Triglycerides

What is being tested?
This test gives the concentration of triglycerides in the blood. Triglycerides are the main form in which fat is stored in our body and a key energy source; they build up mainly in adipose tissue and the liver. Triglycerides can also be found in the circulation at high concentrations, for example after a large meal. For this reason, to detect any abnormalities in fat metabolism, the blood sample for triglycerides must be taken after fasting for at least 8 hours.

How is the sample collected for testing?
The sample is taken from a vein in the arm.

How is it used?
When is it requested?
What does the test mean?
Is there anything else I should know?

How is it used?
Triglycerides are usually included in the lipid profile used to assess the risk of cardiovascular disease. In people with diabetes, especially if blood sugar is poorly controlled, high triglycerides are a common finding.

When is it requested?
The lipid profile, which includes triglycerides, is prescribed in adults to assess the risk of cardiovascular disease. Triglycerides are rarely prescribed outside a lipid profile: this may happen when the patient is taking triglyceride-lowering medicines, to monitor that treatment.

What does the test mean?
The reference value for triglycerides is < 160 mg/dl. High triglycerides are often associated with other lipid metabolism abnormalities, such as low HDL cholesterol and high LDL; the choice of lipid-lowering medicine must take all these abnormalities into account.

Is there anything else I should know?
The blood sample for triglycerides must be taken after fasting for at least 8-10 hours; it is also advisable not to drink alcohol in the 24 hours before the test.

High triglycerides are common in poorly controlled diabetes.

Blood triglyceride levels vary considerably in relation to meals: after a large meal, the value is normally 5-10 times higher than the fasting value. In addition, the fasting value can vary significantly from day to day, so modest changes in triglycerides over time are considered normal.

1. What is the best diet for keeping triglycerides at acceptable levels?
2. Which medicines are used to treat high triglycerides?
3. Does exercise help keep triglycerides at acceptable levels?
4. Are there POCT devices for measuring triglycerides at home?
5. What are VLDL and how are they related to triglycerides?

1. What is the best diet for keeping triglycerides at acceptable levels?
A low-fat diet certainly helps; remember, however, that too much carbohydrate, especially simple sugars, can also raise blood triglycerides.

2. Which medicines are used to treat high triglycerides?
High triglycerides are often secondary to other disorders, such as diabetes, obesity, kidney failure and alcoholism; in this case treatment is aimed at the underlying condition. In primary hypertriglyceridaemia, however, fibrates may be useful. Medicines are, in any case, reserved for cases in which a controlled lifestyle (mainly a low-fat diet and regular exercise) is not enough.

3. Does exercise help keep triglycerides at acceptable levels?
Yes. Exercise is particularly useful for lowering triglycerides and raising HDL cholesterol (which tends to fall when triglycerides rise), even if it does not lead to weight loss: the metabolic changes brought about by exercise reflect better use of the body’s energy sources. In people with diabetes, who often have high triglycerides, especially when their diabetes is poorly controlled, exercise is also very helpful in reducing the need for insulin.

4. Are there POCT devices for measuring triglycerides at home?
No.

5. What are VLDL and how are they related to triglycerides?
VLDL (very low-density lipoproteins) are a class of lipoproteins. Lipoproteins (HDL, LDL, etc.) are molecular complexes containing proteins, cholesterol, triglycerides and phospholipids in proportions that vary according to the lipoprotein class. VLDL in particular contain mainly triglycerides and proteins. No validated test for measuring serum VLDL is currently available.