Empeiria

Cholesterol, total

Also known as TC, total cholesterol

C₂₇H₄₆O small molecule

LOINC 2093-3 code verified serum mg/dL

What this substance is

formula
C₂₇H₄₆O
mass
386.664 g/mol
monoisotopic
386.35487
charge
0
InChIKey
HVYWMOMLDIMFJA-DPAQBDIFSA-N
ChEBI
CHEBI:16113
CAS
57-88-5

Drawn from ChEBI's own curated 2D drawing, accepted only after its InChIKey, formula and charge matched the ChEBI release. Nothing here is hand-entered. Two masses are given because they answer different questions: the average is natural-abundance weighted and drives unit conversion; the monoisotopic value uses only the commonest isotope of each element and is what mass spectrometry measures.

3D model · Cholesterol, total

Generated by RDKit from ChEBI's verified structure, and accepted only because its own 3D geometry reproduces ChEBI's InChIKey. A flexible molecule takes many shapes; this is one low-energy one. Drag to rotate, scroll to zoom.

Reference ranges

Checking your own result against this range needs the running application; this is a static copy. Nothing you type anywhere in Empeiria is ever sent to a server.

all
200
normal range · mg/dL
Applies toNormalOptimalCritical
all ≤ 200 mg/dL — —

guideline limit ATP III Guidelines At-A-Glance Quick Desk Reference, National Cholesterol Education Program (NHLBI) cited · not yet checked by a person

How it is measured

In practice

A health worker takes a small blood sample from a vein in your arm with a needle. You may need to skip food and drink for 9 to 12 hours, so the test is often done in the morning. Home kits also exist: you prick your finger for a drop of blood. Tell your provider if a home test shows total cholesterol above 200 mg/dL.

Usually measured within a lipid panel (lipid profile) on serum or plasma from venipuncture; EDTA and heparin plasma are acceptable, but EDTA gives results about 3-6% lower than serum. Patients may be asked to fast 9 to 12 hours, which is why testing is often done in the morning. At-home fingerstick kits are available; a home total cholesterol above 200 mg/dL should be reported to the provider.

Before the test

  • Fast (no food or drink) for 9 to 12 hours if your provider tells you to.

Where: laboratory, home

Sources: Cholesterol Levels, MedlinePlus (U.S. National Library of Medicine); NHANES 2017-2018 Laboratory Procedure Manual, Total Cholesterol (CDC National Center for Health Statistics) cited · not yet checked by a person

In the lab

enzymatic colorimetric

Cholesterol oxidase / esterase

Most cholesterol in blood is attached to other molecules. One enzyme cuts it free and a second reacts with it to produce a colour.

Cholesterol esterase releases free cholesterol from its esters; cholesterol oxidase then generates hydrogen peroxide for a Trinder endpoint.

  • Read by: Absorbance at 500 nm
  • Standardised to: CDC Lipid Standardization Program
Why labs disagree: NCEP guidelines set fixed decision points for total cholesterol (for example "desirable" below 200 mg/dL). Those decision points came from CDC population studies standardised to the Abell-Kendall reference method, so a lab's method must be standardised and harmonised to use them. External quality assessment still finds differences in results across manufacturers, and calibrator traceability may be one cause.

Sources: NHANES 2017-2018 Laboratory Procedure Manual, Total Cholesterol, CDC/NCHS; Standardization Status of Total Cholesterol Concentration Measurement: Analysis of Korean External Quality Assessment Data. Ann Lab Med 2021 (PMC7884189) cited · not yet checked by a person

What it reports on

Associated symptoms

Conditions this marker features in

When high
  • high Unhealthy cholesterol levels · defining
    Classification, not a single diagnostic test: in the NCEP ATP III scheme a total cholesterol of 240 mg/dL or more is 'high' (200–239 borderline high).
  • high Mildly underactive thyroid · supportive
    Study results are mixed. Some find higher total cholesterol, rising with TSH; one large study found it only in women.
  • high Underactive thyroid · supportive
    Hypothyroidism raises total and LDL cholesterol; people with high cholesterol are advised to be tested for it.

Ordered as part of

lipid