Healthy number: Total cholesterol under 200 mg/dL; LDL cholesterol under 100 mg/dL.
“The higher your cholesterol levels, the greater your risk of heart disease,” says Nieca Goldberg, M.D., director of the Langone Women’s Heart Center at New York University, in New York City. To minimize health risks, your total cholesterol should stay under 200 mg/dL (cholesterol is measured by milligrams of cholesterol per deciliter of blood). But it’s actually low-density lipoprotein (LDL) cholesterol—the “bad,” artery-clogging kind—that causes the damage. “Elevated LDL levels cause the formation of plaque in the artery walls,” explains Goldberg, which leads to atherosclerosis and an increased risk of heart attack and stroke. For most people, the optimal level of LDL is under 100 mg/dL (and under 70 mg/dL if you have diabetes or heart disease).
Have yours checked: Starting at age 20 and older. “You should have a fasting blood test to measure total cholesterol and LDL, plus the other lipids, triglycerides, and HDL [high-density lipoprotein],” says Goldberg. “If the numbers are normal, you don’t have to recheck them for five years.” If the numbers are not where they should be, the best way to improve your cholesterol levels is to lose excess weight; exercise more often; stick with a diet that is low in cholesterol, saturated fat, and trans fats; and get your levels rechecked yearly. Even if you do all this, you may still need to take a cholesterol-lowering medication.