Cholesterol is a waxy, fat-like substance that is found in all cells of the body. Your body needs some cholesterol to make hormones, vitamin D, and substances that help you digest foods. Your body makes all the cholesterol it needs. However, cholesterol also comes from the foods you eat.
When you have too much cholesterol in your blood, it can start to build up on the walls of your arteries. This is called atherosclerosis or hardening of the arteries. It can lead to heart disease, strokes, and other problems.
What are healthy cholesterol levels?
When you get a cholesterol test, you’ll receive results for your:
- Total cholesterol
- LDL cholesterol
- HDL cholesterol
- Triglycerides
Here are typical target cholesterol levels for adults:
| Type of Cholesterol | Healthy Level |
|---|---|
| Total cholesterol | Less than 200 mg/dL |
| LDL cholesterol | Less than 100 mg/dL |
| HDL cholesterol | 60 mg/dL or higher |
| Triglycerides | Less than 150 mg/dL |
However, optimal cholesterol levels may vary depending on your risk of heart disease. Your doctor can help determine your target cholesterol ranges.
What is considered dangerously high cholesterol?
Dangerously high cholesterol levels vary based on your specific cholesterol numbers and heart disease risk factors. But in general:
- Total cholesterol above 240 mg/dL is considered high.
- LDL cholesterol above 160 mg/dL is very high and concerning.
- HDL cholesterol below 40 mg/dL is considered too low.
- Triglycerides above 200 mg/dL are considered high.
Your doctor may want your total and LDL cholesterol to be even lower than these levels if you already have heart disease, diabetes, or other risk factors.
Total cholesterol
Your total cholesterol level is the combination of LDL, HDL, and 20 percent of your triglycerides. Total cholesterol above 240 mg/dL is considered high risk.
LDL cholesterol
LDL cholesterol is considered the “bad” kind because it can build up on artery walls and increase your risk for heart attack and stroke. LDL cholesterol above 160 mg/dL is considered very high and dangerous.
HDL cholesterol
HDL cholesterol has protective benefits and is considered the “good” kind. It helps remove LDL cholesterol from your arteries. HDL cholesterol below 40 mg/dL for men and 50 mg/dL for women is considered too low.
Triglycerides
Triglycerides store unused calories and provide your body with energy. But high levels make plaque buildup more likely. Triglycerides above 200 mg/dL are considered elevated.
What are the symptoms of high cholesterol?
High cholesterol usually has no signs or symptoms. You may feel perfectly fine. This is why getting your cholesterol checked is important.
Sometimes very high cholesterol can cause outward symptoms, including:
- Fatty skin deposits called xanthomas, usually seen on elbows and knees
- Gray or white rings around the corneas of your eyes
- Yellowish fatty plaque deposits on eyelids
- Chest pain or tightness (angina)
But often the first sign that high cholesterol is damaging your arteries may be a heart attack or stroke. Getting early treatment is critical to prevent these complications.
What causes high cholesterol?
A variety of factors can increase your cholesterol levels and heart disease risk:
Diet
Eating saturated fats, trans fats, and cholesterol found in some meats, full-fat dairy, fried foods, baked goods, and processed foods encourages your body to make more cholesterol. Eating too many refined carbs like white bread, cookies, and sugary drinks also raises bad cholesterol.
Weight
Being overweight or obese can lower HDL, raise LDL, and increase triglycerides. Losing weight may help improve cholesterol numbers.
Physical activity
Lack of exercise reduces HDL cholesterol. Being inactive is a major risk factor for high LDL and triglycerides.
Smoking
Cigarette smoke damages your arteries. It also lowers HDL cholesterol while increasing your risk of dangerous clots.
Genetics
Some people inherit genes from their mother, father, or even grandparents that cause high cholesterol. Genes can predispose you to high total and LDL cholesterol.
Medical conditions
Some health conditions and medications can negatively impact cholesterol levels. These include:
- Type 2 diabetes
- Kidney disease
- Pregnancy and birth control pills
- Hypothyroidism
- Polycystic ovary syndrome (PCOS)
- Chronic conditions causing inflammation
Age and gender
Cholesterol levels rise as you age. Before menopause, women often have lower total cholesterol than men. After menopause, women’s LDL levels often increase.
Who is at risk of high cholesterol?
