President Fords historic trip and fall down the steps of Air Force One. 1  People & Blogs. 2  Standard YouTube License.
The bottom number, called the diastolic pressure, is the measurement as the heart relaxes between beats. Normal blood pressure is a systolic pressure of less than 120 millimeters of mercury (mm Hg) and a diastolic pressure of less than 80 mm Hg, or 120/80 mm Hg, according to the American Heart Association (AHA). Having a blood pressure greater than 140/90 mm Hg is considered high blood pressure or hypertension. A blood pressure level between normal and hypertension, is called prehypertension, meaning it is higher than normal, but not high enough to be considered hypertension.
Low blood pressure is usually not dangerous for healthy people. A blood pressure reading states the systolic pressure first, followed by the diastolic pressure. Normal blood pressure, according to the American Heart Association, is pressure lower than 120/80. Low blood pressure occurs when the systolic pressure is below 90, or when the diastolic pressure is below 60.