My doctor recently ordered a “lipid” test and told me that the LDL was too high and the HDL too low. What is a lipid and what is the difference between LDL and HDL?
A. A lipid is simply any fatty substance in the blood that will not mix with the blood, such as cholesterol and Triglycerides. Just like oil and water don’t mix, cholesterol and Triglycerides won’t dissolve in the blood, unless they are mixed with proteins. Lipids travel in the blood in a package of fat and protein, called lipoproteins. The two major types of lipoproteins are low-density lipoprotein, abbreviated LDL and high-density lipoproteins, abbreviated as HDL. A high level of LDL can signify an increased risk of heart disease, which is why they are often called the “bad cholesterol”. HDL helps to carry cholesterol away from the arteries back to the liver where it is passed from the body. Because of this important function, HDL cholesterol is often called the good cholesterol.
