High LDL, Clean Arteries: The Study That Challenges the Dogma

High LDL, Clean Arteries: The Study That Challenges the Dogma

by Laurent Glatz – for Athletic Carnivore

You've been told that high LDL clogs your arteries. Period.

Then a hundred cardiac scans complicated the story.

For decades, LDL has been labeled the number one enemy. The higher it rises, the greater the cardiovascular risk. This equation is taught, repeated, and ingrained. It shapes clinical practice, justifies millions of prescriptions, and reassures by its simplicity.

And then biologically troubling profiles emerge.

Men and women who are lean, insulin-sensitive, with low triglycerides, high HDL, following a ketogenic or strict carnivore diet. Their metabolism is stable. Their blood sugar is low. Their measured systemic inflammation is minimal. Yet their LDL skyrockets. 250, 300, sometimes 400 mg/dL.

According to the dominant model, these individuals should rapidly accumulate atherosclerotic plaque. The story seems prewritten.

One Hundred Scans to Test the Dominant Model

This is precisely what the study led by Dave Feldman and Dr. Nick Norwitz aimed to test. One hundred participants. Two coronary scans each, performed one year apart. Two hundred images of coronary arteries. A direct measurement of plaque, not a blood estimate.

First observation: the initial plaque level is the best predictor of subsequent progression. Nothing extraordinary. The biology is consistent.

Second, more explosive finding: despite LDL levels among the highest ever observed in a prospective study, no statistically significant association was found between LDL or ApoB and plaque progression in this metabolically healthy cohort.

The particle presumed to be causally central does not predict the measured evolution.

At this point, scientific tension is palpable. Either the model is incomplete, or the methodology is flawed.

When Imaging Changes Risk Interpretation

The scans were then analyzed by several imaging platforms, including artificial intelligence systems specialized in volumetric quantification of coronary plaque. Three independent analyses converged: overall low progression, presence of regressions in some participants, expected variability around measurement noise in subjects with little initial plaque.

But one analysis diverged sharply: more marked progression, no cases of regression. Zero.

And one technical detail changed everything.

This analysis was not fully blinded. Metadata potentially allowed identification of scan order, baseline and follow-up. In longitudinal imaging, blinding is a fundamental methodological requirement to avoid interpretation bias.

A reanalysis via other platforms, this time strictly blinded, did not reproduce the same conclusions. Results aligned with the initial convergent analyses.

Then an even more troubling element emerged. Some participants submitted their own scans—the exact same images—to the initial platform for an independent reread via their cardiologists. Results sometimes differed massively. Progressions became regressions. A median increase of about twenty cubic millimeters dropped nearly to zero. In one case, significant progression became a clear plaque reduction.

Reproducibility wavers. And with it, confidence in the initial interpretation.

LDL Does Not Act in Isolation

The heart of the debate now goes beyond LDL alone. It touches on the deep biological mechanisms of atherosclerosis.

LDL carries cholesterol. It can penetrate the vascular endothelium, oxidize, be internalized by macrophages, form foam cells, and initiate plaque. Yes. This process is documented. But it does not act in a vacuum.

The endothelium must be dysfunctional. Inflammation must be present. The oxidative environment must be favorable. Chronic high insulin, repeated hyperglycemia, glycemic stress, protein glycation, renin-angiotensin system activation, redox imbalance—all modulate arterial susceptibility.

A particle can be necessary but not sufficient.

In this specific cohort, the metabolic terrain is radically different from the classic high-risk profile. Low insulin. Low triglycerides. High HDL. Stable blood sugar. Reduced inflammation. The context changes the dynamics.

This does not mean LDL is unimportant. It means its effect may strongly depend on the biological environment in which it circulates.

What the Study Does Not Yet Prove

The controversy is intense. Some see a methodological flaw. Others, a crack in the paradigm. The authors themselves acknowledge limitations. One year is short. Five-year data will be crucial. LDL might show a later correlation. Nothing is definitively settled.

But one certainty emerges.

The simplistic model “high LDL equals rapid progression” does not automatically apply in a context of optimal metabolic health.

Science advances when data challenge certainties. It regresses when it protects dogmas.

The Real Scientific Question

The question is no longer whether LDL is “good” or “bad.” The question is more demanding. More subtle. More uncomfortable.

In a metabolically healthy organism, is isolated high LDL truly an autonomous driver of atherosclerosis, or merely one variable among many in a far more complex cascade?

The answer will not fit into a slogan or an automatic prescription. It will require time, data, and above all intellectual courage.

The question remains: who is ready to face these data without looking away?

What Recent Data Force Us to Distinguish

The KETO-CTA data published and extended in longitudinal analyses do not prove LDL is unimportant. They show something more precise and troubling: in a very particular, lean, metabolically healthy cohort with high LDL after a ketogenic diet, exposure to LDL or ApoB did not clearly predict plaque progression over the observed period, while initial plaque remained the most telling signal. This nuance is crucial.

The simplistic dogma says: high LDL = arteries clogging rapidly. Real biology seems to say: LDL circulates within a terrain. This terrain can be inflammatory, glycated, insulin-resistant, hypertensive, oxidative, or conversely stable, low in triglycerides, high in HDL, low in glucose, low in insulin, with little initial plaque. The same number does not necessarily mean the same trajectory.

This does not grant a license to ignore cardiovascular risk. It demands a smarter reading: imaging, history, blood pressure, ApoB, triglycerides, HDL, insulin, glucose, inflammation, calcification, existing plaque, family context. Metabolic health does not make one immortal. But it can profoundly alter the interpretation of isolated LDL.

And what if the real revolution was not to defend or attack LDL, but to finally demand that cardiovascular risk be assessed in a whole organism, not a single lab value?

#LDL #ApoB #KetoCTA #Carnivore #MetabolicHealth #Atherosclerosis #CoronaryScan #Cholesterol