1. What is the LDL Calculation Formula?

The Friedewald formula calculates LDL cholesterol from total cholesterol, HDL, and triglycerides. It provides a practical estimation of LDL levels without requiring direct measurement.

2. How Does the Calculator Work?

The calculator uses the Friedewald formula:

Where:

• Total Cholesterol — Total cholesterol level (mg/dL)
• HDL — High-density lipoprotein level (mg/dL)
• Triglycerides — Triglycerides level (mg/dL)

Explanation: The formula estimates LDL cholesterol by subtracting HDL and VLDL (estimated as triglycerides/5) from total cholesterol.

3. Importance of LDL Calculation

Details: LDL cholesterol is a major risk factor for cardiovascular disease. Accurate estimation helps assess cardiovascular risk and guide treatment decisions.

4. Using the Calculator

Tips: Enter total cholesterol, HDL, and triglycerides in mg/dL. All values must be valid (greater than 0). Note: This formula is less accurate when triglycerides exceed 400 mg/dL.

5. Frequently Asked Questions (FAQ)

Q1: Why use the Friedewald formula?
A: It provides a cost-effective estimation of LDL without requiring direct measurement, making it widely used in clinical practice.

Q2: What are normal LDL values?
A: Optimal LDL is less than 100 mg/dL. Near optimal is 100-129 mg/dL, borderline high is 130-159 mg/dL, high is 160-189 mg/dL, and very high is 190 mg/dL and above.

Q3: When should lipid levels be measured?
A: Fasting for 9-12 hours is recommended for accurate triglyceride measurement, which affects LDL calculation.

Q4: Are there limitations to this formula?
A: Less accurate when triglycerides exceed 400 mg/dL, in non-fasting samples, or in certain conditions like diabetes and chronic kidney disease.

Q5: When is direct LDL measurement preferred?
A: Direct measurement is recommended when triglycerides are very high (>400 mg/dL) or when more precise LDL assessment is needed.