Anyone can have high cholesterol, but certain individuals have an increased risk including:
- People with a family history of high cholesterol
- Anyone who is overweight or obese
- People who eat a poor diet high in saturated and trans fats
- Individuals who don’t exercise
- Cigarette smokers
- People with diabetes, hypothyroidism, or other conditions that impact cholesterol
- The elderly
- Men aged 45 years and older
- Women aged 55 years and older
- People with existing heart disease
- Individuals who’ve had a heart attack or stroke
- People with carotid artery disease or peripheral artery disease (PAD)
High cholesterol typically has no signs and can go undetected without testing. Talk to your doctor about whether cholesterol screening is recommended for you.
Complications of dangerously high cholesterol
Over time, elevated LDL cholesterol can quietly damage your arteries. This can ultimately lead to serious, even fatal, complications including:
Heart attack
If an area of plaque ruptures in a coronary artery, a blood clot may form and block blood flow to part of your heart muscle. This can lead to chest pain and heart damage or heart attack.
Stroke
Plaque can build up in the arteries supplying blood to your brain. A disruption in blood flow to the brain is a stroke. This can lead to permanent disability or death.
Peripheral artery disease (PAD)
Cholesterol plaque in the arteries of the legs can cause PAD. This usually causes cramping or tiredness in the calf or buttocks during activity like walking. It also increases the risk of poor wound healing and gangrene.
Carotid artery disease
Plaque can narrow the arteries in your neck that supply oxygen to your brain. This raises your risk of stroke.
How is high cholesterol diagnosed?
A cholesterol test, also called a lipoprotein panel or lipid profile, is done to measure:
- Total cholesterol
- LDL cholesterol
- HDL cholesterol
- Triglycerides
This blood test is done after a 9- to 12-hour fast. The standard recommendations for cholesterol screening are:
- All adults should have cholesterol screened at least once starting at age 20
- Screening should start at an earlier age if you have heart disease or high risk factors
- Repeat screening every 4 to 6 years for low risk adults
- More frequent repeat testing if you have high cholesterol or heart disease risk factors
Talk to your doctor about your individual cholesterol testing needs. Some doctors also recommend advanced cholesterol testing, such as checking apolipoproteins or LDL particle size. These can provide more accuracy about your risk beyond just the LDL number.
Treating high cholesterol
If you are diagnosed with high cholesterol, treatment will depend on your 10-year risk of developing heart disease or stroke. Treatment options may include:
Heart-healthy lifestyle changes
Your doctor will likely recommend lifestyle changes including:
- Following a heart-healthy diet low in saturated and trans fats
- Exercising for 30 minutes most days of the week
- Reaching and maintaining a healthy weight
- Quitting smoking to boost HDL and lower LDL
- Drinking alcohol in moderation, if at all
Cholesterol-lowering medications
If lifestyle changes aren’t enough, cholesterol-lowering medications may be prescribed. Common options include:
- Statins like atorvastatin (Lipitor) or rosuvastatin (Crestor) – These work by reducing cholesterol production in your liver
- Ezetimibe (Zetia) – This blocks cholesterol absorption from your small intestine
- PCSK9 inhibitors like evolocumab (Repatha) – These lead to more LDL cholesterol being removed from your blood
- Bile acid sequestrants like cholestyramine (Prevalite) – These bind to bile acids containing cholesterol to remove them from your body
- Niacin – This boosts HDL cholesterol while lowering LDL and triglycerides
In some cases, two or more medications may be needed to reach target cholesterol levels.
Preventing high cholesterol
Making healthy lifestyle choices can help prevent high cholesterol in the first place. Try these prevention tips:
- Eat a diet low in saturated fats, trans fats, cholesterol, and refined carbs like sugary foods, white bread, and pastries
- Load up on fruits, vegetables, whole grains, beans, fish, skinless poultry, nonfat dairy, nuts, and vegetable oils
- Limit red meat, full-fat dairy, and fried foods
- Stay active with at least 150 minutes per week of moderate exercise like brisk walking
- Aim for a healthy body weight
- Don’t start smoking and quit if you currently smoke
- Drink alcohol in moderation, if at all
- Take medications as directed if prescribed to treat medical conditions
Getting your cholesterol checked regularly and working with your doctor to address any issues early can also help prevent complications of high cholesterol down the road.
Conclusion
Dangerously high cholesterol levels significantly raise your risk of heart disease and stroke. Total cholesterol above 240 mg/dL, LDL cholesterol above 160 mg/dL, and HDL cholesterol below 40 mg/dL are considered high-risk.
High cholesterol often has no obvious symptoms. Following heart-healthy lifestyle habits, getting regular cholesterol screenings, and promptly treating any abnormalities detected are important to avoid serious complications.