Triglycerides: Why do they matter?

Triglycerides are an important measure of heart health. Here's why triglycerides matter — and what to do if your triglycerides are too high. By Mayo Clinic Staff

If you've been keeping an eye on your blood pressure and cholesterol levels, there's something else you might need to monitor: your triglycerides. Having a high level of triglycerides, a type of fat (lipid) in your blood, can increase your risk of heart disease. However, the same lifestyle choices that promote overall health can help lower your triglycerides, too.

What are triglycerides?

Triglycerides are a type of fat (lipid) found in your blood. When you eat, your body converts any calories it doesn't need to use right away into triglycerides. The triglycerides are stored in your fat cells. Later, hormones release triglycerides for energy between meals. If you regularly eat more calories than you burn, particularly "easy" calories like carbohydrates and fats, you may have high triglycerides (hypertriglyceridemia).

What's considered normal?

A simple blood test can reveal whether your triglycerides fall into a healthy range.

  • Normal — Less than 150 milligrams per deciliter (mg/dL), or less than 1.7 millimoles per liter (mmol/L)
  • Borderline high — 150 to 199 mg/dL (1.8 to 2.2 mmol/L)
  • High — 200 to 499 mg/dL (2.3 to 5.6 mmol/L)
  • Very high — 500 mg/dL or above (5.7 mmol/L or above)

The American Heart Association (AHA) recommends that a triglyceride level of 100 mg/dL (1.1 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. That's because triglycerides usually respond well to dietary and lifestyle changes.

Your doctor will usually check for high triglycerides as part of a cholesterol test (sometimes called a lipid panel or lipid profile). You'll have to fast for nine to 12 hours before blood can be drawn for an accurate triglyceride measurement.

What's the difference between triglycerides and cholesterol?

Triglycerides and cholesterol are separate types of lipids that circulate in your blood. Triglycerides store unused calories and provide your body with energy, and cholesterol is used to build cells and certain hormones. Because triglycerides and cholesterol can't dissolve in blood, they circulate throughout your body with the help of proteins that transport the lipids (lipoproteins).

Sep. 28, 2012 See more In-depth