By Mayo Clinic News Network

It's important to keep your cholesterol levels within healthy limits. If you have other risk factors for developing heart disease, you need to be even more careful — especially with your low-density lipoprotein (LDL), or "bad," cholesterol level.

Interpreting your cholesterol numbers

Cholesterol levels are measured in milligrams (mg) of cholesterol per deciliter (dL) of blood in the United States and some other countries. Canada and most European countries measure cholesterol in millimoles (mmol) per liter (L) of blood. Consider these general guidelines when you get your cholesterol test (lipid panel or lipid profile) results to see if your cholesterol falls in an ideal range.

Total cholesterol
(U.S. and some other countries)
Total cholesterol*
(Canada and most of Europe)
 
Below 200 mg/dLBelow 5.2 mmol/LDesirable
200-239 mg/dL5.2-6.2 mmol/LBorderline high
240 mg/dL and aboveAbove 6.2 mmol/LHigh

 

LDL cholesterol
(U.S. and some other countries)
LDL cholesterol*
(Canada and most of Europe)
 
Below 70 mg/dLBelow 1.8 mmol/LIdeal for people at very high risk of heart disease
Below 100 mg/dLBelow 2.6 mmol/LIdeal for people at risk of heart disease
100-129 mg/dL2.6-3.3 mmol/LNear ideal
130-159 mg/dL3.4-4.1 mmol/LBorderline high
160-189 mg/dL4.1-4.9 mmol/LHigh
190 mg/dL and aboveAbove 4.9 mmol/LVery high

 

HDL cholesterol
(U.S. and some other countries)
HDL cholesterol*
(Canada and most of Europe)
 
Below 40 mg/dL (men)
Below 50 mg/dL (women)
Below 1 mmol/L (men)
Below 1.3 mmol/L (women)
Poor
40-49 mg/dL (men)
50-59 mg/dL (women)
1-1.3 mmol/L (men)
1.3-1.5 mmol/L (women)
Better
60 mg/dL and above1.6 mmol/L and aboveBest

 

Triglycerides
(U.S. and some other countries)
Triglycerides*
(Canada and most of Europe)
 
Below 150 mg/dLBelow 1.7 mmol/LDesirable
150-199 mg/dL1.7-2.2 mmol/LBorderline high
200-499 mg/dL2.3-5.6 mmol/LHigh
500 mg/dL and aboveAbove 5.6 mmol/L and aboveVery high

*Canadian and European guidelines differ slightly from U.S. guidelines. These conversions are based on U.S. guidelines.

The American Heart Association (AHA) recommends that a triglyceride level of 100 mg/dL (1.3 mmol/L) or lower is considered optimal. The AHA says this optimal level would improve your heart health. However, the AHA doesn't recommend drug treatment to reach this level. Instead, for those trying to lower their triglycerides to this level, lifestyle changes such as diet, weight loss and physical activity are encouraged. Elevated triglycerides usually respond well to dietary and lifestyle changes.

LDL targets differ

Because LDL cholesterol is a major risk factor for heart disease, it's the main focus of cholesterol-lowering treatment. Your target LDL number can vary, depending on your underlying risk of heart disease.

Most people should aim for an LDL level below 130 mg/dL (3.4 mmol/L). If you have other risk factors for heart disease, your target LDL may be below 100 mg/dL (2.6 mmol/L). If you're at very high risk of heart disease, you may need to aim for an LDL level below 70 mg/dL (1.8 mmol/L). In general, the lower your LDL cholesterol level is, the better. There is no evidence that really low LDL cholesterol levels are harmful.

You're considered to be at a high risk of heart disease if you have or have had any of the following:

  • A previous heart attack or stroke
  • Artery blockages in your neck (carotid artery disease)
  • Artery blockages in your arms or legs (peripheral artery disease)
  • Diabetes

In addition, two or more of the following risk factors also might place you in the very high risk group:

  • Smoking
  • High blood pressure
  • Low HDL cholesterol
  • Family history of early heart disease
  • Age older than 45 if you're a man, or older than 55 if you're a woman
  • Elevated lipoprotein (a), another type of fat (lipid) in your blood