High Cholesterol Diseases
What is high cholesterol?
High cholesterol is a condition in which you have too many lipids (fats) in your blood. It’s also called hyperlipidemia or hypercholesterolemia.
Your body needs just the right amount of lipids to function. If you have too many lipids, your body can’t use them all. The extra lipids start to build up in your arteries. They combine with other substances in your blood to form plaque (fatty deposits).
This plaque might not cause any problems for years, but over time, the plaque silently gets bigger and bigger within your arteries. This is why untreated high cholesterol is dangerous. Those extra lipids in your blood help make the plaque bigger without you even knowing it. The only way to know you have high cholesterol is through a blood test.
A blood test, called a lipid panel, tells you how many lipids are circulating in your blood. What is considered high cholesterol depends on your age, sex and history of heart disease.
Good cholesterol vs. bad cholesterol
There are several types of lipids. The main ones you’ve probably heard about are “good cholesterol” and “bad cholesterol.”
Good cholesterol is called high-density lipoprotein (HDL). Think of the “H” as meaning “helpful.” Your HDLs carry cholesterol to your liver. Your liver keeps your cholesterol levels balanced. It makes enough cholesterol to support your body’s needs and gets rid of the rest. You must have enough HDLs to carry cholesterol to your liver. If your HDLs are too low, you’ll have too much cholesterol circulating in your blood.
Bad cholesterol is called low-density lipoprotein (LDL). This is the culprit that makes plaque form in your arteries. Having too many LDLs can lead to heart disease over time.
When to get your cholesterol checked
High cholesterol can start in childhood or adolescence. That’s why current guidelines suggest beginning screenings during childhood.
- Children and teens: Get your cholesterol checked every five years starting at age nine. A child whose parents have high cholesterol or a history of heart problems may begin even sooner.
- People assigned male at birth (AMAB): Get your cholesterol checked every five years until age 45. From age 45 to 65, get checked every one to two years. After age 65, get checked every year.
- People assigned female at birth (AFAB): Get checked every five years until age 55. From age 55 to 65, get checked every one to two years. After age 65, get checked every year.
These are general guidelines. Your healthcare provider will discuss what’s best for you. For example, someone in their 20s with high cholesterol numbers may need yearly tests for a while. People with other heart disease risk factors may need more frequent tests, too.
Causes of high cholesterol
Lifestyle factors and genetics both play a role in causing high cholesterol. Lifestyle factors include:
- Smoking and tobacco use: Smoking lowers your “good cholesterol” (HDL) and raises your “bad cholesterol” (LDL).
- Being under a lot of stress: Stress triggers hormonal changes that cause your body to produce cholesterol.
- Drinking alcohol: Too much alcohol in your body can raise your total cholesterol.
- Not moving around enough: Physical activity like aerobic exercise improves your cholesterol numbers. If you have a desk job or sit a lot in your free time, your body won’t produce enough “good cholesterol.”
- Diet: Some foods may raise or lower your cholesterol. Sometimes healthcare providers will recommend dietary changes or a visit with a nutritionist to discuss your diet.
Symptoms of high cholesterol
High cholesterol doesn’t cause any symptoms for most people. You could be a marathon runner and have high cholesterol. You won’t start to feel any symptoms until the high cholesterol causes other problems in your body.
High cholesterol raises your risk of conditions like peripheral artery disease, high blood pressure and stroke. High cholesterol is common among people with diabetes.
How does high cholesterol affect my body?
Over time, high cholesterol leads to plaque buildup inside your blood vessels. This plaque buildup is called atherosclerosis. People with atherosclerosis face a higher risk of many different medical conditions. That’s because your blood vessels do important work all throughout your body. So when there’s a problem in one of your blood vessels, there’s a ripple effect.
You can think of your blood vessels as a complex network of pipes that keep blood flowing through your body. Plaque is like the gunk that clogs your pipes at home and slows down your shower drain. Plaque sticks to the inner walls of your blood vessels and limits how much blood can flow through.
When you have high cholesterol, you have plaque forming inside your blood vessels. The longer you go without treatment, the bigger the plaque gets. As the plaque gets bigger, your blood vessels become narrowed or blocked. Like a partly clogged drain, your blood vessels may still work for a long time. But they won’t work as efficiently as they should.
