What is cholesterol and why do we care?
Understanding cholesterol can be tricky. It took me a few years to convince my parents that only foods that contain animal products contain cholesterol. However, fatty foods that are cholesterol free can still raise your body’s cholesterol.
So is all cholesterol bad? No, too much cholesterol is bad. And everyone regulates cholesterol differently.
Cholesterol is a waxy fat-like substance that our bodies need to survive. Animals, including humans, make cholesterol because it is used to make steroid hormones, vitamin D and bile acids. It also is needed in the membranes of our cells so that our cells maintain fluidity. It isn’t found in plants. Cholesterol circulates throughout our bodies, but it can’t circulate in blood without a transporter. Lipoproteins such as “HDL” and “LDL” — also known as “good cholesterol” and “bad cholesterol” — are those transporters.
People consider LDL bad because it prefers to deposit its cholesterol into the walls of arteries, which forms plaque (also known as atherosclerosis). It’s the plaque that then clogs our arteries and leads to heart attacks and strokes. HDL cholesterol is thought to take cholesterol from the arteries and from foods and sends it to the liver, which then processes and removes it from the body. So the healthiest people have high HDL cholesterol and low LDL cholesterol and a very low risk of cardiovascular problems.
So how dangerous is having high cholesterol? Well, in the stroke world, it is thought that having high cholesterol can almost double a person’s risk of having a stroke. In patients with high cholesterol, plaque can form in vessels such as the carotid arteries in the neck, and if the vessel becomes narrow enough, the plaque can break away and move up to the brain. Therefore, we recommend that patients get their cholesterol checked regularly to catch high LDL cholesterol early and to take measures to reduce it if it is high.
Typically, your body produces about 75 percent of its cholesterol. The remaining 25 percent is from cholesterol you consume. The moral of the story is that even vegetarians can have high LDL cholesterol, because most of the time having an elevated cholesterol level is hereditary and is due to how one’s body produces cholesterol.
Certainly reducing one’s intake of cholesterol-rich foods will help lower LDL cholesterol. But additional measures such as prescription medication may be necessary. Also, exercise has been shown to increase HDL cholesterol. Reducing saturated and trans fat intake can also reduce cholesterol levels. If you would like to learn more about cholesterol and cardiovascular disease, the American Heart Association has a helpful website with more information and interactive self-assessments.
If you are over 20 years old and have never had your cholesterol checked, please see your primary care physician and get it checked at least once every five years. You should have it checked more often if any of the following fits you: you’re a male older than 45 or a female older than 50; your cholesterol level has already been measured at 200 or more; your HDL cholesterol is 40 or less; or you have other risk factors, such as suffering a heart attack or stroke.
Also remember: you must fast nine to 12 hours before getting your blood drawn for a cholesterol test.
Hormozd Bozorgchami, M.D.
Instructor, Oregon Stroke Center
OHSU Brain Institute
