1. What is LDL-C Calculation?

The Friedewald formula calculates LDL cholesterol (LDL-C) from total cholesterol, HDL cholesterol, and triglycerides. This calculation provides an estimate of "bad" cholesterol levels, which is important for assessing cardiovascular risk.

2. How Does the Calculator Work?

The calculator uses the Friedewald formula:

Where:

• \( LDL-C \) — Low-density lipoprotein cholesterol (mg/dL)
• \( TC \) — Total cholesterol (mg/dL)
• \( HDL-C \) — High-density lipoprotein cholesterol (mg/dL)
• \( TG \) — Triglycerides (mg/dL)

Explanation: This formula estimates LDL cholesterol without requiring direct measurement, making it a cost-effective screening tool.

3. Meaning of High LDL-C

Details: Elevated LDL cholesterol is a major risk factor for cardiovascular disease. High levels contribute to plaque buildup in arteries (atherosclerosis), increasing risk of heart attack and stroke.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: What is considered high LDL cholesterol?
A: Generally, LDL-C above 160 mg/dL is considered high, 130-159 mg/dL is borderline high, and optimal is below 100 mg/dL (or below 70 mg/dL for high-risk patients).

Q2: Why is high LDL dangerous?
A: High LDL contributes to plaque formation in arteries, narrowing blood vessels and increasing risk of heart disease, heart attack, and stroke.

Q3: When should this calculation not be used?
A: The Friedewald formula is inaccurate when triglycerides exceed 400 mg/dL, in non-fasting samples, or in certain conditions like type III hyperlipoproteinemia.

Q4: How can I lower my LDL cholesterol?
A: Lifestyle changes include healthy diet (low saturated/trans fats), regular exercise, weight management, and if needed, cholesterol-lowering medications.

Q5: Should I fast before cholesterol testing?
A: For accurate results, fast for 9-12 hours before blood draw to avoid temporary increases in triglycerides that affect LDL calculation.