What High LDL Cholesterol Means for Your Health: Causes, Tests, and Dietary Factors

Managing cholesterol levels is essential for safeguarding against heart disease and promoting longevity. According to a study published in JAMA Cardiology, approximately 1 in 17 American adults have high LDL cholesterol levels ranging from 160 to 189 mg/dL, while 1 in 48 have levels of 190 mg/dL or higher.

Alarmingly, many individuals in these groups are either unaware of their condition or are not receiving appropriate treatment. Given that elevated cholesterol is a significant risk factor for cardiovascular disease and mortality, targeted interventions to lower cholesterol pave the way for a longer, healthier life.

[signup]

What Is LDL Cholesterol?

Low-density lipoprotein (LDL) is one of the five major groups of lipoproteins, which are complexes made of lipids and proteins. These particles transport fats in the bloodstream and deliver them to cells throughout the body.

Each LDL particle consists of a core of cholesterol and triglycerides surrounded by a shell of phospholipids with a single protein component called apolipoprotein B-100 (ApoB-100).

‍Cholesterol is a waxy, fat-like substance, or lipid, that comes from two primary sources: endogenous production and dietary intake. The liver is the main site of endogenous cholesterol synthesis, producing about 80% of the body's total cholesterol. The remaining 20% comes from dietary sources, particularly animal products.

Cholesterol is found in all cell membranes, where it contributes to membrane fluidity and stability. It is also a precursor for the synthesis of steroid hormones, bile acids, and vitamin D. (40)

LDL cholesterol (LDL-C) specifically refers to the cholesterol contained within LDL particles.

LDL-C is often compared to high-density lipoprotein cholesterol (HDL-C), which is the cholesterol carried by high-density lipoproteins (HDL). HDL picks up and shuttles excess cholesterol away from the arteries to the liver for elimination, reducing the risk of atherosclerosis and conferring protective effects on the cardiovascular system.

What Does High LDL Cholesterol Mean?

LDL-C is often labeled as "bad cholesterol" due to its propensity to deposit cholesterol in the arterial walls, forming plaques. Over time, these plaques can thicken and harden, causing the arteries to narrow, which restricts blood flow. This process, known as atherosclerosis, can lead to coronary artery disease (CAD), peripheral artery disease (PAD), and serious cardiovascular events, such as heart attacks and strokes. Therefore, lowering LDL-C is a primary goal for reducing cardiovascular risk.

What Causes High LDL Cholesterol?

A combination of modifiable and non-modifiable factors can raise LDL-C levels:

Genetics: If your family members have high cholesterol, you might have a higher risk, too.
Age: High cholesterol is more common in people over 40 because the liver becomes less effective at removing LDL-C with age.
Underlying Medical Conditions: You can have higher LDL-C levels if you have diabetes, chronic kidney disease (CKD), hypothyroidism, liver disease, HIV/AIDS, or obesity.
Diet: Eating an unhealthy diet that has too many saturated and trans fats will raise LDL-C
Sedentary Lifestyle: A lack of physical activity is a risk factor for high cholesterol.
Alcohol: Heavy drinking (15 or more drinks per week for men or eight or more drinks per week for women) is linked to high LDL-C levels.
Smoking: Tobacco increases the number of LDL particles and reduces the amount of HDL particles in the bloodstream, both of which can lead to elevated cholesterol levels.
Medications: Some medications can cause LDL-C levels to increase. These include birth control pills, corticosteroids, antivirals, diuretics, and immunosuppressants.

Lab Tests for LDL Cholesterol

Diagnosing high LDL-C requires a lipid panel, which measures various lipids in the blood, including:

Total cholesterol (TC)
LDL-C
Very low-density lipoprotein (VLDL) cholesterol
HDL-C
Triglycerides (TG)

Traditionally, fasting 10-12 hours before a lipid panel was standard practice. Fasting ensures that recent food intake does not affect triglyceride levels, which can subsequently influence LDL-C calculations.

However, recent guidelines suggest that non-fasting lipid panels can be just as effective for most routine assessments. Your healthcare provider may recommend fasting if there is a specific concern about triglyceride levels or if previous tests showed borderline or high levels. (27)

A normal LDL-C level is less than 100 mg/dL. If you have high LDL-C, risk stratification can help determine the likelihood of developing cardiovascular disease (CVD). (42)

Near Optimal: 100-129 mg/dL
Borderline High: 130-159 mg/dL
High: 160-189 mg/dL
Very High: 190 mg/dL and higher

Order a lipid panel through Rupa Health with one of the following tests:

Lipid Panel Basic by Boston Heart Diagnostics
Lipid Panel by Access Med Labs
Lipid Panel by Access Labcorp Draw
Cholesterol and Lipids Panel by Ayumetrix

Additional Testing for High LDL Cholesterol

Advanced lipid testing offers a more comprehensive and nuanced assessment of CVD risk because it utilizes biomarkers that delve deeper into the characteristics and behaviors of lipid articles in the bloodstream.

LDL Particle Number and Size

Not all LDL particles are created equal. Small, dense LDL particles are more atherogenic (more likely to promote the formation of plaques in the arteries) than larger, buoyant LDL particles. This is because small, dense LDL particles can more easily penetrate the endothelial lining of arteries and are more prone to oxidation, which is a critical step in the development of atherosclerosis.

By qualifying the number and size of LDL particles in circulation, advanced lipid testing can identify patients who may be at higher risk for CVD despite having levels of LDL-C similar to those of others with lower risk.

Measure LDL particle number and size with the NMR LipoProfile by Access Med Labs.

