High blood pressure—hypertension—refers to blood pushing against the walls of the arteries with chronically elevated force. Blood pressure that rises above normal levels and remains high can lead to serious health problems including heart attack, heart failure, stroke, and kidney failure.
Blood pressure is measured in millimeters of mercury (mmHg). The top number, known as the systolic pressure, represents the pressure within the arteries when the heart contracts while pumping blood. The bottom number, diastolic pressure, represents the pressure in the arteries when the heart relaxes between beats and fills with blood.
Normal blood pressure is defined as less than 120 over less than 80. A person whose blood pressure runs between 120–129 over less than 80 is said to have elevated blood pressure, a classification that is used to further encourage taking preventive diet and lifestyle measures. Stage 1 hypertension is diagnosed for those with systolic numbers between 130 and 139 OR diastolic numbers between 80 and 89. Systolic numbers that are 140 or over OR diastolic at 90 or over is considered Stage 2 hypertension, which is a serious risk factor for stroke and other cardiovascular events….