Final answer:
A serum cholesterol level above 240 mg/dL puts a person at risk for CAD. Elevated LDL blood lipid profiles indicate an increased risk of heart attack, while elevated HDL blood lipid profiles indicate a reduced risk.
Step-by-step explanation:
The serum cholesterol level that puts a person at risk for coronary artery disease (CAD) is a total cholesterol level above 240 mg/dL. In particular, elevated LDL (low-density lipoprotein) blood lipid profiles indicate an increased risk of heart attack, while elevated HDL (high-density lipoprotein) blood lipid profiles indicate a reduced risk. According to research, the LDL:HDL ratio is a better predictor of heart disease risk than the overall level of serum cholesterol.