1. What is LDL Cholesterol?

LDL (low-density lipoprotein) cholesterol, often called "bad" cholesterol, contributes to fatty buildups in arteries (atherosclerosis). This narrows the arteries and increases risk for heart attack, stroke and peripheral artery disease.

2. How Does the Calculator Work?

The calculator uses the Friedewald formula:

Where:

• \( TC \) — Total cholesterol (mg/dL)
• \( HDL \) — HDL cholesterol (mg/dL)
• \( TG \) — Triglycerides (mg/dL)

Note: This formula is valid only when triglycerides are below 400 mg/dL. For higher values, direct LDL measurement is needed.

3. Importance of LDL Calculation

Details: LDL cholesterol is a major risk factor for cardiovascular disease. Monitoring and managing LDL levels is crucial for preventing heart attacks and strokes.

4. Using the Calculator

Tips: Enter all values in mg/dL. The calculation requires fasting lipid panel results (9-12 hour fast). Non-fasting samples may affect triglyceride levels and thus LDL calculation.

5. Frequently Asked Questions (FAQ)

Q1: What are optimal LDL levels?
A: Optimal is <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.

Q2: Why divide triglycerides by 5?
A: This estimates VLDL cholesterol (very low-density lipoprotein), as VLDL carries most triglycerides in fasting blood.

Q3: When is this formula not accurate?
A: When triglycerides are ≥400 mg/dL, in non-fasting states, or with certain conditions like type III hyperlipidemia.

Q4: How often should LDL be checked?
A: Adults should have lipid panel every 4-6 years. Those with risk factors may need more frequent testing.

Q5: What lowers LDL cholesterol?
A: Lifestyle changes (healthy diet, exercise, weight loss) and medications (statins, PCSK9 inhibitors, ezetimibe) can effectively lower LDL.