Normal Cholesterol, Still Heart Disease? What ApoB and Inflammation Reveal
Roughly 75% of people who arrive at the ER with a heart attack have a so-called normal LDL, which suggests the standard cholesterol panel is asking the wrong question. Mark Hyman argues that heart disease is first a metabolic and inflammatory story, driven by insulin resistance and sugar rather than dietary fat. The markers he tracks instead are ApoB, lipoprotein fractionation, Lp(a), hsCRP, fasting insulin and the triglyceride-to-HDL ratio.
Overview
Mark Hyman opens with a number that reframes the whole conversation: in a study of 136,000 people who came to emergency rooms with heart attacks, 75% had a normal LDL level. He describes how his own view changed over decades of practice, from the training that LDL causes heart attacks and saturated fat is the villain, to a far more individual picture. The standard cholesterol test measures the weight of cholesterol, not the number, size and quality of the particles carrying it, and he notes that fewer than 1% of tests ordered look at particle detail.
Since the late 1990s, inflammation research has shown that high cholesterol with low inflammation carries relatively low risk, while inflammation with normal cholesterol still carries elevated risk. He points to metabolic dysfunction - prediabetes, insulin resistance, visceral belly fat - as the engine behind the small dense particles, the oxidised LDL and the arterial damage. Tufts data he cites suggests 93.2% of Americans have some degree of metabolic dysfunction, and 20% of normal-weight people are insulin resistant, a pattern he calls skinny fat.
His practical shift is toward ApoB, lipoprotein fractionation, Lp(a), hsCRP, fasting insulin, the triglyceride-to-HDL ratio and a calcium score for imaging. The lifestyle side is equally direct: cut refined starch and sugar, eat whole anti-inflammatory foods, build muscle, sleep, manage stress. He closes on agency - knowing your numbers means the trajectory is something you can influence, not something you inherit passively.
Key quotes
5If cholesterol were truly the main cause of heart disease, then why do half the people who have heart attacks have normal LDL levels?
It's sugar, not fat, that's causing you to die of heart attacks.
ApoB is not part of a regular cholesterol panel, but it is the most reliable marker of your risk of heart attacks.
This is angry fat, and it's inflamed fat, and it's spewing out tons of inflammation.
You're not really at the mercy of your genetics or your numbers.
Key ideas
9Normal LDL is not a clean bill of health
In a study of 136,000 heart attack patients, about 75% had a normal LDL reading. The number most people are shown does not, on its own, describe cardiovascular risk.
The standard panel measures weight, not particles
A conventional test tells you the mass of cholesterol, not how many particles carry it or how large they are. An LDL of 130 could be a hundred large particles or a thousand small dense ones.
Inflammation reframed the picture
Research from the late 1990s onward showed that high cholesterol with low inflammation carries modest risk, while high inflammation raises risk even when cholesterol looks normal. hsCRP became a central marker.
Metabolic dysfunction is the upstream driver
Insulin resistance from a high starch and sugar diet, low activity and belly fat produces atherogenic dyslipidemia - the small dense particles that damage arterial lining. Cholesterol is described as a bystander in that process.
ApoB as the surrogate for metabolic health
ApoB counts the damaging particles in one number and rises with insulin resistance, prediabetes and visceral fat. Cardiology guidelines in 2023-2024 recognised it as causal rather than merely associated.
Lp(a) is the genetic wildcard
About one in five people carry an elevated lipoprotein(a). It is largely inherited and hard to move directly, which makes tight control of every other risk factor more important for those who have it.
Saturated fat is not the primary driver
Large meta-analyses, the PURE study and Framingham data found no clear correlation between dietary saturated fat and heart disease, while trans fat raised risk. Individual responses to fat still vary widely.
Skinny fat is a real pattern
Normal body weight and normal BMI can coexist with poor body composition and visceral fat. Roughly 20% of normal-weight people are insulin resistant and carry risk comparable to obesity.
Imaging answers what blood cannot
Cholesterol is a surrogate marker, not a diagnosis. A calcium score shows whether plaque actually exists, and Hyman notes patients with alarming lipid panels and completely clean arteries.
Practical takeaways
7- 1
Ask for the markers that carry information 8:40
The panel Hyman tracks: ApoB, lipoprotein fractionation, Lp(a), hsCRP and fasting insulin, alongside the standard lipids. Fasting insulin, he notes, appears on well under 1% of ordered panels.
- 2
Calculate your triglyceride to HDL ratio 12:10
A ratio near 1 is the target. Triglycerides under 100 and HDL above 50-60 are the reference points he uses; a ratio of 4-5 signals insulin resistance even with a normal LDL.
- 3
Use the tape measure and the mirror 19:00
Waist circumference at the widest part of the belly is a free proxy for visceral fat. No tape measure needed for the rough version - jump in front of a mirror and watch what moves.
- 4
Try a continuous glucose monitor briefly 20:00
Even a short period wearing one reveals how specific foods move your blood sugar. That personal response data is more useful than a single static fasting reading.
- 5
Cut the shared root of both problems 21:20
Refined starch and sugar drive inflammation and insulin resistance simultaneously. Replace them with whole foods, colourful vegetables, omega-3 fats and no ultra-processed products.
- 6
Build muscle, then keep moving 22:00
Strength training improves insulin sensitivity and helps lower ApoB by making muscle a better sink for glucose. Cardio, sleep, stress regulation and daily steps complete the set.
- 7
Track trends, not single snapshots 21:00
One test is a data point; a line over years is a signal. Retesting on a regular rhythm shows whether the changes you made actually moved your numbers.
Topics & chapters
15The question that started the rethink
Half of heart attack patients have normal LDL. Hyman opens by admitting he changed his mind about cholesterol.
What he was trained to believe
LDL causes heart attacks, lower it at all costs, avoid saturated fat. A simple message that clinical practice complicated.
Why the standard test falls short
Conventional panels weigh cholesterol rather than counting particles. Under 1% of tests examine particle size and number.
The inflammation model arrives
Seminal work on inflammation showed hsCRP may predict risk better than LDL. Cholesterol becomes dangerous when it oxidises.
Metabolic dysfunction and atherogenic dyslipidemia
Insulin resistance produces small dense particles that damage arteries. Aside from a small genetic subset, this is the main engine.
Sugar, not fat
The headline claim, tied to the books Eat Fat Get Thin and The Blood Sugar Solution.
ApoB, the most reliable marker
A single number reflecting all the damaging particles, recognised as causal in the 2023-2024 cardiology guidelines.
Lp(a), the inherited risk
One in five people carry an elevation. Hard to change directly, so everything else must be managed tightly.
93% and the triglyceride to HDL ratio
Tufts data on metabolic dysfunction, plus the simple ratio that exposes insulin resistance behind a normal LDL.
Where the inflammation comes from
Toxins, microbiome, stress and infection all contribute, but sugar and refined flour dominate. Visceral fat as an inflammatory organ.
The panel he actually runs
ApoB, lipoprotein fractionation, Lp(a), hsCRP, fasting insulin, insulin resistance score, triglyceride to HDL ratio.
Skinny fat and continuous glucose monitoring
Normal weight with poor body composition carries real risk. A CGM shows how your own body responds to specific foods.
Testing, imaging and tracking trends
Test, don't guess. A calcium score shows whether plaque exists, and repeated testing turns numbers into a trajectory.
Food, movement and supplement principles
Cut sugar and starch, build muscle, sleep, manage stress. Omega-3, a multivitamin, CoQ10, magnesium, fibre and plant sterols as general principles, not prescriptions.
You are not at the mercy of your numbers
Understanding your own biology gives you leverage over heart health today.