A blood pressure (BP) reading consists of two numbers: systolic vs. diastolic pressure.
Both numbers give important information about your health.
However, your healthcare provider might give more importance to high systolic pressure to determine your risk ofheart disease.
Illustration by Joules Garcia for Verywell Health
However, it is not a steady stream like you might see from a garden hose.
The pulse of the blood flow and the pressure it exerts change from moment to moment.
It’s highest during the heartbeat (systolic pressure) and lowest between heartbeats (diastolic pressure).
Providers measureblood pressureusing these numbers because it is a standard way of describing the force of the pulsing blood.
Which Is More Important: Diastolic or Systolic Blood Pressure?
Your systolic and diastolic blood pressures are both important.
Systolic Blood Pressure
During a heartbeat, the heart pushes blood out into the arteries.
Systolic pressure is the measure of this pressure within the arteries while the heart beats.
This phase, known as systole, is the point at which blood pressure is the highest.
Systolic pressure below 90 mmHg is considered low and may require intervention and management from your healthcare provider.
The systolic pressure goes up with it.
In these cases, the increased pressure is normal.
Is 140 Over 70 a Good Blood Pressure Reading?
Normal blood pressure for an adult is 120/80 mmHg or lower.
A systolic blood pressure of 140 mmHg is considered high and signifies stage 2 hypertension.
Low Systolic Blood Pressure
Systolic pressure can also be too low.
When the reading is below 90 mmHg, it’s calledhypotension.
This can cause lightheadedness,dizziness, orfainting.
If low blood pressure is not treated, it may cause organs like the kidneys to start shutting down.
Systolic hypotension can occur if the amount of blood in your body becomes too low.
For example, low blood pressure can happen when you are severely dehydrated or when you have major bleeding.
In these cases, there just isn’t enough blood to push through the body.
Sometimes, low blood pressure happens when you change positions suddenly.
You may feel dizzy when you stand up because gravity is pulling blood down toward your feet.
This is a common condition calledorthostatic hypotension.
Diastolic Blood Pressure
The heart rests between beats so it can refill with blood.
The pause between beats is called “diastole.”
Your diastolic blood pressure is the measurement during this pause before the next heartbeat.
If you receive multiple readings with these numbers, you should call your healthcare provider.
Your healthcare provider might suggest you take your blood pressure at home.
What Time of Day Should I Check My Blood Pressure?
In addition, your blood pressure will be different throughout the day.
It tends to be highest in the morning and lower at night.
take a stab at avoid taking it right when you wake up in the morning or right after dinner.
Once you decide what time you’ll check your blood pressure, it’s important to be consistent.
Both of these values are important for diagnosing and managing high blood pressure.
It’s important to get an accurate blood pressure reading under calm, quiet conditions.
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