High cholesterol raises your risk of other medical conditions depending on which blood vessels are clogged.
Coronary artery disease (CAD)
Coronary artery disease (CAD) is also called coronary heart disease (CHD) or ischemic heart disease. This is what most people mean when they use the term “heart disease.” CAD is the most common form of heart disease in the U.S. and the leading cause of death.
CAD happens when atherosclerosis affects your coronary arteries. These are the blood vessels that carry blood to your heart. When your heart doesn’t get enough blood, it gets weaker and stops working as it should. CAD can lead to a heart attack or heart failure.
What many people don’t know is that CAD can affect younger people. In fact, about 1 in 5 people who die from CAD are under age 65. That’s why it’s important to get your cholesterol checked starting at a young age. Over time, plaque can silently build up in your coronary arteries. Many people don’t realize it’s happening until they get chest pain (angina) or another sign of a heart attack.
Carotid artery disease
When atherosclerosis affects your carotid arteries, it’s called carotid artery disease. Your carotid arteries carry blood to the large, front part of your brain. When plaque narrows these arteries, your brain can’t get enough oxygen-rich blood.
Carotid artery disease can lead to a transient ischemic attack (TIA or “mini-stroke”) or a stroke.
Peripheral artery disease (PAD)
When atherosclerosis affects the arteries in your legs or arms, it’s called peripheral artery disease (PAD). The arteries in your legs and arms are “peripheral” because they’re away from your heart and the center of your body. PAD is more common in your legs but can also happen in your arms.
PAD is dangerous because it often causes no symptoms. You might finally start to feel symptoms when a peripheral artery is at least 60% blocked. A key symptom is intermittent claudication. This is a leg cramp that starts up when you’re moving around but then stops when you rest. It’s a sign of reduced blood flow caused by the growing plaque in your artery.
PAD can cause major problems in your legs and feet but also elsewhere in your body. That’s because all your blood vessels are connected through your cardiovascular system. So, plaque buildup in one area slows down your whole network of “pipes.”
PAD isn’t the same as coronary artery disease (CAD), but the two conditions are related. People with one condition are likely to have the other one, too. Both PAD and CAD have many of the same risk factors.
High blood pressure
High blood pressure (hypertension) and high cholesterol are linked. Cholesterol plaque and calcium cause your arteries to become hard and narrow. So, your heart has to strain much harder to pump blood through them. As a result, your blood pressure becomes too high.
High blood pressure and high cholesterol are two of the biggest causes of heart disease. In the U.S., about 1 in 3 adults have high blood pressure, and about 1 in 3 adults have high cholesterol. For more than half of the adults in each group, treatment isn’t helping enough or else they’re not using any treatment.
Medications from your healthcare provider can help a lot, but lifestyle changes can help those medications work at their best. Lifestyle changes are important for managing both high cholesterol and high blood pressure. Some changes include:
- Eat less saturated fat and trans fat: Fast food can contain high amounts of both. But even foods at formal restaurants can be high in saturated fat depending on how they’re cooked.
- Eat fewer fried foods and processed foods: These include prepackaged desserts and snacks.
- Eat less sodium (salt): Some foods have hidden salt. It’s important to read labels in the store. Some restaurants may be able to share nutrition information for menu items.
- Stop smoking and using tobacco products: Smoking is a leading risk factor for heart disease and blood vessel problems.
What medical problems affect my cholesterol levels?
Medical problems and cholesterol have a two-way relationship. High cholesterol can cause medical problems like atherosclerosis. But some medical conditions can also put you at a higher risk of having high cholesterol. Here are some conditions that may affect your cholesterol levels.
Chronic kidney disease (CKD)
People with chronic kidney disease (CKD) face a higher risk of developing coronary artery disease. That’s because CKD causes plaque to build up more quickly in their arteries. People with early-stage CKD are more likely to die from heart disease than kidney disease.
CKD causes you to have more triglycerides (a type of fat) in your blood. It also causes you to have more very low-density lipoprotein (VLDL) cholesterol. VLDLs are particles that carry triglycerides. Meanwhile, CKD lowers your “good cholesterol” (HDL) levels and prevents your HDLs from working as they should. CKD also changes the structure of your “bad cholesterol” (LDL) particles so they cause more harm.
