NMR LipoProfile (Particle Size)
Advanced lipid test using nuclear magnetic resonance technology to measure the number and size of LDL and HDL particles for improved cardiovascular risk assessment beyond traditional cholesterol testing.
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LevelPanel has no business or affiliate relationship with Quest or LabCorp. These links are provided as a public service.
Lab testing services linked from this site are not available to residents of Alaska, Arizona, or Hawaii, unless otherwise noted on the lab's own website.
This publication is not intended to solicit the purchase of laboratory testing from any individual consumer.
What this test measures
The NMR LipoProfile uses nuclear magnetic resonance spectroscopy to analyze lipoprotein particles in a way that standard lipid panels cannot. Rather than simply measuring how much cholesterol is present, it counts the actual number of LDL particles (LDL-P) and characterizes their size distribution. Research has shown that LDL particle number is a stronger predictor of cardiovascular risk than LDL cholesterol concentration alone, because it captures cases where numerous small, dense particles carry the same total cholesterol as fewer large particles but pose significantly more danger.
The test also generates a Lipoprotein Insulin Resistance Index (LP-IR), scored from 0 (most insulin-sensitive) to 100 (most insulin-resistant), derived from the pattern of lipoprotein particle sizes. This metabolic component adds a dimension that no standard lipid panel provides, flagging insulin resistance before it shows up on glucose or A1c testing. Together, the particle data and insulin resistance score give healthcare providers a more granular view of both cardiovascular and metabolic risk.
What's included
Who should consider this test
You might consider this test if you are experiencing any of the following:
- Individuals with a family history of heart disease who want a more detailed assessment of their cardiovascular risk factors, as particle analysis may reveal hidden risks not detected by standard cholesterol testing.
- People with borderline or normal cholesterol levels but other cardiovascular risk factors such as diabetes, metabolic syndrome, or high blood pressure who need a more precise evaluation of their heart disease risk.
- Those with type 2 diabetes or insulin resistance who require advanced monitoring of both cardiovascular and metabolic health markers to guide treatment decisions and lifestyle interventions.
- Patients currently taking cholesterol-lowering medications who want to monitor treatment effectiveness and ensure they are achieving optimal particle reduction goals beyond just cholesterol levels.
- Individuals with unexplained cardiovascular risk or previous heart events who need comprehensive particle analysis to better understand their lipoprotein profile and guide preventive strategies.
What to expect
Preparation
Fast for 12-14 hours before your blood draw. You may drink water during the fasting period. Take medications as prescribed unless your healthcare provider advises otherwise.
Sample Type
A healthcare professional will draw blood from a vein in your arm using a standard needle and collection tube. The process typically takes just a few minutes.
Collection
Visit any participating lab location during business hours. Present your test order and identification. The blood collection is quick and straightforward with minimal discomfort.
Turnaround
Results are typically available within 2-3 business days and will be securely delivered to your online account.
Understanding your results
Results include LDL particle number (LDL-P), particle size breakdown, and the LP-IR insulin resistance score, each with its own reference range. LDL-P is particularly important: an individual can have normal LDL cholesterol but elevated LDL-P, indicating hidden cardiovascular risk that a standard lipid panel would miss. The LP-IR score provides an independent assessment of insulin resistance. Healthcare providers evaluate these results alongside traditional lipid values, glucose and insulin levels, and individual risk factors to build a more complete cardiovascular and metabolic risk profile than cholesterol measurements alone can provide.
| Population | Reference Range | Notes |
|---|---|---|
| Adults | LDL-P: <1,000 nmol/L (desirable), 1,000-1,299 nmol/L (above desirable), 1,300-1,599 nmol/L (borderline high), 1,600-2,000 nmol/L (high), ≥2,000 nmol/L (very high) | LDL particle number is often more predictive of cardiovascular risk than LDL cholesterol alone |
| Adult Males | HDL-P: >30 mcmol/L | Higher HDL particle numbers are associated with better cardiovascular protection |
| Adult Females | HDL-P: >35 mcmol/L | Women typically have higher HDL particle numbers than men |
| Adults | LP-IR Score: 0-100 scale (0 = most insulin sensitive, 100 = most insulin resistant) | Scores below 45 are generally considered below the clinical threshold for insulin resistance |
Reference ranges may vary by laboratory and individual factors. Results should be interpreted by a healthcare provider in the context of your overall health.
What does a “Low” result mean?
Several large clinical studies have shown that HDL-P is more significantly associated with ASCVD risk than HDL cholesterol. Low HDL particle numbers may indicate reduced cardiovascular protection despite normal HDL cholesterol levels. Lower LP-IR scores indicate better insulin sensitivity and reduced metabolic risk. These results should be interpreted alongside other cardiovascular risk factors and clinical history.
What does a “High” result mean?
Elevated LDL particle numbers may indicate increased cardiovascular risk even when cholesterol levels appear normal. More particles mean more chances for them to enter the artery wall and contribute to plaque. Higher LP-IR scores suggest insulin resistance, which can increase the risk of developing type 2 diabetes and cardiovascular disease. Small LDL particle size may indicate a more atherogenic particle profile that could contribute to plaque formation.
Privacy & confidentiality
Your NMR LipoProfile results are completely confidential and protected under HIPAA privacy regulations. Results are not shared with insurance companies, not added to your medical records without your consent, and will not appear on insurance explanation of benefits statements when you pay directly.
Frequently asked questions
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Last reviewed: April 2026
CPT Code: 83704, 80061
This test may not be available in: NY, NJ, RI
This page is for informational purposes only and does not constitute medical advice. Always consult with a healthcare provider regarding any health concerns. LevelPanel does not diagnose, treat, or prescribe.
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LevelPanel has no business or affiliate relationship with Quest or LabCorp. These links are provided as a public service.
Lab testing services linked from this site are not available to residents of Alaska, Arizona, or Hawaii, unless otherwise noted on the lab's own website.
This publication is not intended to solicit the purchase of laboratory testing from any individual consumer.
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