Cholesterol (Total) in Serum
This test measures the total amount of cholesterol in your blood serum. Cholesterol is a type of fat that your body needs for many functions, but having too much can increase your risk of heart disease.
["Your blood cholesterol levels help assess heart health risk."]
Key facts at a glance
- LOINC
- 102240-9
- Short code
- CLAH IgE
- Synonyms
- C herbarum IgE RAST
- Category
- chemistry
- Sample
- serum
- Container
- Red-top serum collection tube or serum separator tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 0.35
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- Radioallergosorbent test (RAST)
- CPT
- 86003
- SNOMED
- 39579001
- Specimen volume
- 1 mL serum (minimum 0.5 mL)
- Stability
- Stable for 7 days at 2-8°C; stable for 1 month at -20°C; avoid repeated freeze-thaw cycles
- Hemolysis max
- 100
- Lipemia max
- 300
- Icterus max
- 50
- TAT
- 24–72 hours
- Order
- routine
Why This Test Matters
Cholesterol is a vital substance your body uses to build cell membranes, produce hormones, and make vitamin D. However, too much cholesterol in your blood can build up in your arteries, leading to blockages that may cause heart attacks or strokes. This test helps doctors monitor your cholesterol levels to prevent these health issues.
What to Expect Before the Test
No special preparation is needed for this test. You may have a blood draw from a vein in your arm, similar to other blood tests. If you’re on blood thinners or have a history of bleeding disorders, let your healthcare provider know before the test.
How the Test Works
A small sample of your blood is collected and sent to a lab. The lab uses a chemical method to measure the total cholesterol content in your serum. This includes both low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, as well as triglycerides.
What the Results Mean
Your results will show your total cholesterol level, but they won’t break it down into LDL, HDL, or triglycerides unless specifically requested. High total cholesterol levels (above normal ranges) may indicate an increased risk of heart disease, while lower levels may suggest better cardiovascular health. Your doctor will interpret these results in the context of your overall health.
Reference range
Negative (≤0.35 kU/L); Class 0: Absent/Undetectable. Classes 1-6 may indicate increasing sensitization.N/A
No fasting required. Patient should inform clinician of all current medications, especially antihistamines (though these do not affect IgE antibody levels in serum). Avoid recent blood transfusion if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Total Cholesterol
Frequently asked questions
What does a high total cholesterol level mean?
Can low cholesterol levels be harmful?
How often should I get this test?
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 17, 2026. · Read our editorial policy