1. What is the Friedewald Equation?

The Friedewald equation is a formula used to estimate LDL cholesterol levels without requiring direct measurement. It's calculated using total cholesterol, HDL cholesterol, and triglyceride values.

2. How Does the Calculator Work?

The calculator uses the Friedewald equation:

Where:

• \( LDL \) — Low-density lipoprotein cholesterol (mmol/L)
• \( TC \) — Total cholesterol (mmol/L)
• \( HDL \) — High-density lipoprotein cholesterol (mmol/L)
• \( TG \) — Triglycerides (mmol/L)

Explanation: The equation 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 often called "bad cholesterol" as high levels are associated with increased risk of cardiovascular disease. Monitoring LDL levels is crucial for heart health management.

4. Using the Calculator

Tips: Enter total cholesterol, HDL cholesterol, and triglyceride values in mmol/L. All values must be valid (greater than 0). Note that this calculation is not accurate when triglyceride levels exceed 4.5 mmol/L.

5. Frequently Asked Questions (FAQ)

Q1: Why is 3.3 mmol/L considered borderline high for LDL?
A: LDL levels between 3.3-4.1 mmol/L are considered borderline high, indicating increased risk for cardiovascular disease.

Q2: When is the Friedewald equation not accurate?
A: The equation is less accurate when triglyceride levels exceed 4.5 mmol/L, in non-fasting samples, or in certain medical conditions.

Q3: What are the limitations of calculated LDL?
A: Direct measurement may be needed for patients with high triglycerides, diabetes, or very low LDL levels.

Q4: How often should LDL be checked?
A: Adults should have cholesterol checked every 4-6 years, or more frequently if risk factors are present.

Q5: What factors can affect LDL levels?
A: Diet, exercise, genetics, medications, and certain medical conditions can all influence LDL cholesterol levels.