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High Blood Pressure Numbers


blood pressure monitor
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A reading of 120 over 80 falls in the normal range.

Blood pressure is expressed in millimeters of mercury, or mm Hg. High blood pressure is defined as a systolic blood pressure reading greater than 140 mm Hg or a diastolic blood pressure reading greater than 90 mm Hg. The systolic blood pressure is the top number of a blood pressure reading. This shows the maximum pressure in the blood vessels. Pressure is highest as the heart contracts and circulates blood throughout the body. The diastolic blood pressure is the bottom number of a blood pressure reading. It shows the lowest pressure in the blood vessels. Pressure is lowest between heartbeats, when the heart is at rest.

The National Institutes of Health has further defined high blood pressure. These categories are for people 18 years and older who do not take medication for high blood pressure and do not have a short-term serious illness.

 

 

 
 Systolic Pressure
 Diastolic Pressure
 Normal Less than 130
Less than 85
 High Normal
 130 to 139 85 to 89
 Stage 1 High Blood Pressure
140 to 159
 90 to 99
 Stage 2 High Blood Pressure
 160 to 179
 100 to 109
 Stage 3 High Blood Pressure
 180 or higher
 110 or higher
 

    For more information about high blood pressure, see the next page.


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