What Cholesterol is and Cholesterol Tests

Cholesterol, LDL, and HDL: What are They?


Cholesterol has many functions. Some of the major functions include synthesizing Vitamin D, bile acids, and steroid hormones. Cholesterol is also abundant in cell membranes, and plays a big roll in the nervous system that enables learning and memories.


HDL and LDL stand for High Density Lipoproteins and Low Density Lipoproteins. LDL is twice the size as HDL particles. LDL has a lower density because they have a much higher amount of fat in their core. One function LDL does is that it transports cholesterol throughout the body. HDL are complex chemicals that contain a core globule of fat that is surrounded by proteins. It is the smallest of all the lipoproteins. It has a relatively low amount of fat compared to its protein content. HDL binds with the excess cholesterol in the walls of your arteries and takes it to the liver to be removed from your body through the intestines.

Cholesterol Testing and Other Types of Molecules Tested

Doctors monitor the concentration of HDL and LDL in a patients blood to better determine whether a person is at risk for cardiovascular disease. LDL is the main source of artery-clogging plague and HDL works to clear cholesterol from the blood stream. That is why they check those two concentrations. Along with HDL and LDL, doctors also monitor Triglycerides and Total Cholesterol in a patients blood.

Cholesterol Testing

Cholesterol testing can help your doctor use these numbers to predict a patients lifetime or 10 year risk for a heart attack or stroke. LDL reading 190 mg/DL and above represents a high risk for Heart Disease and is a strong indicator that the individual can benefit fro treatment to reduce the risk. HDL levels less than 40 mg/DL are at high risk as well. Triglyceride levels 150 and above are borderline to very high risk of Heart Disease.

How to change Cholesterol Levels

  • Eat a healthy diet
  • Maintain a healthy weight
  • Exercise regularly
  • Do not smoke
  • Treat high cholesterol with medications and/or lifestyle changes

Saturated, Unsaturated, and Trans Fats & Cholesterol Levels

All of these types of fats can raise blood cholesterol. By not eating as much of these types of fats, it can lower a person's cholesterol levels. By eating too much of these fats, it can increase a person's chances of heart disease along with an increase in cholesterol levels.