Cholesterol is a waxy, fat-like substance that is an essential structural component of all cell membranes and serves as the precursor for steroid hormones, vitamin D, and bile acids. Your liver produces all the cholesterol your body needs, though dietary sources (meat, eggs, dairy) also contribute to circulating levels.
Cholesterol has critical physiological functions. It regulates membrane fluidity and permeability, enables cell signaling through specialized membrane microdomains, and provides the molecular backbone for glucocorticoids, mineralocorticoids, sex hormones, and vitamin D—all essential for metabolic, reproductive, and bone health. Unlike other nutrients, humans cannot degrade cholesterol, so excess accumulates in the body unless converted to hormones or excreted via bile.
Types of Cholesterol
Because cholesterol is not water-soluble, it circulates in blood packaged within lipoproteins. The major types include:
- LDL cholesterol (“bad” cholesterol): Low-density lipoprotein carries 60-70% of plasma cholesterol and is the main contributor to arterial plaque formation. Levels <100 mg/dL are optimal, while ≥190 mg/dL is very high.
- HDL cholesterol (“good” cholesterol): High-density lipoprotein accounts for 20-30% of plasma cholesterol and removes excess cholesterol from tissues for liver excretion. Levels ≥60 mg/dL are protective against heart disease, while <40 mg/dL increases cardiovascular risk.
- VLDL and remnant cholesterol: Very low-density lipoproteins and their remnants carry triglycerides and contribute to atherosclerosis.
Normal Levels
For adults, desirable total cholesterol is <200 mg/dL, with 200-239 mg/dL considered borderline high and ≥240 mg/dL high. However, optimal cardiovascular health may require lower targets—evidence suggests LDL-C around 70 mg/dL may halt atherosclerotic plaque progression.
Cholesterol and lipid management remains the cornerstone of cardiovascular disease prevention and treatment. Low-density lipoprotein cholesterol (LDL-C) is the primary atherogenic lipoprotein, with extensive evidence demonstrating a causal relationship between elevated LDL-C and atherosclerotic cardiovascular disease (ASCVD). The fundamental principle guiding modern lipid management is that lower LDL-C levels achieved through evidence-based therapies translate to reduced cardiovascular risk across a continuum.
Dietary Patterns for LDL-C Reduction
The American College of Cardiology (ACC) and American Heart Association (AHA) recommend a diet emphasizing intake of fruits, vegetables, nuts, legumes, whole grains, and fiber, while replacing saturated and trans fats with dietary monounsaturated and polyunsaturated fats to decrease LDL-C levels and reduce ASCVD risk in adults and children with or without ASCVD.
The Portfolio diet, which combines nuts, soy protein, fiber, and plant sterol-enriched margarine, achieved the most substantial LDL-C reduction of 26 mg/dL.
Saturated Fat Replacement
An important component of controlling LDL-C through diet is avoiding saturated fat, which is typically found in red meat, butter, high-fat milk, coconut oil, and palm and palm kernel oil (tropical oils). There is a graded association between elevated LDL-C levels and intake of saturated fat. When saturated fats are replaced with unsaturated fats, there is a strong association with reduced LDL-C levels.
Sources of polyunsaturated fats include fish, nuts, flax and chia seeds, and oils (particularly corn, sunflower, and soybean oil). Sources of monounsaturated fats include olive oil, avocados, and nuts. Focusing on healthy eating patterns that limit saturated fat while increasing unsaturated fat produces more consistent LDL-C lowering than restricting dietary cholesterol.
Specific Food Components
Individual dietary components provide modest but meaningful LDL-C reductions:
- One serving of nuts per day: 4.8 mg/dL decrease in LDL-C
- Three daily servings of oatmeal (28 g each): 5 mg/dL decrease in LDL-C
- Plant-based protein sources compared to meat: 7.7 mg/dL LDL-C lowering
Integration with Overall Prevention
Health behavior counseling, particularly focused on diet, is essential for all individuals regardless of ASCVD risk level. The 2019 AHA/ACC Guideline on Primary Prevention recommends a diet emphasizing vegetables, fruits, legumes, nuts, whole grains, and fish to decrease ASCVD risk factors. Dietary patterns that are predominantly plant-based (Mediterranean, DASH, vegan/vegetarian) have the strongest evidence for both LDL-C reduction and improvement in cardiovascular outcomes.
