You know many important numbers, such as your age, your birth date, and your phone number. But do you know your blood pressure, low-density lipoprotein (LDL) cholesterol level, or body-mass index (BMI)? How about your waist circumference, blood glucose level, or triglyceride level? More importantly, do you know what these numbers should be? The information could very well save your life.

Blood pressure, LDL cholesterol, triglycerides, BMI, waist circumference, and blood glucose are modifiable risk factors for coronary artery disease (CAD). This common disease leads to more than 735,000 heart attacks and 370,000 deaths every year. Most heart attacks can be prevented if people know their risk factors and take control of them.

The numbers discussed below are based on the interpretation of the best scientific evidence today. Your doctor’s opinion may differ somewhat—and that’s okay. There are guidelines for treating these risk factors and that simply means the recommendations should be used to inform judgment. What might be best for one person might not be optimal for another.

You are in control of your heart health. If you strive to attain recommended levels of these risk factors, you will lower your risk of developing CAD and having a heart attack. That’s why these numbers—and your own numbers—are very important to know. Here are the six numbers you need to know by heart:

Blood Pressure: 120/80

Man having blood pressure taken — SolStock/iStock

Your blood pressure should be no higher than 120/80 mmHg (millimeters of mercury). The top number represents the pressure when your heart is contracting to push blood into your lungs and body. The bottom number is the pressure when your heart is relaxing and refilling with blood.

When blood pressure rises above 120/80 mmHg, the heart muscle has to pump harder to do its job. The harder it pumps, the thicker it becomes. A thick heart muscle cannot pump efficiently. There is also evidence that high blood pressure rushing through the arteries damages the artery walls and accelerates the development of CAD.

The higher the blood pressure becomes, the more dangerous it is. You may be unaware this is happening—rising blood pressure produces no symptoms. (That’s why your doctor takes your blood pressure reading at every visit.)

If your blood pressure is higher than 120/80 mmHg, your doctor may recommend lifestyle interventions, such as exercise, to help bring it down. When blood pressure is higher than 140/90, many people require one or more anti-hypertension medications to lower it.

LDL Cholesterol: 100

Low-density lipoprotein (LDL) cholesterol is the primary form of fat circulating in the bloodstream that can end up deposited in artery walls. Ideally, your LDL level should be no higher than 100 mg/dL (milligrams per deciliter) and certainly less than 130 mg/dL. Like blood pressure, the higher it goes, the greater the risk of heart attack.

The amount of LDL and other fats in your blood can be measured with a basic blood test. You should have this test every five years starting at age 20—more often if your doctor recommends it.

If your LDL is higher than it should be, you can make changes in your life to lower it. Some people also need cholesterol-lowering medication to bring the number down.

Triglycerides: 150

Triglycerides are another form of fat that circulates in the bloodstream and appear to play a role in heart disease. Just how they affect the heart is not fully understood, however.

Triglycerides are increased when you consume simple carbohydrates, such as sugars, breads, baked goods, and alcohol. Most people find that reducing these carbohydrates in their diet can lower triglyceride levels.

BMI: 18.5-24.9

Body mass index is a measure of your weight when adjusted for your height. Excess fat causes the heart to work harder and raises blood pressure. Being overweight lowers levels of “good” HDL (high-density lipoprotein) cholesterol that helps to clean cholesterol from the arteries.

Ultimately, too much extra fat can cause metabolic syndrome—a constellation of risk factors—and lead to diabetes, a major driver of heart disease.

Waist Circumference: 32 or 37

Being overweight is dangerous. But being apple-shaped is more dangerous than carrying your extra pounds in your hips. A larger waist is associated with a higher level of inflammation in the body. And inflammation can trigger heart disease.

After age 35, women should strive for a waist circumference of 32 inches or less. For men, it’s important to have a waistline of 37 inches or less after age 40.

Fasting Glucose: 100

The amount of sugar in your blood after fasting for eight hours can determine the likelihood that you will develop diabetes. The association between diabetes and CAD is so strong that, if you have diabetes, there is a good chance you will develop heart disease too, even if you have no other risk factors.

Blood glucose levels are taken with a quick blood test and should be less than 100 mg/dL. If your level is higher, losing weight will often bring it down.

Dr. Nissen is a cardiologist and chairman of the department of cardiovascular medicine at Cleveland Clinic's Heart and Vascular Institute, the nation's No. 1 cardiology and heart surgery program as ranked by U.S. News & World Report.