What is High Blood Pressure?

Doctor reviewing lab work with patient at her desk

High blood pressure is also known as hypertension. It happens when the force of your blood pushing against the walls of your blood vessels is too high. High blood pressure can lead to other serious problems such as heart attack and stroke.

Watch video: Is there a difference between hypertension and high blood pressure?

Know your numbers.

Nearly half of U.S. adults have high blood pressure. Many don’t even know they have it. The only way to know you have high blood pressure is to have your blood pressure checked. A diagnosis of high blood pressure will need to be made by a health care professional.   

Learn about your blood pressure numbers and what they mean.

BLOOD PRESSURE CATEGORY SYSTOLIC mm Hg (upper number) and/or DIASTOLIC mm Hg (lower number)
NORMAL LESS THAN 120 and LESS THAN 80
ELEVATED 120 – 129 and LESS THAN 80
HIGH BLOOD PRESSURE (HYPERTENSION) STAGE 1 130 – 139 or 80 – 89
HIGH BLOOD PRESSURE (HYPERTENSION) STAGE 2 140 OR HIGHER or 90 OR HIGHER
HYPERTENSIVE CRISIS (consult your doctor immediately) HIGHER THAN 180 and/or HIGHER THAN 120

Blood pressure and the circulatory system

Your tissues and organs need the blood your circulatory system carries through the body. Your heartbeat makes this happen by pushing blood through the blood vessels. These vessels include arteries, veins and capillaries.

Blood pressure is the result of two forces. The first force (systolic pressure) happens as blood pumps out of the heart and into the arteries. The second force (diastolic pressure) is created as the heart rests between heart beats. These two forces are each represented by numbers in a blood pressure reading.

The damage starts in your arteries and heart.

See how HBP damages heart

See how high blood pressure can damage your arteries and heart.

When blood pressure is high for too long, it can damage the walls of blood vessels, causing them to develop tiny tears. To fix these damaged areas, the body sends special cells that stick to the site. Over time, substances such as cholesterol and fats may also build up at these damaged spots, forming plaque.

As plaque slowly builds, a process called atherosclerosisit can make the inside of the arteries narrower. This narrowing can block the flow of blood, further increasing blood pressure. 

Health threats diagram

 High blood pressure is a 'silent killer.'

Preventing and managing high blood pressure

  • It’s best to avoid high blood pressure altogether. Healthy lifestyle choices such as not smoking, eating a healthy diet and being physically active can help. 
  • If you have high blood pressure, work with your health care professional to control it. This may mean taking medications in addition to making healthy lifestyle changes.

Controlling your blood pressure will help you live a longer, healthier life.

Get the high blood pressure fact sheet: English (PDF) | Spanish (PDF)

Video: 130 Is Too High For Blood Pressure