High cholesterol, specifically high LDL (“bad”) cholesterol, is a major risk factor for cardiovascular disease. As a result, high cholesterol can play a key role in life threatening conditions like heart attack and stroke.

Cholesterol levels, however, can often be lowered through a combination of diet, exercise, and, if necessary, medications. The key is to work with your doctor to address your cholesterol levels as well as other risk factors for cardiovascular complications.

This article will take a closer look at why high cholesterol can be dangerous to your health and what you can do to reduce the risk of complications.

At the right levels, cholesterol is actually an essential substance in your body. It plays an important role in building cells, producing hormones, and aiding digestion.

But cholesterol can also be harmful if there’s too much of it circulating in your bloodstream.

The main health risk associated with high cholesterol is the formation of fatty deposits, known as plaque. This plaque can build up along the inner walls of your arteries — the blood vessels that carry blood from your heart to the rest of your body.

When plaque builds up, it can cause your arteries to become narrow and less flexible. This is called atherosclerosis, and it can raise your risk of a heart attack and stroke as well as other serious complications.

So, how do you know whether your cholesterol is at the right level? The only way to know for sure is to get your blood tested.

This blood test is known as a lipid panel or lipid profile. It measures the levels of lipids (fats) in your blood that affect your cholesterol level. This includes:

  • Low-density lipoprotein (LDL) cholesterol: LDL cholesterol is considered the “bad” type of cholesterol. That’s because having too much of it in your bloodstream can cause fatty deposits (plaque) to accumulate on the walls of your arteries.
  • High-density lipoprotein (HDL) cholesterol: HDL cholesterol is considered the “good cholesterol” because it helps move LDL cholesterol out of your bloodstream and back to the liver, where it can be flushed out of your body. Ideally, HDL cholesterol levels should be 40 mg/dL or higher.
  • Triglycerides: Triglycerides are blood fats that are similar to cholesterol, but they don’t help support cells or hormone production. Triglycerides carry unused calories from the food you eat.
  • Total cholesterol: Total cholesterol is the sum of your LDL and HDL levels and 20% of your triglycerides. The Centers for Disease Control and Prevention (CDC) reports that more than one-third of adults in the United States have high total cholesterol.
What’s considered high cholesterol?

According to the National Library of Medicine, your cholesterol level may be considered high or borderline high if your:

  • total cholesterol is above 200 mg/dL
  • LDL cholesterol level is above 130 mg/dL
  • triglyceride level is above 150 mg/dL

The following life threatening complications can be caused by high cholesterol levels.

High blood pressure (hypertension) means the force of blood against the walls of the arteries is higher than it should be. Narrowed, stiffer arteries caused by high cholesterol and plaque buildup are major causes of high blood pressure.

High blood pressure can lead to a stroke or heart attack. Both of those events can be fatal if they’re severe enough or if you don’t get proper treatment in time. According to the American Heart Association, hypertension is also a risk factor for:

  • eye damage that can lead to vision loss
  • heart failure, which is a major weakening of the heart muscle
  • sexual dysfunction

When one or more of the coronary arteries — the arteries that supply blood to the heart muscle — narrow due to atherosclerosis, the risk of a heart attack increases substantially.

One of the major risks is that plaque that’s built up on an artery wall will rupture. This can trigger the release of certain blood cells and proteins that rush to the site of the rupture and form a blood clot. When this happens, the clot can block the normal flow of blood to the heart.

While many people are able to survive a heart attack, in some cases, the heart becomes so starved for oxygen-rich blood that it leads to severe complications or death.

According to research, about 12% of people in the United States who have a heart attack die from the event.

There are two main types of stroke, both of which can be fatal:

  • Hemorrhagic stroke: This stroke occurs when a blood vessel in the brain ruptures, leaking blood into nearby brain tissue.
  • Ischemic stroke: This stroke occurs when an artery supplying blood to the brain becomes blocked.

In both types of stroke, high cholesterol can be a contributor.

Atherosclerosis can weaken blood vessels, making them more likely to rupture. In addition, plaque rupture and the subsequent formation of a blood clot can occur in an artery in the brain or in the carotid arteries, which carry blood up to the brain along either side of the neck.

The CDC reports that about 1 in 6 deaths among people with cardiovascular disease is due to a stroke.

Plaque buildup from arteriosclerosis can also cause the blood vessels in your limbs to narrow. This is known as peripheral vascular disease (PVD).

This condition can be painful, as the muscles get less blood flow than usual. Reduced blood flow can cause tissue damage and even tissue death, which may lead to limb amputation.

PVD may also increase the risk of blood clot formation, which could ultimately prove fatal if the clot travels from the leg to the lungs, for example, resulting in a pulmonary embolism.

According to a 2018 study, pulmonary embolisms cause about 100,000 deaths in the United States each year.

One of the main functions of the kidneys is to filter waste matter and toxins out of the blood and eventually out of the body. High cholesterol levels are associated with poor filtration and a higher risk of kidney disease.

Kidney disease is a major risk factor for cardiovascular disease and heart attack.

If not treated effectively at the outset, kidney problems can lead to chronic kidney disease (CKD).

A 2019 study suggests that the mortality rate for individuals with CKD is significantly higher than it is for similar individuals with diabetes or hypertension and no CKD.

Despite being a risk factor for many serious health problems, high cholesterol is a manageable condition for most people.

You may be able to prevent cholesterol from causing serious health issues by taking the following steps:

  • Get your cholesterol checked: Be sure to get your LDL, HDL, triglycerides, and total cholesterol checked as part of your annual physical examination. If you’re actively working to get your cholesterol under control, your doctor may advise you to have your cholesterol checked more frequently.
  • Eat a heart-healthy diet: To protect your heart health and reduce the risk of high cholesterol, consider following an eating plan such as the Mediterranean diet or the Dietary Approaches to Stop Hypertension (DASH) diet. Both of those eating plans focus on meals rich in vegetables, fruits, lean proteins, whole grains, and low fat dairy products.
  • Get regular exercise: Regular exercise can also help increase your HDL cholesterol levels. This, in turn, may help lower your LDL cholesterol. To get the most rewards from exercise, try to be physically active for at least 30 minutes a day, most days of the week. You can break this down into 15-minute exercise routines twice a day if it’s hard for you to fit a 30-minute workout into your schedule.
  • Quit smoking: Smoking can negatively affect your health in many ways. Not only can it raise your risk of cancer and lung disease, but it can also stiffen your blood vessels, making it easier for cholesterol plaques to build up on your artery walls.
  • Take your cholesterol medication: If you’ve been diagnosed with high cholesterol, your doctor may have prescribed LDL-lowering medications. Statins are the most widely used of these medications. Numerous studies, including a 2021 study of people over the age of 60, suggest that statin use is associated with significantly lower mortality risks. If statins cause side effects, there are other medication options.

High cholesterol is a condition that has no symptoms, but it can be easily diagnosed with a blood test.

But even without noticeable symptoms, high cholesterol can significantly increase the risk of cardiovascular disease and other life threatening health problems.

By making lifestyle changes, taking cholesterol-lowering medication, and following your doctor’s advice, you can lower your cholesterol and reduce the risk of potentially fatal events, such as a heart attack or stroke.