Blood pressure is the force of blood against the walls of arteries as it circulates through the body. It is typically measured using two numbers: systolic blood pressure and diastolic blood pressure. Systolic blood pressure is the pressure in the arteries when the heart beats and pumps blood out, while diastolic blood pressure is the pressure in the arteries when the heart is at rest between beats. Blood pressure is measured in millimeters of mercury (mmHg) and is typically expressed as systolic pressure over diastolic pressure (e.g. 120/80 mmHg).
High blood pressure, or hypertension, occurs when the force of blood against the artery walls is consistently too high. This can strain the heart and blood vessels, increasing the risk of heart disease, stroke, and other health problems. Regular blood pressure readings typically fall below 120/80 mmHg. Treatment for high blood pressure may involve lifestyle changes such as diet, exercise, and medications.