The evidence supporting dietary modification for lipid management extends beyond LDL-C reduction to demonstrate cardiovascular outcomes benefits. A comprehensive diet that is low in saturated fats, low in refined carbohydrates, and relatively rich in unsaturated fats (particularly polyunsaturated fats) and protein (particularly plant-based protein), enriched with nuts, plant phytosterols, and high-fiber foods can potentially reduce plasma LDL levels by 30 to 40 mg/dL. [2-3]
Evidence-Based Dietary Patterns
The Mediterranean diet supplemented with extra virgin olive oil or nuts demonstrated reduced major adverse cardiovascular events in the PREDIMED trial among high-risk primary prevention individuals.
The DASH diet and Mediterranean-style eating patterns are consistently associated with improved cardiovascular outcomes in randomized controlled trials and observational studies.
Recent evidence from a 2025 European Society of Cardiology scientific statement confirms that plant-based dietary patterns rich in minimally processed foods, vegetables, and fruits reduce CVD risk, while patterns rich in ultra-processed foods, meat, salt, sugar, and saturated fat increase risk. The Mediterranean, DASH, and vegetarian diets all reduce CVD risk, though vegan diets offer no additional benefit over vegetarian approaches.
Practical Dietary Recommendations
Nutritional guidelines recommend diets rich in:
- Fruits and vegetables: ≥5 servings/day (≥1 serving/day of dark green or orange vegetables)
- Whole grains: primarily whole grain products
- Legumes, high-fiber cereals, nuts
- Low-fat dairy products, fish, lean meats, skinless poultry
- Unsaturated oils (olive, corn, sunflower, soybean)
Specific limits include:
- Saturated fat: <7% of total calories (some guidelines suggest 5-6%)
- Trans fats: <1% of total calories
- Dietary cholesterol: <200 mg/day
- Sodium: 2 g daily for those with hypertension
Supplemental Dietary Components
LDL-C lowering can be augmented by supplementing with:
- Plant stanol esters: ~2 g daily
- Soluble fiber: 10-25 g daily
Triglyceride Management
For hypertriglyceridemia, dietary strategies are critical and should focus on limiting simple carbohydrates (particularly processed carbohydrates and all added sugars), which results in substantial triglyceride lowering.
The 2026 ACC/AHA Dyslipidemia Guidelines: Key Updates
Risk Assessment and Treatment Thresholds
The guidelines now recommend using the PREVENT (Predicting Risk of cardiovascular disease EVENTs) equations instead of the older Pooled Cohort Equations for 10- and 30-year risk assessment in adults aged 30 to 79 years. The “CPR” model guides clinical decision-making: Calculate 10-year ASCVD risk, Personalize the risk estimate by considering factors not in the equations, and possibly Reclassify using coronary artery calcium (CAC) scoring.
Treatment thresholds have been refined. LDL-lowering therapy can be considered for borderline risk (3% to 5% 10-year risk) and should be considered for intermediate risk (5% to 10% 10-year risk) after clinician-patient discussion. For high-risk individuals (≥10% 10-year risk), high-intensity statin therapy is recommended.
Return of Treatment Goals
A major shift in the 2026 guidelines is the reintroduction of specific LDL-C and non-HDL-C treatment goals, moving beyond percentage reduction alone. For primary prevention at borderline or intermediate risk, the goal is LDL-C 100 mg/dL and non-HDL-C 130 mg/dL. For high-risk primary prevention, targets are LDL-C 70 mg/dL and non-HDL-C 100 mg/dL. In secondary prevention for very high-risk patients, the goal is LDL-C 55 mg/dL and non-HDL-C 85 mg/dL, with most patients with established ASCVD qualifying for these lower targets.
Emerging Risk Markers
The guidelines emphasize measuring lipoprotein(a) Lp(a) at least once in all adults. Lp(a) ≥125 nmol/L (50 mg/dL) is associated with approximately 40% increased ASCVD risk, while levels ≥250 nmol/L (100 mg/dL) confer at least 2-fold higher risk. Elevated Lp(a) should prompt more intensive LDL-C lowering.
Apolipoprotein B (ApoB) testing is useful for risk assessment and guiding therapy, particularly in patients with elevated triglycerides, diabetes, or low achieved LDL-C levels.
