What is it?
Cholesterol is one of the building blocks of the human body. It is an essential component of our cell membranes and is required for the production of many hormones and other molecules. We get cholesterol from the food we eat, and our livers can make it from scratch. But while cholesterol is necessary for life, an excess of cholesterol in the blood (hypercholesterolemia) is strongly linked to deadly cardiovascular disease. Understanding this duality has been one of the most important challenges of modern medicine.
Cholesterol circulates in the bloodstream attached to tiny globules of fat and protein called lipoproteins. A diagnosis of ‘high cholesterol’ usually corresponds to an excess of low-density lipoprotein (LDL or ‘bad cholesterol’) in the blood.
How is high cholesterol harmful?
High levels of LDL and related lipoproteins contribute to a disease called atherosclerosis – the buildup of fatty deposits in the walls of arteries that carry blood to vital organs like the heart and brain. These deposits, known as plaques, can restrict blood flow and, most ominously, can break away from the walls of the arteries and block the blood flow of blood altogether. The result can be a heart attack or stroke.
In contrast, high levels of high-density lipoprotein (HDL or ‘good cholesterol’) are beneficial. HDL particles appear to be able to carry cholesterol away from plaques and back to the liver for processing, thereby reducing the size of the plaques.
What causes high cholesterol, and how common is it?
High cholesterol is most often caused by unhealthy lifestyle choices. The main culprits are physical inactivity, poor diets, and smoking. Other factors may be beyond your control. For example, LDL levels tend to increase in women after menopause due to hormonal changes. You may also have a genetic predisposition to produce too much cholesterol in your liver, or to metabolize excess cholesterol too slowly.
According to the Centers for Disease Control and Prevention, roughly one of every six U.S. adults has dangerously high cholesterol, and the incidence tends to increase in frequency as we age. Most cases are detected in men over age 45 and women over age 55, but thanks to the unhealthy diets and exercise habits of many Americans, we are finding more and more cases of high cholesterol in younger individuals too.
What are the symptoms?
Unfortunately, high cholesterol usually has no symptoms at all until it’s too late. The best way to find out whether you have high cholesterol is to have a blood test.
Should I be tested? How does the test work?
Men should have their first cholesterol test no later than age 35, and women no later than age 40. If you have a family history of high cholesterol, you might need to be tested at a younger age. And if you already know that you have high cholesterol, you should have your numbers rechecked annually or more frequently, depending on your treatment plan.
When we test your cholesterol, we usually do it as part of a ‘lipid panel’ that measures your total cholesterol, your LDL and HDL, a third lipoprotein called VLDL (very low density lipoprotein), and a closely related lipid called triglyceride. We obtain the test sample after you have been fasting for 12 hours.
In general, we want to see your total cholesterol, LDL and triglycerides as low as possible, and your HDL as high as possible. Your exact numerical goals depend on many factors, and your primary care provider will help you determine whether your results are acceptable for your unique situation.
How do you treat high cholesterol?
For most people, the best treatment for high cholesterol is lifestyle modification, which is rarely easy. It requires hard work and dedication, but the benefits can be enormous. Regular coaching from your primary care provider can help a lot. The basics of a heart-healthy lifestyle include the following:
- Losing extra pounds and maintaining a healthy weight
- Getting at least 20 minutes of heart-pounding exercise three times a week
- Eating lots of vegetables, fruits and whole grains
- Avoiding “trans-” or “partially hydrogenated” fats
- Avoiding extra sodium
- Cutting back on alcohol consumption
- Quitting smoking
Sometimes lifestyle modification isn’t enough, or proves too difficult to maintain. In those cases, medication might be necessary. The most commonly-used medications are statins, which can be highly effective in lowering LDL levels. Your primary care provider will help you determine whether you need a statin and, if so, will help you use it safely and appropriately.
Over-the-counter supplements (like niacin and omega-3 fatty acids) and specific foods (like artichokes, barley and oat bran) might also be helpful, but you should discuss these options with your provider first.
Can high cholesterol be prevented?
Very often the answer is yes. Unless you have a strong genetic predisposition toward high cholesterol, the same heart-healthy lifestyle described above can keep your lipid levels in safe ranges.