what is a normal blood pressure
The first number (e.g. 120) â systolic pressure â represents the pressure in your blood vessels (arteries, veins) when the heart contracts and pumps your blood. The second number (e.g. 80) â diastolic pressure â represents the pressure in your blood vessels between beats when the heart is at rest. Guidelines concerning blood pressure have changed in recent years. 120/80 (120 over 80) used to be considered normal. However, most doctors have now lowered the threshold to 115/75.