Every particle that can lodge in an artery wall carries exactly one ApoB protein. Measuring ApoB is therefore a direct count of the particles that drive atherosclerosis.
Why LDL-C can mislead
LDL-C measures the cholesterol inside particles, not the number of particles. In people with insulin resistance, LDL-C can look normal while particle count is high.
What's a good level?
Guidelines vary. Many preventive specialists aim for lower values in higher-risk patients. Your target depends on your overall risk — discuss with your clinician.
How often to test
Monthly or quarterly testing is useful when you change diet, start a statin, or begin a GLP-1. Otherwise once or twice a year is common.