Oxidized LDL (OxLDL)

OxLDL is a form of LDL that has undergone oxidative modification when LDL particles react with free radicals. Elevated levels of OxLDL are strongly associated with accelerated formation of atherosclerotic plaques in the arterial walls. (50)

Measure OxLDL with one of the following tests:

Oxidized LDL by Access Med Labs
OxLDL by Boston Heart Diagnostics

Apolipoprotein B (ApoB)

ApoB correlates to the number of atherogenic lipid particles in circulation and is a more accurate predictor of CVD risk than TC or LDL-C (48). High levels of ApoB confer a higher risk of developing CVD, even when LDL-C levels are low (68).

Measure ApoB with one of the following tests:

Apolipoprotein B (Apo-B) by Access Med Labs
Apolipoprotein B by Access Labcorp Draw
Apolipoprotein B (ApoB) by Boston Heart Diagnostics

Lipoprotein(a) (Lp(a))

Lp(a) (pronounced "lipoprotein little a") is a type of LDL that has an extra protein on its surface called apolipoprotein(a), increasing its ability to promote the formation of fatty deposits in the arteries. Lp(a) levels are predominantly genetically determined. High levels (greater than or equal to 50 mg/dL) increase the risk of CVD. (45)

Measure Lp(a) with one of the following tests:

Lipoprotein(a) by Access Med Labs
Lipoprotein(a) by Access Labcorp Draw
Lipoprotein(a) (Lp(a)) by Boston Heart Diagnostics

High-Sensitivity C-Reactive Protein (hs-CRP)

Oxidation of LDL particles triggers an inflammatory response. Hs-CRP is an inflammatory marker that can detect low levels of inflammation. Elevated hs-CRP (greater than 1 mg/dL) is linked to an increased risk of heart attacks and strokes.

Measure hs-CRP with one of the following tests:

C-Reactive Protein, High Sensitivity (CRP, HS) by Access Med Labs
High Sensitivity C-Reactive Protein (hs-CRP) by Boston Heart Diagnostics

What Foods Cause High LDL Cholesterol?

While it used to be believed that dietary cholesterol, such as that found in eggs, significantly impacts LDL-C levels, recent research suggests that this is not the case for most people. Instead, saturated and trans fats have a more substantial effect on raising LDL-C levels.

‍Saturated fats are primarily found in animal products and some plant oils. Common sources include:

Red meat
Full-fat dairy products
Lard
Tallow
Coconut

Trans fats are artificially created through hydrogenation, which solidifies liquid oils. They are found in:

Fried foods
Commercial baked goods
Snack foods
Margarine
Shortening

Managing High LDL Cholesterol

Managing high LDL-C involves lifestyle changes, medications, and natural supplements.

Regular monitoring of LDL-C ensures that interventions are effective and guides treatment modifications. General recommendations for lipid retesting include:

Retest LDL-C levels after 4-12 weeks to assess the initial response after starting a new medication or marking significant lifestyle changes.
Once LDL-C levels are stable, restest lipids every 3-12 months for ongoing monitoring. More frequent monitoring may be necessary for individuals with high cardiovascular risk or those undergoing significant treatment changes.

Lifestyle Changes

Adopt a heart-healthy diet to lower systemic inflammation and reduce LDL-C. Specifically:

Reduce saturated fat intake to less than 6% of total daily calories.
Replace saturated fats with unsaturated fats in olive oil, avocados, nuts, seeds, and fatty fish.
Eliminate trans fats.
Increase soluble fiber intake by eating whole grains, legumes, fruits, and vegetables. Fiber binds cholesterol in the digestive tract and inhibits its reabsorption into circulation.

Regular physical activity lowers LDL-C and raises HDL-C. Aim for at least 150 minutes of moderate-intensity aerobic exercise or 75 minutes of vigorous-intensity exercise per week. Examples of aerobic exercise include walking, jogging, cycling, and swimming.

Quitting smoking reduces the progression of atherosclerosis and improves HDL-C and HDL particle number (28, 57). This risk of heart attack significantly reduces within just 12 to 24 hours of quitting smoking.

Medications

Statins are the most commonly prescribed medications for lowering LDL-C. They inhibit HMG-CoA reductase, an enzyme involved in cholesterol synthesis in the liver. Statins are recommended as first-line treatment for the following groups:

Adults with clinical atherosclerotic CVD (ASCVD)
Adults with LDL-C 190 mg/dL or higher
Adults ages 40-75 with diabetes mellitus and LDL-C 70 mg/dL or higher
Adults ages 40-75 without diabetes mellitus with LDL-C levels of at least 70 mg/dL and a 10-year ASCVD risk of 7.5% or higher

‍Ezetimibe is the most commonly used non-statin medication and lowers cholesterol by inhibiting intestinal cholesterol absorption.

Bile acid sequestrants, such as cholestyramine, lower cholesterol by binding to bile acids in the intestines. This prevents cholesterol reabsorption and leads to increased liver conversion of cholesterol into bile acids.

PCSK9 inhibitors, including evolocumab and alirocumab, are injectable medications that lower LDL-C by enhancing the liver's ability to remove LDL particles from the blood. They are typically prescribed to individuals who cannot achieve target LDL-C levels with statins alone or who are statin-intolerant.

Natural Supplements

Certain natural supplements can effectively reduce LDL-C levels and are typically associated with fewer side effects than their pharmaceutical counterparts. Examples include:

Plant sterols: 2 grams daily
Red Yeast Rice: 1,200-4,800 mg per day in divided doses
Psyllium Husk: 10 grams daily
Niacin: 250-3,000 mg daily in divided doses
Berberine: 500 mg twice daily