Getting your blood pressure checked is a standard part of almost any visit to the doctor's office. And if you have high blood pressure, chances are you're monitoring your blood pressure at home, too. But what do those numbers really mean? Here's how to interpret your blood pressure numbers.

The Top Number: Systolic

The top number on your blood pressure reading is the systolic pressure, or the maximum pressure of the blood in your blood vessels when your heart is pumping. It is measured in millimeters of mercury, or "mm Hg." Generally, a systolic blood pressure of 120 mm Hg or lower is considered normal. If you have a systolic number greater than 140 mm Hg, you may have a type of high blood pressure called isolated systolic hypertension, even if your bottom number (diastolic) is normal. This type of hypertension can be a sign of a leaky heart valve, an overactive thyroid or some other underlying physical condition.

The Bottom Number: Diastolic

The other half of the blood pressure reading is the diastolic blood pressure, or the minimum pressure in your blood vessels when your heart is at rest. A diastolic pressure of 80 mm Hg or below is considered healthy for adults.

What The Total Number Means

In general, doctors consider normal adult blood pressure to be at or below 140/90 mm Hg. However, if you have diabetes, coronary artery disease or chronic kidney disease, your doctor may want to you maintain your blood pressure below 130/80. If your blood pressure is higher than 120/80 but not higher than 139/89, you are considered to have prehypertension, or are at risk to develop high blood pressure. Blood pressures over 140/90 are considered a sign of hypertension, and you doctor will normally recommend treatment. On the other hand, a systolic blood pressure of less than 90 or a diastolic pressure of less than 60 is considered too low, and may be a sign of heart or endocrine problems.

Source:

Blood pressure chart: What your reading means

AHA: Blood Pressure

NIH: What Is High Blood Pressure?

Resource:

Hypertension

Checking your blood pressure at home