1. What is the LDL Cholesterol Calculation?

The LDL cholesterol calculation using the formula LDL = TC - HDL - (TG / 2.2) provides an estimated value for low-density lipoprotein cholesterol. This calculation is particularly useful when direct LDL measurement is not available or when triglycerides are below 4.5 mmol/L.

2. How Does the Calculator Work?

The calculator uses the LDL formula:

Where:

• \( TC \) — Total cholesterol (mmol/L)
• \( HDL \) — HDL cholesterol (mmol/L)
• \( TG \) — Triglycerides (mmol/L)

Explanation: This formula estimates LDL cholesterol by subtracting HDL and VLDL (estimated as TG/2.2) from total cholesterol.

3. Importance of LDL Calculation

Details: LDL cholesterol is a major risk factor for cardiovascular disease. Accurate estimation helps in assessing cardiovascular risk and guiding treatment decisions for cholesterol management.

4. Using the Calculator

Tips: Enter total cholesterol, HDL, and triglycerides in mmol/L. All values must be positive numbers. This calculation is most accurate when triglycerides are below 4.5 mmol/L.

5. Frequently Asked Questions (FAQ)

Q1: Why divide triglycerides by 2.2?
A: The factor 2.2 (or 5 in mg/dL units) approximates the cholesterol content in VLDL particles, which is estimated as TG/2.2 in mmol/L.

Q2: When is this calculation not accurate?
A: This formula becomes less accurate when triglycerides exceed 4.5 mmol/L, in non-fasting samples, or in certain metabolic disorders.

Q3: What are optimal LDL levels?
A: Optimal LDL is generally below 2.6 mmol/L for most adults, and below 1.8 mmol/L for high-risk patients.

Q4: Should I fast before testing?
A: Yes, for accurate results, fast for 9-12 hours before lipid testing to avoid triglyceride elevation from recent meals.

Q5: How often should LDL be checked?
A: Adults should have lipid profiles checked every 4-6 years, or more frequently if risk factors exist or treatment is ongoing.