What Makes LDL Cholesterol High?

When your low-density lipoprotein (LDL) cholesterol is high, it means you have too much of the "bad" type of this fat-like substance in your blood. LDL cholesterol can build up and clog arteries, which can lead to health problems such as coronary artery disease (CAD), heart attack, and stroke.

A lot of factors can cause your LDL cholesterol to be high, including genetics, being overweight, diet, and more.

In this article, you'll learn what cholesterol levels are considered healthy versus high, how they're measured, and how various contributing factors increase your levels.

LDL Cholesterol: High Levels and Healthy Levels

Cholesterol is necessary for your body. Everyone has—and needs—some. It’s made in your liver and comes from certain foods, especially:

• Meats
• Eggs
• Dairy

LDL is a lipoprotein—a substance that carries cholesterol to cells. There, it helps maintain cell structure and provides ingredients for substances vital to your health and survival.

When you have too much LDL, though, it starts depositing cholesterol in your arteries. It forms a build-up called plaque (atherosclerosis), which impairs blood flow. This can lead to conditions such as a heart attack, stroke, or peripheral artery disease.

Measuring LDL

When your blood tests go to the lab, they're analyzed for their lipid profile (what lipids the blood contains and how much.) A lipid profile measures:

• LDL
• HDL
• A fatty lipid called triglycerides

It also gives you a total cholesterol score.

Healthy LDL

A healthy LDL level is measured in terms of milligrams (mg) per deciliter (dL) of blood, abbreviated as mg/dL). Your results can be in one of four categories, with ranges that vary with age.

If you have cardiovascular disease, your optimal LDL level is lower than 70 mg/dL.

The higher your LDL level, the more important it is to take steps to lower it.

How Lifestyle Makes LDL Cholesterol High

If your LDL levels are borderline or higher, you should work with your healthcare to lower your cholesterol numbers. One of the most important things you can do is make meaningful lifestyle changes.

Diet

What you eat can have a big impact on your LDL levels. Saturated fat, which, according to the American Heart Association, should make up only about 5% of your daily calories, can cause your LDL to be high.

Foods high in this fat include:

• Lard and cream
• Beef and beef fat
• Lamb and pork
• Skin-on chicken
• Butter and full-fat dairy, including full-fat cheese
• Palm oils

Other foods can help you manage LDL levels. Some good choices are:

• Lean proteins: Fish, skinless chicken, nuts, beans, fat-free or low-fat milk
• Low-fat foods: Fresh vegetables and fruits, whole grain bread, fat-free or low-fat yogurts and cheeses
  
• High-fiber foods: Leafy vegetables, oatmeal, beans, and apples
• Unsaturated fats: Avocados, nuts, and olive oil

Added sugar or corn syrup can also raise LDL, so avoid them. Read labels, as these can be in surprising places.

Unsaturated fats can help reduce LDL cholesterol levels while raising HDL.

How Your Weight Makes LDL Cholesterol High

Another major risk factor for high LDL is having excessive weight. It limits your body’s ability to remove this type of cholesterol from the bloodstream and is directly related to higher levels.

The most commonly used measure to evaluate weight is the body mass index (BMI). It uses weight and height to estimate body fat. The resulting number is then used to categorize people as:

• Underweight
• Normal weight
• Overweight
• Obese
• Morbidly obese

But BMI is not perfect. It doesn't account for other factors that determine body composition, like age, muscle mass, or sex. BMI calculations may, for example, overestimate body fat in athletes or in older people.

Even so, higher BMI scores should be addressed. Research has shown that even a modest reduction in weight—say, 5% to 10% of the starting figure—lowers LDL and reduces other cardiovascular risk factors.

Lack of Physical Activity

Low physical activity can also drive LDL higher. Even modest increases in exercise can help a great deal.

Your healthcare provider may suggest up to 90 minutes of physical activity a day, but even 30 to 45 minutes on a regular basis can be helpful.

At a bare minimum, most guidelines recommend that adults get 2.5 hours of moderate exercise every week. This can include:

• Biking
• Brisk walking
• Jogging
• Swimming

Tobacco and Alcohol

Among the many negative health effects of smoking/using tobacco are:

• Atherosclerosis
• Elevated LDL
• Lower HDL levels

Quitting this habit, or not starting, goes a long way in managing cholesterol and reducing your risk of heart disease and cancers.

Second-hand smoke—inhaling someone else's tobacco smoke—is linked with many of the same health problems. If you’re a smoker, smoke outside and away from nonsmokers. If you’re not a smoker, try to avoid second-hand smoke.  

Also, because of its many effects on the body, excessive alcohol consumption and alcoholism are linked with higher cholesterol levels. Limiting your drinking or stopping altogether can help you manage your levels.

How Age and Sex Make LDL Cholesterol High

Your age and sex can also have a significant influence on LDL levels. As people age, they usually rise.

