Cholesterol is a waxy substance found in your blood that your body needs to build healthy cells, but high levels can increase your risk of heart disease. There are two main types of cholesterol: 1. LDL (Low-Density Lipoprotein) - "Bad" cholesterol: - Builds up in artery walls - Forms plaques that can block blood flow - Ideal level is below 100 mg/dL 2. HDL (High-Density Lipoprotein) - "Good" cholesterol: - Carries LDL away from arteries - Returns it to liver for processing - Ideal level is 60 mg/dL or higher Factors affecting cholesterol levels: - Diet (saturated and trans fats raise LDL) - Weight (being overweight increases LDL) - Physical activity (exercise boosts HDL) - Age and gender (levels tend to rise with age) - Genetics (family history plays a role) Dietary changes to improve cholesterol: - Reduce saturated fats (found in red meat, full-fat dairy) - Eliminate trans fats (found in fried foods, baked goods) - Eat omega-3 rich foods (salmon, walnuts, flaxseeds) - Increase soluble fiber (oats, beans, lentils, fruits) - Add whey protein (found in dairy products) When lifestyle changes aren't enough, medications like statins may be prescribed. Newer options include PCSK9 inhibitors for difficult-to-control cases. Regular cholesterol screening is recommended starting at age 20, or earlier if you have risk factors.