Getting your blood pressure checked is one of the first things that happens when you see your doctor. It’s a basic indicator of health.

High blood pressure, or hypertension, is dangerous because it makes your heart work harder than it should to pump blood. High blood pressure can trigger many conditions that cause serious health problems.

More than 74 million U.S. adults have been diagnosed with high blood pressure, according to the American Heart Association.

When your health care provider measures your blood pressure, he or she collects two numbers. The first number, called the systolic pressure, is the pressure of your blood being pushed through your circulatory system. The second number, called the diastolic, is your heart at rest.

Here’s a look at the ranges:

• Normal: less than 120/80

• Prehypertension: 120-139/80-89

• Stage 1 high blood pressure: 140-159/90-99

• Stage 2 high blood pressure: 160 and above/100 and above

A single reading that’s out of the normal range does not automatically mean you have high blood pressure.

However, if your readings stay in a higher range over time, your doctor will want to discuss treatments, which likely will include lifestyle changes.

Dr. Qudsia Khan practices internal medicine for MultiCare Health System.