KETO-CTA Study — Findings Presented by Dave Feldman (Interview with Dr. Ken Berry)

Core Questions Raised

• Does high LDL cholesterol or high ApoB, especially on ketogenic/carnivore diets, accelerate coronary plaque formation?
• What happens to plaque burden when people maintain very high LDL for years on low-carb diets?

Study Overview (as described)

• Design: Coronary CT angiography (CCTA) scans analyzed for plaque burden; scans compared across time.
• Cohort size: ~100 participants discussed.
• Diet: Low-carb / ketogenic (includes lean-mass hyper-responders).
• Exposure duration mentioned: Multi-year follow-up; “nearly half a decade” (~4.5 years) cited in discussion for average exposure at very high LDL levels.
• Baseline CAC: Majority reported as CAC=0 at baseline.
• Age: Average age stated as ~55 years.

LDL/ApoB & Who Elevates Most on Keto

• LDL/ApoB rises are most prominent in leaner individuals; a “1–5%” subgroup can see marked increases (lean-mass hyper-responders).
• Overweight individuals starting keto more often see LDL fall or change minimally as metabolic health improves.

Imaging & Analysis Pipelines Used

• Multiple, independent quantification routes were used on the same CCTA datasets:
  • Cleerly (AI plaque quantification).
  • HeartFlow.
  • QAngio.
  • A semi-quantitative visual method.
• Quality control / usability rates differed by tool on identical scans:
  • Example figures mentioned: HeartFlow ~6.3%, QAngio ~39.8% (context: differing pass/fail or exclusion proportions across analyses).
• Key metric emphasized: Percent Atheroma Volume (PAV); also total plaque volume and non-calcified vs calcified plaque were discussed.
• A specific change example cited: Cleerly ~+23.3 mm³ (small absolute change) in a reported plaque volume metric.

Main Findings Reported

• Progression signals were low overall across the cohort despite very high LDL/ApoB levels on long-term low-carb/keto.
• Some participants showed regression (less plaque at follow-up than baseline).
• Results were directionally consistent across analysis methods, despite different exclusion/quality rates.
• Emphasis that non-calcified plaque (considered more concerning) did not show worrisome acceleration cohort-wide.

Clinical Events Mentioned

• Among ~100 people followed/discussed, no heart attacks were reported within the study’s observation window.

Radiation & Practical Notes on CCTA

• Modern CCTA was described as low-dose radiation, with a figure around ~0.6 mSv mentioned.
• Dosing framed as roughly ~1.5× a mammogram (comparative remark).
• Procedure described: IV contrast to opacify coronary lumens; modern detectors/software reduce needed dose.

Limitations Acknowledged (as discussed)

• Not a randomized trial; observational cohort with multi-tool re-analysis for robustness.
• Different software pipelines yield different exclusion rates and require careful quality control.
• Calls for larger, head-to-head prospective studies (e.g., vegan vs carnivore cohorts) were explicitly voiced.

Takeaways Stated in the Video

• In a keto/carnivore cohort with very high LDL/ApoB and ~4.5 years average exposure, plaque progression was minimal on average, with some regressors, and no heart attacks recorded in the observed period.
• Multiple independent analytic methods—despite differing QC pass rates—converged on low progression signals.