{"id":"ldl-size","name":"LDL Particle Size","shortName":"LDL Size","aliases":["LDL Peak Size","LDL Size","LDL Peak Particle Diameter","LDL Peak Diameter","Mean LDL Particle Diameter","LDL Particle Diameter","LDL Particle Size (NMR)","Mean LDL Size","LDL Peak Size (Cardio IQ)","LDL Size (nm)"],"abbreviations":[],"loinc":[{"code":"17782-4","primary":true}],"specimen":"serum-or-plasma","units":[{"ucum":"nm","display":"nm"},{"ucum":"Ao","display":"Å"}],"referenceRanges":[{"population":"Adults","low":20.6,"high":null,"unit":"nm","unitDisplay":"nm","note":"Labcorp's standard NMR LipoProfile prints 'greater than 20.5 nm' (stored as 20.6 because sizes print to one decimal). Labcorp's report with insulin-resistance markers prints '20.8 nm or more', the median of its reference group, so check the range on your own report. Labcorp notes that small LDL size is linked to heart risk but not after LDL particle number is taken into account. Quest's ion mobility report prints size in angstroms with its own cutoffs and does not publish them elsewhere, so none are encoded. NMR and ion mobility sizes are measured differently, so the nm and Å values are not interchangeable between methods.","sources":[{"title":"NMR LipoProfile+Lipids+Graph, sample patient report (test 123810)","url":"https://files.labcorp.com/testmenu-d8/sample_reports/123810.pdf","publisher":"Labcorp","year":2024},{"title":"NMR LipoProfile+IR+Graph, sample patient report (test 123497)","url":"https://files.labcorp.com/testmenu-d8/sample_reports/123497.pdf","publisher":"Labcorp","year":2024}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"The typical width of your LDL particles. Small LDL goes with high triglycerides and insulin resistance, but size adds little once your particle count is known.","url":"https://bloodtesttracker.com/markers/ldl-size","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}