Cholesterol is a waxy substance that is found in most cells in the body. Some cholesterol is needed for good health, and your body needs some cholesterol to make hormones and vitamin D, for example. Your body makes all the cholesterol it needs. However, cholesterol also is found in some of the foods you eat, and eating too much of these foods can give your body too much cholesterol, which can cause plaque buildup in your blood vessels, and restrict blood flow.
Cholesterol travels through your bloodstream in small packages called lipoproteins. These packages are made of fat (lipid) on the inside and proteins on the outside.
Two kinds of lipoproteins carry cholesterol throughout the body: low-density lipoproteins (LDL) and high-density lipoproteins (HDL). Having healthy levels of both types of lipoproteins is important.
The problem is, people sometimes have too much cholesterol. Compared with people with normal cholesterol, people with high cholesterol have a higher risk of heart attacks, strokes, and other health problems. The higher your cholesterol, the higher the risk of these problems.
Cholesterol levels are checked by blood tests, and doctors look at different types of cholesterol:
- Total cholesterol
- LDL cholesterol – Some people call this the “bad” cholesterol. That’s because having high LDL levels raises your risk of heart attacks, strokes, and other health problems.
- HDL cholesterol – Some people call this the “good” cholesterol. That’s because having high HDL levels lowers your risk of heart attacks, strokes, and other health problems.
- Non-HDL cholesterol – Non-HDL cholesterol is your total cholesterol minus your HDL cholesterol.
- Triglycerides – Triglycerides are not cholesterol. They are a type of fat. But they often get measured when cholesterol is measured. Very high triglycerides also seems to increase the risk of heart attacks and strokes.
What should your numbers be? In general, people who do not already have heart disease should aim for:
- Total cholesterol below 200
- LDL cholesterol below 100 – or much lower, if they are at risk of heart attacks or strokes
- HDL cholesterol above 40 – but the higher the better.
- Non-HDL cholesterol below 160 – or lower, if they are at risk of heart attacks or strokes
- Triglycerides below 150
Having high cholesterol is just one of many things that can increase your risk of heart attacks and strokes. Other factors that increase your risk include:
- Cigarette smoking
- High blood pressure
- Having a family history — a parent, sister, or brother who got heart disease at a young age (younger than 55 for men and younger than 65 for women).
- Being a man (Women are at risk, too, but men have a higher risk.)
- Older age
If you are at high risk of heart attacks and strokes, having high cholesterol is a problem. On the other hand, if you are at low risk, having high cholesterol might not mean much.
Not everyone who has high cholesterol needs medicines. Cholesterol-lowering medicine called a statin would be required if you:
- Already have had a heart attack or stroke
- Have known heart disease
- Have diabetes
- Have a condition called peripheral artery disease, which makes it painful to walk, and happens when the arteries in your legs get clogged with fatty deposits
- Have an abdominal aortic aneurysm, which is a widening of the main artery in the belly
- In some patients who have more than 2 other risk factors and very high LDL. Most people with any of the conditions listed above should take a statin no matter what their cholesterol level is. If your doctor or nurse puts you on a statin, stay on it. It can help prevent heart attacks, strokes, and death.
It’s possible to lower your cholesterol without medicines. Here are some steps you can take:
- Avoid red meat, butter, fried foods, cheese, and other foods that have a lot of saturated fat
- If you are overweight, take steps to bring your weight to keep it ideal for your height and weight (called BMI or Body Mass Index)
- In general, be more active
Even if these steps do little to change your cholesterol, they can improve your health in many ways.