Study analysis · JACC: Advances · 2024

Some people on keto have LDL cholesterol over 500 mg/dL—yet their arteries show no more plaque than people with normal cholesterol.

Healthy people on keto with super high cholesterol don’t have more heart plaque than those with low cholesterol.

Reading level
Low certainty
Level 2b · Individual cohort studyAssociation, not causationNo causal claims

Overview

What the study found

The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.

In simple terms

This study looks at two groups of people — some on a keto diet with very high cholesterol and others with normal cholesterol — and checks their heart arteries for plaque. It found no difference in plaque between them, but because it didn’t randomly assign people to diets, we can’t say the keto diet caused no harm or benefit — only that there’s no link seen here.

What’s the bottom line?

This study looked at healthy, lean people who eat a keto diet and have very high cholesterol. It checked if they had more plaque in their heart arteries than similar people with normal cholesterol.

How strong is this study?

The study compared similar people using detailed heart scans, which is good. But we don’t know all the details about how it was done because the full paper isn’t available, and it didn’t randomly assign diets, so we have to be careful not to jump to conclusions.

Reporting

0 / 100

  • COI disclosureconflicts of interest not disclosed
  • Data availabilitydata not shared
  • Code availabilitycode not shared
Methodology

45 / 100

  • Randomizationrandomization unclear
  • Blindingblinding unclear
  • Control group+15/15
  • Sample size (n=160)+11.0/20
  • Follow-up+10/10
Publication

100 / 100

Statistical

46 / 100

  • P-values+15/15
  • Effect sizeno effect size reported
  • Confidence intervals+15/15
  • Pre-registrationnot pre-registered

Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.

Where it sits

RCT reviews

Max 100

Randomized Trials

Max 90

Reviews of Cohort Studies

Max 85

Cohort Studies

Max 72

Reviews of Case-Control Studies

Max 63

Case-Control Studies

Max 58

Cross-Sectional & Case Series

Max 50

Expert Opinion

Max 5
StrongerWeaker
Cohort Studies
Level 2b
47

47 / 100

Probability of being correct

Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.

This design cannot establish causation — the findings describe an association, not a cause. Study is observational (cohort) with no explicit mention of randomization in the abstract; therefore, it cannot support causal claims. Confounding factors may influence results.

Key takeaways

  1. 01

    80 keto eaters had LDL up to 591 mg/dL.

  2. 02

    Their heart plaque levels were not higher than 80 others with LDL around 123 mg/dL.

  3. 03

    Half had zero plaque in both groups.

  4. 04

    Even very high LDL from a keto diet may not lead to more heart plaque in healthy, lean people over nearly 5 years.

Surprising findings

  • No significant difference in coronary plaque despite a 149 mg/dL difference in average LDL-C between groups.Standard cardiovascular guidelines assume higher LDL-C directly increases atherosclerosis risk. This study found no such effect in lean, healthy keto eaters—even with LDL levels considered extremely high.
  • No correlation between LDL-C level and plaque burden in the keto group.This contradicts the widely accepted 'lower is better' model of LDL-C and heart disease, at least in this population.

Practical takeaways

If you're lean, metabolically healthy, and on a ketogenic diet with high LDL, this study suggests your artery health may still be normal.

This does not prove long-term safety, and findings are limited to imaging over ~5 years. Full methodology and long-term outcomes are unknown.

low confidence

Consider coronary artery calcium or CCTA scanning if you have diet-induced high LDL and want to assess actual plaque, not just risk estimates.

Imaging has costs and radiation exposure; not recommended for everyone. This study only looked at a specific subgroup.

low confidence

Why this study matters

The Keto Paradox

The study looked at 80 lean, metabolically healthy people on long-term ketogenic diets with LDL-C as high as 591 mg/dL (average 272 mg/dL). Despite these extremely high levels—far above typical heart disease risk thresholds—they had no more coronary plaque than 80 matched controls with LDL-C around 123 mg/dL.

This challenges the common belief that very high LDL always means higher heart disease risk, suggesting context like diet and metabolic health may matter more than the number alone.

No Link Between LDL and Plaque in Keto Users

In the ketogenic diet group, there was no correlation between LDL-C levels and coronary plaque burden measured by CCTA. Even individuals with LDL-C over 500 mg/dL had plaque levels similar to those with much lower cholesterol.

It suggests that for some people, especially those who are lean and metabolically healthy, LDL may not be a reliable predictor of heart disease risk.

Half Had Zero Plaque—Even with Sky-High LDL

Half of the keto group had zero coronary artery calcium and zero total plaque on CCTA—despite an average LDL of 272 mg/dL and some exceeding 500 mg/dL. The control group had similar results.

This shows that having very high LDL doesn’t automatically mean artery damage, at least in this specific group of healthy individuals.

Want the whole report?

Detailed mode opens the full scientific breakdown — every score component, the methodology, conflicts of interest, the evidence analysis behind each claim, and the raw study data.

Standing

Who’s using this study?

The videos and claims on this site that lean on this study, and the researchers who wrote it.

1 video from Dr Brad Stanfield cite this study, drawing 1 claim from it.

All 1 video reference this study through extracted claims.

Authored by

10 researchers

If this is your work, this is how we attribute it on Fit Body Science. Matthew Jay Budoff is listed as the lead author.