Atherosclerotic cardiovascular disease (ASCVD) remains the leading cause of death in the United States. Most individuals who develop ASCVD have at least 1 antecedent major risk factor, and very few have optimal levels of all risk factors and behavioral factors. Lifestyle and behavioral factors are the foundation of ASCVD prevention, and maintaining healthy habits can help preserve good cardiovascular health over the life course. The key to effective prevention is a comprehensive approach, emphasizing a healthy lifestyle and addressing all major risk factors. The 2019 American College of Cardiology (ACC)/American Heart Association (AHA) Guideline on the Primary Prevention of Cardiovascular Disease incorporates existing guidelines, statements, and consensus documents into a single comprehensive resource for patients, health care professionals, and public health officials.1 Recommendations to prevent ASCVD (coronary heart disease, stroke, and peripheral artery disease), atrial fibrillation, and heart failure in adults include lifestyle factors (eg, nutrition, exercise or physical activity, overweight and obesity, and tobacco use) and treatment-associated factors (eg, risk assessment, blood pressure level, blood cholesterol level, diabetes, and aspirin use). This article focuses on lifestyle factors.