Total Serum Cholesterol (TC)
Total cholesterol measures the aggregate mass of cholesterol carried across all circulating lipoprotein classes including HDL, LDL, IDL, and VLDL.
Standard vs. Optimal Reference Rangesmg/dL
Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.
Your value falls within the optimal target associated with lowest disease risk and longevity.
< 200 mg/dL
General reference distribution across unselected commercial populations.
150 - 190 mg/dL (interpreted in context of ApoB)
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
Cholesterol is a 27-carbon sterol synthesized de novo from acetyl-CoA via the rate-limiting enzyme HMG-CoA reductase. It serves as an essential structural component of cell membranes and the precursor for steroid hormones, vitamin D, and bile acids.
Differential Diagnosis
Elevated Levels (TC High)
- •Familial hypercholesterolemia
- •Biliary obstruction
- •Hypothyroidism
- •Cushing syndrome
Low Levels (TC Low)
- •Severe hepatic insufficiency
- •Malabsorption / Malnutrition
- •Hyperthyroidism
- •Advanced malignancy cachexia
Technical Reference & Deep Dive
Biochemistry & Enzymatic Pathways
Longevity Risk Architecture & Epidemiology
Pre-Analytical Caveats & Diagnostic Workup
Pre-Analytical Considerations:
Standard testing requires a 10 to 12 hour overnight fast to minimize postprandial chylomicron interference, although TC direct immunoassay is less sensitive to prandial state than calculated LDL-C. Avoid strenuous high-intensity exercise 24 hours prior to blood draw. Serum separator tubes (SST) or EDTA plasma should be centrifuged within 2 hours. High-dose biotin (>5 mg/day) supplementation may interfere with competitive streptavidin-biotin immunoassays, requiring a 48-hour washout period.
Reflexive Testing Protocol:
- Advanced Lipoprotein Particle Quantification (NMR spectroscopy or ion mobility LDL-P)
- Lipoprotein(a) [Lp(a)] baseline evaluation for genetic cardiovascular risk stratification
- Coronary Artery Calcium (CAC) score via non-contrast cardiac CT to evaluate calcified plaque burden
- High-sensitivity C-Reactive Protein (hs-CRP) to assess systemic vascular inflammatory tone
- Carotid intima-media thickness (CIMT) duplex ultrasound to assess subclinical atherosclerosis
Clinical Citations & Primary Literature (1)
- [1]Global Burden of Cardiovascular Diseases and Risk Factors - JACC (2022). PMID: 33309175
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Total Serum Cholesterol (TC) into overall healthspan optimization.