High Cholesterol: Causes, Symptoms, Diagnosis, Treatment, and Prevention
Among the leading causes of death worldwide, heart disease and stroke are both caused by high cholesterol levels in your body. Cholesterol helps your body make hormones, vitamin D, and bile acids that help you digest food. A high level of cholesterol, however, can increase your risk of developing heart disease or stroke, which are among the leading causes of death in the world.
What Causes High Cholesterol?
There are many factors that can contribute to high cholesterol levels, some of which are within your control and some of which are not. Some of the common causes of high cholesterol are:
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You can raise your blood cholesterol levels by eating foods high in saturated fat, trans fat, cholesterol, or refined carbohydrates. These foods include red meat, butter, cheese, pastries, fried foods, and processed foods.
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Sedentary lifestyles and not getting enough exercise can lower HDL (good) cholesterol and raise LDL (bad) cholesterol and triglycerides (another type of fat in the blood).
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Overweight or obesity can increase your blood cholesterol levels, especially if you have a large waist circumference (over 40 inches for men and 35 inches for women).
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Smoking damages the walls of your blood vessels, making them more prone to accumulating cholesterol and other substances. Smoking can also decrease your HDL cholesterol and increase your triglycerides.
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About 1 in 250 people have familial hypercholesterolemia, a condition caused by inherited genes that make them produce more cholesterol or prevent them from removing excess cholesterol from their blood.
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As you get older, your cholesterol levels tend to rise. Women tend to have lower cholesterol levels before menopause, but after menopause, their LDL cholesterol and triglycerides tend to rise.
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Some medical conditions can affect your cholesterol levels, such as diabetes, hypothyroidism, kidney disease, liver disease, or certain medications.
What Are the Symptoms of High Cholesterol?
As a result of high cholesterol, there are no specific symptoms associated with it. As a result of high cholesterol, plaque builds up in your arteries, causing a condition called atherosclerosis. Blood flow to your heart, brain, and other organs can be narrowed or blocked, resulting in serious problems such as:
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Angina (chest pain or discomfort due to reduced blood flow to the heart)
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Heart attack (damage or death of part of the heart muscle due to a blocked artery)
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Stroke (damage or death of part of the brain due to a blocked artery)
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Peripheral artery disease (reduced blood flow to the limbs due to narrowed arteries)
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Aneurysm (a bulge or rupture in an artery wall that can cause internal bleeding)
How Is High Cholesterol Diagnosed?
Lipid panels are the only way to determine if you have high cholesterol. They measure the levels of cholesterol and triglycerides in your blood. In most cases, the results are expressed as millimoles per liter (mmol/L) or milligrams per deciliter (mg/dL).
It is recommended that adults over the age of 20 have their cholesterol checked every four to six years by the American Heart Association (AHA). You may need to have more frequent tests, however, if you have a history of heart disease or stroke, smoking, diabetes, high blood pressure, or obesity.
The AHA also provides the following guidelines for desirable cholesterol levels for adults:
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Total cholesterol: Less than 200 mg/dL (5.2 mmol/L)
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LDL cholesterol: Less than 100 mg/dL (2.6 mmol/L)
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HDL cholesterol: 60 mg/dL (1.6 mmol/L) or higher
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Triglycerides: Less than 150 mg/dL (1.7 mmol/L)
Your doctor will help you interpret your cholesterol test results and determine your optimal cholesterol goal based on your age, gender, and overall health.
How Is High Cholesterol Treated?
By lowering LDL cholesterol and triglycerides and increasing HDL cholesterol, you can prevent or slow down the progression of atherosclerosis and reduce your risk of heart disease and stroke.
The treatment for high cholesterol usually involves a combination of lifestyle changes and medications.
Lifestyle changes include:
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Eating a healthy diet that is low in saturated fat, trans fat, cholesterol, and refined carbohydrates and high in unsaturated fat, fiber, fruits, vegetables, whole grains, nuts, seeds, and fish.
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Getting regular physical activity for at least 150 minutes per week of moderate-intensity aerobic exercise or 75 minutes per week of vigorous-intensity aerobic exercise.
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Losing weight if you are overweight or obese and maintaining a healthy weight.
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Quitting smoking if you smoke and avoiding exposure to secondhand smoke.
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Limiting alcohol intake to no more than one drink per day for women and two drinks per day for men.
Medications include:
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Statins, such as atorvastatin, rosuvastatin, simvastatin, or pravastatin. These drugs work by blocking an enzyme in the liver that produces cholesterol. They can lower your LDL cholesterol by 20 to 60 percent and also slightly increase your HDL cholesterol and lower your triglycerides.
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Bile acid sequestrants, such as cholestyramine, colestipol, or colesevelam. These drugs work by binding to bile acids in the intestine and preventing them from being reabsorbed into the bloodstream. This reduces the amount of cholesterol that the liver can use to make more bile acids, which lowers your LDL cholesterol by 15 to 30 percent.
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Cholesterol absorption inhibitors, such as ezetimibe. This drug works by blocking the absorption of cholesterol from the food you eat in the small intestine. It can lower your LDL cholesterol by 15 to 20 percent and also slightly lower your triglycerides and increase your HDL cholesterol.
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Fibric acid derivatives, such as gemfibrozil or fenofibrate. These drugs work by reducing the production of triglycerides and increasing the breakdown of triglycerides in the blood. They can lower your triglycerides by 20 to 50 percent and also slightly lower your LDL cholesterol and increase your HDL cholesterol.
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Niacin, also known as nicotinic acid or vitamin B3. This drug works by inhibiting the production of LDL cholesterol and triglycerides in the liver and increasing the removal of LDL cholesterol from the blood. It can lower your LDL cholesterol by 5 to 25 percent, lower your triglycerides by 20 to 50 percent, and increase your HDL cholesterol by 15 to 35 percent.
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Injectable medications, such as alirocumab or evolocumab. These drugs work by blocking a protein called PCSK9 that prevents the liver from removing LDL cholesterol from the blood. They can lower your LDL cholesterol by 50 to 60 percent and also slightly lower your triglycerides and increase your HDL cholesterol.
You may need to take more than one medication to achieve your cholesterol goals, based on your cholesterol levels, risk factors, medical history, and potential side effects. Your doctor will prescribe the most appropriate medication based on your cholesterol levels, risk factors, medical history, and possible side effects. Taking these medications will also require regular blood tests to monitor your cholesterol levels and liver function.
How Can You Prevent High Cholesterol?
Maintaining a healthy lifestyle that includes a balanced diet, regular exercise, weight management, quitting smoking, and moderate alcohol consumption is the best way to prevent high cholesterol. You can maintain normal cholesterol levels by adopting these habits, and they can also improve your health and well-being in other ways.
As well as regular check-ups with your doctor and cholesterol testing, you may need to start screening earlier or more frequently if you have a family history of high cholesterol.
Making lifestyle changes and taking medication as prescribed can help you achieve your cholesterol goals and improve your quality of life if you have high cholesterol.
