What is LDL cholesterol?
Low-density lipoprotein (LDL) is a lipoprotein containing Apo B that carries cholesterol in the blood. Maintaining and monitoring healthy blood fats is important for good health. Dietary and lifestyle factors, as well as other health conditions, can affect the level of cholesterol in the blood.
The LDL test is a calculated value that is usually ordered as part of a full lipid profile on either a routine health exam or to evaluate risk factors for heart disease.
The LDL test is usually done as part of a larger lipid panel that includes at least total cholesterol, LDL or non-HDL cholesterol, and triglycerides.
Why test LDL cholesterol?
Unless this is ordered as a retest or for a specific reason, we recommend ordering this as part of a health test.
Health Check
Discover your risk factors for lifestyle diseases in time to do something about them.
Monitoring
Monitor changes to your blood values as you make lifestyle changes or undergo treatments.
What causes low LDL cholesterol
Low cholesterol means that you have higher-than-expected cholesterol levels in the blood. Oxidative stress, malnutrition, hyperthyroidism, autoimmune processes, and liver/biliary dysfunction are some causes of low cholesterol.
What causes high LDL cholesterol?
High cholesterol means that you have higher than expected cholesterol levels in the blood. Genetic factors, smoking, dietary saturated fats (especially palmitic acid from butter and trans fats), and a low fibre or low-sodium diet) can all increase your LDL cholesterol. Health conditions like hypothyroidism and insulin resistance can also have this effect.
More information
LDL is often called the ‘bad’ cholesterol because it contributes to heart disease risk, but this description is a misnomer. Cholesterol is cholesterol, LDLs are just the most common circulating Apo B containing lipoproteins which can be retained in your artery wall.
Both naturally randomized genetic studies and randomized intervention trials consistently demonstrate that lower plasma LDL particle concentration reduces the risk of heart disease. The more of these Apo B-containing lipoproteins, such as LDL, that are circulating in your blood, the higher your risk of heart disease [1].
LDL cholesterol rises in pregnancy. Some medications affect LDL-C levels. Tell us if you are taking any medications or supplements.
Instructions
Postpone this test if you are ill. Wait at least 6 weeks after illness to have LDL measured.
The day before
Do not eat or drink anything except water for at least 10 (preferably 12) hours before taking this test.
On the day
This test is ideally done in the early morning after an overnight fast. Remember to take I.D. with you when going to take a test. [2]