Statin Therapy: Foundation of Treatment
Statins remain the first-line therapy for both primary and secondary prevention. High-intensity statins (atorvastatin 40-80 mg or rosuvastatin 20-40 mg) typically reduce LDL-C by ≥50%, while moderate-intensity statins achieve 30-49% reduction. The cardiovascular benefit of statins is proportional to the absolute LDL-C reduction achieved.
For secondary prevention, high-intensity or maximally tolerated statin therapy is recommended for all patients with clinical ASCVD. In primary prevention, statin therapy is recommended regardless of LDL-C level for adults aged 40-75 years with diabetes, chronic kidney disease stage 3 or 4, or HIV infection.
Nonstatin Therapies: Expanding the Arsenal
Ezetimibe
Ezetimibe blocks intestinal cholesterol absorption and reduces LDL-C by approximately 18% as monotherapy or provides an additional 25% reduction when added to statin therapy. The IMPROVE-IT trial demonstrated that adding ezetimibe to statin therapy in post-acute coronary syndrome patients reduced cardiovascular events. Ezetimibe is well-tolerated with minimal side effects and is typically the first nonstatin agent added to statin therapy.
PCSK9 Inhibitors
Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors represent a major advance in lipid-lowering therapy. Two monoclonal antibodies are available:
- Alirocumab (Praluent): 75-150 mg subcutaneously every 2 weeks or 300 mg every 4 weeks
- Evolocumab (Repatha): 140 mg subcutaneously every 2 weeks or 420 mg monthly
PCSK9 monoclonal antibodies reduce LDL-C by 45-64% and have demonstrated cardiovascular event reduction in the FOURIER and ODYSSEY Outcomes trials. Extended safety data over 8 years show excellent tolerability with median achieved LDL-C levels of 30 mg/dL without safety concerns. The 2026 guidelines no longer require ezetimibe to be added before initiating a PCSK9 inhibitor, allowing flexibility based on the degree of LDL-C reduction needed and patient preference.
Inclisiran (Leqvio) is a small-interfering RNA-based PCSK9 inhibitor administered by healthcare professionals at initial dose, 3 months, then every 6 months. It reduces LDL-C by 48-52%. Inclisiran may be preferred for patients with poor adherence to self-injected therapies or those unable to self-inject.
Bempedoic Acid
Bempedoic acid (Nexletol) is an oral ATP citrate lyase inhibitor that reduces LDL-C by 21-24% as monotherapy in patients with statin-attributed side effects, or by an additional 17-18% when combined with statins. The CLEAR Outcomes trial demonstrated that bempedoic acid reduces cardiovascular events in patients unable to tolerate recommended statin therapy. It is a prodrug activated primarily in the liver, which may explain its better tolerability compared to statins. Caution is advised in patients with history of gout or tendon rupture.
Bile Acid Sequestrants
Cholestyramine and colesevelam bind bile acids in the gut, reducing LDL-C by 10-27%. While they have cardiovascular outcomes data from older trials, gastrointestinal side effects and drug-drug interactions limit their use. They are nonsystemic and may be useful in specific situations such as pregnancy or statin intolerance.
Special Populations requiring intensive treatment include:
- Familial Hypercholesterolemia
- Diabetes Mellitus
- Chronic Kidney Disease
Coronary Artery Calcium Scoring
CAC scoring in men ≥40 years and women ≥45 years can improve risk assessment and guide treatment decisions. A CAC score of zero may allow deferral of statin therapy (except in smokers, diabetics, or those with strong family history of premature ASCVD). CAC ≥100 Agatston units or ≥75th percentile strongly favors statin therapy. Both absolute CAC and age-sex-race percentile provide prognostic information.
Practical Implementation
The 2026 guidelines emphasize early treatment to reduce lifelong exposure to atherogenic lipoproteins. Health behavior, including dietary counseling should start in youth, with pharmacotherapy considered early in familial hypercholesterolemia and young adults with LDL-C ≥160 mg/dL or strong family history of premature ASCVD.
Monitoring should occur 4-12 weeks after statin initiation or dose adjustment, then every 3-12 months as needed. Both percentage LDL-C reduction and absolute LDL-C goals should guide therapy intensification.
The sequential approach to nonstatin therapy typically follows: statin optimization → ezetimibe → PCSK9 inhibitor or bempedoic acid, with choices based on degree of LDL-C reduction needed, patient preferences, cost considerations, and tolerability.
