Eighty-six million American adults have high cholesterol levels, but one-third of Americans say they haven’t had their cholesterol levels checked in the past five years.
Testing and managing your cholesterol is very important to prevent heart disease and other serious health problems. But figuring out when to test and what to make of the numbers can be daunting.
How harmful is “bad cholesterol” to health? Should I be concerned if my total cholesterol is too high? And how much can I lower my levels by changing my diet and exercise habits?
We asked experts what you need to know about cholesterol testing and management.
What is cholesterol?
Cholesterol is a fatty substance (also called a lipid) produced by the liver. It is essential for making cell membranes and hormones. Normally, the liver produces all the cholesterol you need. However, some foods, such as meat and dairy products, can increase circulating cholesterol, so you may be asked to fast before your cholesterol test.
Cholesterol gets a bad rap because there is strong evidence linking high cholesterol levels to plaque buildup in arteries and hardening of blood vessel walls over time. In medical terms, this is called atherosclerosis. Eventually, the buildup can block blood flow to the heart and cause a heart attack. Plaque fragments can also rupture and travel to other parts of the body, causing a stroke.
Most people have no symptoms until their arteries are already severely clogged. That’s why doctors look to cholesterol levels to detect and treat cardiovascular disease early, said Dr. John Wilkins, associate professor of cardiology and epidemiology at Northwestern University Feinberg School of Medicine.
When is a cholesterol test needed?
According to the American Heart Association, all adults age 20 and older should have a cholesterol test every four to six years. If you have certain risk factors, such as high blood pressure, diabetes, or a family history of heart disease, you may need more frequent testing.
However, heart disease is becoming increasingly prevalent among young people. The National Heart, Lung, and Blood Institute recommends starting cholesterol testing between ages 9 and 11, or as young as 2 years if there is a strong family history of high cholesterol and heart disease. Your doctor can help you decide when to get tested.
What does a cholesterol test show?
Your doctor can check your cholesterol through a blood test called a lipid panel or lipoprotein profile. This measures total cholesterol. Low-density lipoprotein, or LDL cholesterol. High-density lipoprotein (HDL) cholesterol. Triglycerides are another type of fat that hardens arteries and are primarily obtained from food. All of these are reported in milligrams per deciliter.
Tests may include very low density lipoproteins (VLDL), which carry triglycerides to different parts of the body.
For some people, your doctor may order a test for apolipoprotein B (ApoB). Apolipoprotein B (ApoB) is the particle that actually carries cholesterol in the blood. According to Dr. Stephen Kopecky, a preventive cardiologist at the Mayo Clinic in Rochester, Minn., this may be a better predictor of heart attack risk, especially if LDL numbers are moderately or slightly elevated. It is said that
There are several home tests that use a finger prick blood sample to check cholesterol. If you use any of these tests, you should still discuss your results with your doctor and, if possible, take an in-person test, which is considered more reliable.
What is a normal cholesterol level?
What is “normal” depends on several factors. Cholesterol levels generally increase with age. Men tend to have higher levels throughout their lives, while women typically experience increased levels during pregnancy or menopause. Certain genes can also influence the amount of cholesterol produced in the body.
Perhaps the most important number to track is LDL, which is considered the “bad cholesterol” that builds up in the walls of your arteries. For most people, LDL should be less than 100 mg/dL. The lower the better.
Dr. Douglas Jacoby, medical director of Penn’s Center for Preventive Cardiology and Lipid Management, says people with diabetes, pre-existing plaque buildup, or other factors that put them at risk for heart disease should try to keep their LDL below 70. He said it may be necessary to keep it.
High triglyceride levels are also associated with an increased risk of heart disease. Ideally, these levels should stay below 150 mg/dL.
HDL, also known as “good cholesterol,” scavenges excess cholesterol from the arteries and returns it to the liver for removal from the body. This is why higher HDL levels are generally considered better. Aim to keep your HDL above 40 mg/dL, with 60 or above considered optimal.
However, some studies suggest that when HDL exceeds 80 mg/dL in men and 100 mg/dL in women, it may lose its protective function and instead promote atherosclerosis. It has been.
If your LDL or triglyceride levels fall into the “borderline high” category, it can be difficult to assess your risk of heart disease. In these cases, your doctor may review additional calculations included in the test report, such as total cholesterol, which is calculated by adding 20% of your HDL, LDL, and triglyceride values.
A more useful measure may be non-HDL numbers, which show how much of your total cholesterol is made up of LDL and other artery-clogging particles. This number does not include triglycerides, so it may reflect your cholesterol more accurately when you’re eating normally than when you fast for a blood test.
Your doctor can also check your cholesterol ratio, which is total cholesterol divided by HDL. The higher this ratio, the higher the risk of heart disease.
What can I do to lower my cholesterol?
Eating more soluble fiber, such as legumes, whole grains, seeds, fruits, and vegetables, binds to cholesterol in your digestive tract and helps remove it from your body. Some foods, such as nuts, avocados, and fatty fish, also contain polyunsaturated fats, which lower LDL cholesterol in the blood.
Limit foods high in saturated fat, trans fat, and cholesterol, such as red meat, butter, and cheese, and instead choose plant-based proteins such as soy and minimally processed foods.
Although the effects of these dietary choices on cholesterol vary from person to person, Dr. Kopecky says dietary changes can “lower your risk of heart attack, stroke, or death within three months.”
According to Dr. Kopecky, exercising several days a week can further lower LDL and triglyceride levels and increase HDL cholesterol. And these lifestyle changes can also greatly benefit people who need cholesterol-lowering drugs.
What about medicine?
If you have already had a heart attack or stroke, or if an ultrasound or angiogram shows a significant blockage in your arteries, your doctor may recommend drugs to lower your cholesterol. If your LDL cholesterol is 190 or higher, your health care provider may consider medication.
For most other people, Dr. Wilkins says, doctors consider cholesterol levels in conjunction with factors such as age, family history of heart disease, and smoking history before deciding whether to prescribe drugs.
The most commonly prescribed cholesterol drugs are statins, which lower LDL cholesterol. Finding the right drug and dose can take trial and error, and most people will need to take statins for the rest of their lives, Dr. Wilkins added. If you stop taking the drug, your cholesterol levels may rise and your risk of developing heart disease may be reversed.
“No one is at zero risk,” he says. “But there are many things you can do to alleviate it.”
