1. What is the Friedewald Formula?

The Friedewald formula is a widely used equation for estimating LDL cholesterol levels from total cholesterol, HDL cholesterol, and triglyceride measurements. It provides a calculated LDL value without requiring direct measurement.

2. How Does the Calculator Work?

The calculator uses the Friedewald formula:

Where:

• Total Cholesterol — Total cholesterol level (mmol/L)
• HDL — High-density lipoprotein cholesterol (mmol/L)
• Triglycerides — Triglyceride level (mmol/L)

Explanation: The formula estimates LDL cholesterol by subtracting HDL and VLDL (estimated as triglycerides divided by 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.

4. Using the Calculator

Tips: Enter total cholesterol, HDL, and triglycerides in mmol/L. All values must be valid (greater than 0). Note: This formula is less accurate when triglyceride levels are above 4.5 mmol/L.

5. Frequently Asked Questions (FAQ)

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

Q2: What are normal LDL values?
A: Optimal LDL is less than 2.6 mmol/L. Borderline high is 2.6-3.3 mmol/L, high is 3.4-4.1 mmol/L, and very high is above 4.1 mmol/L.

Q3: When is the Friedewald formula not accurate?
A: It's less accurate when triglyceride levels exceed 4.5 mmol/L, in non-fasting samples, or in patients with certain metabolic disorders.

Q4: Are there alternative methods for LDL calculation?
A: Yes, direct LDL measurement or the Martin/Hopkins method may be used when triglycerides are elevated or when more precise measurement is needed.

Q5: Should fasting be required for this calculation?
A: Yes, for accurate results, blood should be drawn after a 9-12 hour fast to minimize the effect of recent food intake on triglyceride levels.