People with HIV are nearly twice as likely as people without HIV to have a heart attack or stroke. Researchers used to think this higher risk came from HIV medications (antiretroviral therapy). They believed those medications raised a person’s cholesterol. But newer research shows the culprit is actually a person’s immune system.
Even if your HIV is managed, your immune system may still be activated. This puts your body in a state of chronic inflammation. This inflammation triggers plaque buildup and atherosclerosis.
The good news is that people with HIV are living longer. But that means more research needs to explore how chronic diseases like heart disease affect them.
Having thyroid disease can affect your cholesterol levels. That’s because the thyroid hormone influences how your body processes lipids (fats). The impact depends on what kind of thyroid disease you have.
- Hyperthyroidism: This condition causes your body to make too much thyroid hormone. Medications used to treat this condition can raise your cholesterol levels (total, LDL, and HDL). If you’re being treated for hyperthyroidism, talk with your healthcare provider about how to manage your cholesterol.
- Hypothyroidism: This condition causes your body to make too little thyroid hormone. It also causes you to have higher cholesterol levels. In this case, treatment for thyroid disease lowers your cholesterol levels. But you may still need to take statins to get your cholesterol in the ideal range. Your provider will discuss what’s best for your individual case.
Researchers continue to explore the links between thyroid disease and heart disease. Some studies show that thyroid disease can cause heart problems unrelated to cholesterol or plaque buildup. For example, both hyperthyroidism and hypothyroidism may raise a person’s risk of heart failure.
People with lupus usually have higher levels of “bad cholesterol” (LDL, VLDL) and triglycerides. They also have lower levels of “good cholesterol” (HDL). People who have active lupus face a greater risk of high cholesterol compared with those who have well-managed (quiet) lupus.
Lupus raises your risk of developing coronary artery disease. That’s because lupus causes your body to be in a state of chronic inflammation. This inflammation leads to faster plaque buildup in your arteries.
Polycystic ovary syndrome (PCOS)
People with polycystic ovary syndrome (PCOS) face a higher risk of heart disease. This risk goes up more as they age. PCOS raises the risk of many heart disease risk factors, including diabetes and high blood pressure. People with PCOS are more likely to have high “bad cholesterol” (LDL) levels and low “good cholesterol” (HDL) levels.
Diabetes mellitus (Type 1 diabetes and Type 2 diabetes) doubles your risk for coronary artery disease and peripheral artery disease. Diabetes is linked with lower levels of HDLs and higher levels of triglycerides and LDLs.
About 7 out of 10 people with Type 2 diabetes are diagnosed with diabetes-related dyslipidemia. This means they have high triglyceride levels, high “small dense” LDL levels, and low HDL levels. “Small dense” LDL is a specific type of cholesterol protein that can easily enter your artery wall and cause damage. Having too many small dense LDLs in your blood can cause plaque to grow.
Researchers continue to explore how diabetes and heart disease relate to each other.
How can I lower my cholesterol?
Talk with your healthcare provider about the best way to lower your cholesterol. Some people only need some simple lifestyle changes like eating less saturated fat. Others need lifestyle changes plus medication. People with medical conditions that affect their cholesterol may need a more complex approach. Talk with your provider about your medical history, family history and lifestyle factors. Together, you’ll come up with a plan for lowering your cholesterol numbers.
Remember that even the best plans take time to work. And we all have setbacks. It’s OK to struggle, and it’s also OK to tell your provider when a plan isn’t working. Sometimes even the strictest lifestyle changes don’t lower your cholesterol numbers enough. That’s because most of your body’s cholesterol is produced by your liver. So, many other factors come into play that are out of your control and have nothing to do with what’s on your dinner plate.
Take things one step at a time, and remember that having high cholesterol isn’t a personal failure. It’s a result of many small changes quietly happening inside your body. Take control of what you can, but know that medications and other medical interventions are there to fill in the gaps.
A note from Cleveland Clinic
High cholesterol is sneaky and silent. You could have too many lipids in your blood and not know it for many years. A simple blood test is the only way to find out. High cholesterol affects people of all ages, including those who are active and feel healthy. Some medical conditions raise a person’s risk of high cholesterol and heart disease. Learn your numbers and talk with your provider about what they mean for you.
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