Low-Density Lipoprotein Cholesterol, Serum/Plasma — Substance Concentration
This blood test measures LDL (“bad”) cholesterol, a lipid that builds up in artery walls and is associated with increased cardiovascular risk.
["LDL cholesterol helps assess cardiovascular risk and is often interpreted with total cholesterol, HDL cholesterol, and triglycerides."]
Key facts at a glance
- LOINC
- 22748-8
- Short code
- LDLc SerPl-sCnc
- Synonyms
- LDLc SerPl-sCnc
- Category
- lipid
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 100
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 83721
- SNOMED
- 113079007
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test measures the amount of low-density lipoprotein cholesterol in blood. LDL is often called “bad” cholesterol because it can contribute to fatty plaque buildup in arteries.
Why might I need this test?
A clinician may order LDL cholesterol to assess cardiovascular risk, guide cholesterol management, or monitor treatment for high cholesterol. It is commonly part of a lipid panel.
How is the test performed?
A blood sample is drawn from a vein and analyzed in a laboratory to determine the LDL cholesterol concentration. It may be measured directly or calculated from other results in a lipid panel, depending on the laboratory method.
How do I prepare for the test?
Follow the instructions provided by your clinician. Some lipid tests are ordered after fasting, while others do not require it, and food and drinks can affect cholesterol measurements.
Reference range
Optimal: <100 mg/dLN/A
Fasting for 12-14 hours preferred. Water is permitted. Avoid alcohol for 24 hours before the test.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A higher LDL cholesterol result is associated with increased risk of atherosclerotic cardiovascular disease, which can include heart attack and stroke. A lower result generally indicates a lower level of circulating LDL cholesterol, but interpretation depends on your overall risk factors and medical history. The result is best reviewed with a clinician alongside HDL cholesterol, triglycerides, and other cardiovascular risk factors.
Short name
LDL cholesterol
Frequently asked questions
Does this test require fasting?
Is LDL cholesterol the same as “bad” cholesterol?
Can I lower LDL cholesterol?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy