Cholesterol: Know the Facts
By Robert St. Amant, MD | Clinical Lipidology
on February 3, 2014
Cholesterol is actually an important part of your health as it helps the body build vital hormones, bile acids, vitamin D, and cell walls. Most of the cholesterol is produced in your body and only a small portion is absorbed from your diet. Your cholesterol level is dependent upon a combination of production, absorption, and elimination from the body. Triglycerides are a source of energy, but like cholesterol, they can also contribute to the process of atherosclerosis.
It is most important to understand that both cholesterol and triglycerides are lipids---fatty substances that by their nature cannot dissolve in the blood. Therefore, the body creates lipid trafficking particles called lipoproteins. The cholesterol and triglyceride molecules are carried as passengers in the center of these lipoproteins. The outer surface contains the protein that allows these particles to be dissolved in the blood and transported throughout the body.
There are no "bad" or "good" cholesterol molecules. It is actually the specific type of protein on the outer surface of the lipoprotein particle that determines if the cholesterol inside is "bad" or "good". The ApoB protein defines the "bad" LDL cholesterol particle that can enter the wall of the arteries. The ApoA-1 protein defines the "good" HDL cholesterol particle which helps keep your arteries clean.
Cholesterol can only enter the walls of your arteries by way of the bad ApoB lipoprotein particles thereby leading to heart attacks, strokes, and peripheral artery disease. So in many cases, the more accurate measure of the risk of your cholesterol causing atherosclerosis--" hardening of the arteries"---is the actual number of the bad LDL ApoB lipoprotein particles in your blood more so than your LDL cholesterol concentration found on the standard lipid panel test.
In some cases, the LDL cholesterol value on your lipid panel is consistent with the number of your LDL particles and does reflect your true risk. But in many cases, especially if you have insulin resistance, prediabetes, metabolic syndrome, or Type 2 Diabetes, the LDL particle number far exceeds your lipid panel's LDL cholesterol concentration. In these situations the LDL cholesterol level on the lipid panel significantly underestimates your true risk and more advanced testing is indicated to determine appropriate treatment recommendations for therapeutic lifestyle changes and/or medication.
Genetics is certainly a contributor to atherosclerosis. Therefore, your family history can be a very important risk factor for heart attack and stroke. If you have a relative, especially parent or sibling, who's had a heart attack, stent, coronary artery bypass, angina or stroke in their 60s or younger, then your cardiovascular risk goes up significantly.
Another important contributor to atherosclerosis is inflammation. Factors that contribute to inflammation include smoking, insulin resistance, high blood pressure, poor diet, excess fat around the waist line, and inadequate regular physical activity. Everyone should have their lipids checked by 20 years of age and regularly thereafter. As you grow older, your risk increases and your lipid and glucose levels can increase. See your physician soon for an evaluation of your cardiovascular risk factors and appropriate laboratory testing.
For more information about the Lipid services available at Baton Rouge General or to schedule a consultation or appointment, please call (225) 819-1161 or click here.