dramatically.
Fasting Insulin
The earliest marker of metabolic dysfunction — often elevated years before blood sugar rises. Ideal: below 6 mIU/L.
ApoB / LDL-P
Measures actual atherogenic particle number, not just cholesterol content. More predictive than standard LDL-C.
HbA1c
3-month average blood sugar. Even 'pre-diabetic' levels (5.7–6.4%) indicate metabolic stress that increases cardiovascular risk.
hs-CRP
High-sensitivity C-reactive protein measures systemic inflammation — a direct driver of atherosclerosis independent of cholesterol.
Coronary Artery Calcium (CAC)
Direct imaging of arterial plaque. A score of zero is the strongest evidence against near-term heart attack risk, regardless of LDL level.
Frequently Asked Questions
My GP says my cholesterol is too high. Should I ignore them?
No — never ignore your GP. But you can have an informed conversation. Ask for a full lipid panel including triglycerides and HDL (not just total cholesterol and LDL). Ask about your triglyceride:HDL ratio. If your ratio is good, your HDL is high, and your metabolic markers are healthy, your GP may agree that dietary changes are the best first step before medication.
Will a low carb diet make my cholesterol worse?
Low carb diets typically improve the markers that actually predict heart disease: they lower triglycerides, raise HDL, improve LDL particle size, reduce fasting insulin, and lower blood pressure. Total LDL-C may rise in some people, but this is usually driven by an increase in large, buoyant (less harmful) particles. We monitor your full lipid profile closely.
Should I get an apoB or LDL-P test?
If your standard LDL-C is elevated and you want a clearer picture of your actual cardiovascular risk, an apoB test is the single best blood marker to request. It measures the number of atherogenic particles directly. Most Australian GPs can order it, though it may not be bulk-billed. We can help you interpret the results in the context of your full metabolic profile.
Are eggs really safe to eat every day?
For most people, yes. Multiple large-scale studies have found no increased cardiovascular risk from eating up to 3 eggs per day. Eggs are one of the most nutrient-dense foods available. The exception is people with familial hypercholesterolaemia — a genetic condition affecting about 1 in 250 people — who should discuss egg intake with their specialist.
What is the triglyceride:HDL ratio and how do I calculate it?
Divide your fasting triglyceride level by your HDL level (both in mmol/L). Below 1.0 is excellent, 1.0–1.5 is good, 1.5–3.0 is concerning, and above 3.0 signals significant insulin resistance and cardiovascular risk. This ratio is a far better predictor of heart disease than total cholesterol or LDL-C. Our coaching focuses on optimising it through diet.
Further Reading
Heart Disease & Nutrition
Our comprehensive approach to cardiovascular risk reduction through diet and lifestyle.
Anti-Inflammatory Diet Guide
How reducing inflammation through food choices protects your heart and metabolic health.
High Cholesterol Coaching
Our personalised coaching program for people concerned about their cholesterol numbers.
Keto vs Low Carb
Which dietary approach is right for your metabolic health goals — and how they affect your lipid profile.
Understand Your Real Heart Disease Risk
Book a free 15-minute consultation to discuss your cholesterol results and discover what the numbers actually mean for your cardiovascular health — beyond the oversimplified “good” and “bad” labels.