Between the ages of 20 and 59, people assigned male at birth (AMAB) tend to have higher LDL levels than people assigned female at birth (AFAB). In contrast, people who were AFAB and over 60 typically have higher LDL values than those who were AMAB.

Menopause can also raise your risk of high LDL cholesterol. More frequent LDL monitoring is recommended when you're post-menopausal.

How Genetics Makes LDL Cholesterol High

As with many health conditions, a family history of high cholesterol increases the risk of your developing it.

One in every 500 people has a genetic condition called familial hypercholesterolemia (FH) that leads to high LDL levels. This condition is especially concerning because it‘s often undetected and is tied to early heart attacks, strokes, and deaths.

In FH, a gene that's essential for clearing LDL cholesterol from the bloodstream malfunctions. That's due to faulty receptor proteins.

If you only get this gene from one parent (heterogenous FH) about half of these proteins don't work. If you get one from each parent, it's called homogenous and the disease is more severe, as none of the proteins work.

If any of your family members have tough-to-treat high cholesterol, or you have a family history of heart disease, you may want to get genetic screening for FH.

How Ethnicity Makes LDL Cholesterol High

According to a growing body of research, ethnicity is a factor in high cholesterol levels. While people of any ethnicity can develop high LDL, the risk varies by ancestry and sex:

Medications That Make LDL Cholesterol High

Some prescription medications can also cause an elevated LDL level. You and your healthcare provider should weigh the risks and benefits of these drugs while considering your personal and family medical history.

Some drugs in the following classes can raise LDL levels.

Heart Disease and Blood Pressure Drugs

Drugs for heart conditions and high blood pressure can increase LDL levels. That makes managing your cholesterol levels both harder and more important. Classes of drugs that do this include:

• Loop diuretics: Bumex (bumetanide), Edecrin (ethacrynic acid)
• Thiazide diuretics: Zaroxolyn (metalozone), Lozol (indapamide)
• Sodium-glucose cotransporter 2 (SGLT2) inhibitors: Invokana (canagliflozin), Farxiga (dapagliflozin)

Steroids

These powerful anti-inflammatory medications can boost your cholesterol. Drugs in this category include:

• Danocrine (danazol)
• Anabolic steroids (synthesized testosterone)
• Some corticosteroids like Prednisone Intensol (prednisone) and Orapred (prednisolone)

Antiviral Drugs

Antiviral medications for HIV/AIDS and hepatitis C can be a problem as well. These include protease inhibitors such as:

• Viracept (nelfinavir)
• Incivek (telaprevir)
• Harvoni (ledipasvir)
• Fuzeon (enfuvirtide)

Immunosuppressants

Some immunosuppressant drugs, which are used to prevent rejection after organ transplants, may be a problem when it comes to LDL levels. That's especially true of:

• Cyclosporine
• Tacrolimus

Nervous System Drugs

Some drugs that act on the brain and central nervous system (CNS) may directly affect LDL. These include anticonvulsant drugs for epilepsy and other conditions, including:

• Depakote (valproic acid)
• Topamax (topiramate)

Other Health Conditions That Make LDL Cholesterol High

High cholesterol can also be caused by a range of other health conditions you may have. These include:

• Type 2 diabetes: Insufficient insulin production limits your body’s ability to process LDL.
• Liver disease: The liver helps clear cholesterol, so when it's impaired, levels may rise.
• Kidney diseases: The kidneys also play a central role in cleaning out your bloodstream, so problems such as chronic kidney disease can increase cholesterol levels.
• Pregnancy: Changes in the body during pregnancy often make cholesterol levels rise, which increases the risk of preeclampsia and eclampsia, two dangerous complications.
• Hypothyroidism: Low thyroid activity also interferes with LDL levels, enough so that high LDL often leads to thyroid testing.
  

Summary

LDL is considered "bad" cholesterol because too-high levels can lead to atherosclerosis in the arteries and contribute to problems like heart attack and stroke. Some factors that raise LDL levels cannot be changed, such as age, ethnicity, and genetics.

However, other factors are modifiable, and can help you treat high LDL. These include lifestyle habits like diet, exercise, and smoking. Changing these factors is usually the first step towards lowering LDL.

A Word From Verywell

Given how fundamental cholesterol is to the processes of the body and the function of the circulatory system, it’s little wonder that many factors can cause high LDL. Because there are so many dangers associated with it, high LDL may be something to worry about. However, figuring out what specific behaviors, medications, or other issues are causing the problem can be key in solving it.

Ultimately, there is no singular method for treating high LDL; what works for some, doesn’t work as well for others. Getting this to a healthy level is a journey, rather than an event. That said, with the support of loved ones and the guidance of health professionals, your cholesterol can be effectively managed. The benefits of that work, of course, are boundless.