Blood is carried from the heart to all parts of your body in vessels called arteries. What is Hypertension . Blood pressure is the force of the blood pushing against the walls of the arteries. Each time the heart beats (about 60-70 times a minute at rest), it pumps out blood into the arteries. Your blood pressure is at its highest when the heart contracts. This is called systolic pressure. When the heart is at rest or relaxes, between beats, your blood pressure falls. This is the diastolic pressure. It’s measured in millimeters of mercury (mm Hg). High blood pressure (or hypertension) is defined in an adult as a blood pressure greater than or equal to 140 mm Hg systolic pressure or greater than or equal to 90 mm Hg diastolic pressure.

Blood pressure is always given as these two numbers, the systolic and diastolic pressures. Both are important. Usually they are written one above or before the other, such as 120/80 mmHg. The top number is the systolic and the bottom the diastolic. When the two measurements are written down, the systolic pressure is the first or top number, and the diastolic pressure is the second or bottom number (for example, 120/80). If your blood pressure is 120/80, you say that it is “120 over 80.”

High blood pressure can occur in children or adults, but it’s more common among people over age 35. It’s particularly prevalent in African Americans, middle-aged and elderly people, obese people, heavy drinkers and women who are taking birth control pills. People with diabetes mellitus, gout or kidney disease are more likely to have high blood pressure, too.

American Heart Association recommended blood pressure levels