We all need blood pressure to live. Without it, blood can't flow through our bodies and carry oxygen to our vital organs. But when blood pressure gets too high — a condition called hypertension — it can lead to serious medical problems.
Hypertension is usually more of a problem for adults, but teens and kids also can have it. Even babies can have high blood pressure. The good news is that many of the things that cause hypertension can be treated.
Blood pressure is basically how hard your heart needs to pump to move blood around your body. It's the result of two different forces:
Blood pressure rises with each heartbeat and falls when your heart relaxes between beats, but there is always some pressure in the arteries.
Blood pressure can be affected by:
High blood pressure means a person's heart and arteries must work harder than they normally would. Over time, the added stress can damage them. When the heart and arteries don't work as well as they should, other body parts (like the kidneys, eyes, and brain) may suffer.
Having high blood pressure makes people more likely to have strokes, heart attacks, heart failure, kidney failure, or loss of vision.
People can have high blood pressure for years and not have any signs. In rare cases, severe high blood pressure can cause problems like these:
A person with high blood pressure who has any of these problems should see a doctor right away.
Blood pressure readings are fast and painless. Blood pressure is measured using an instrument called a (pronounced: sfig-mow-mah-NAH-meh-ter). This device has an inflatable cuff that a doctor or nurse wraps around your arm. As the cuff inflates, it squeezes an artery, stopping the blood flow for a moment. As the cuff deflates and the next heartbeat goes through the artery, the doctor or nurse measures the pressure. He or she also measures the pressure at its lowest point between heartbeats.
When doctors tell people their blood pressure, they use two numbers; for example, 120/80 ("120 over 80"). The first number is the systolic pressure. This is the pressure at the peak of each heartbeat. The second number is the diastolic pressure. This is the pressure when the heart rests between beats.
For adults (people 18 and older), blood pressure that's lower than 120 over 80 is normal. High blood pressure is 140 over 90 or higher. If someone's systolic pressure is 120 to 139, or if their diastolic pressure is 80 to 89, it's called prehypertension.
It's a little different for kids and teens: People younger than 18 have hypertension if 95% of kids or teens of the same age, height, and gender have lower blood pressure. Blood pressure between 90% and 95% of the normal range is considered prehypertension.
If a doctor or nurse thinks your blood pressure is too high, he or she will take at least three readings at different times before calling it hypertension. Teens with prehypertension or hypertension are more likely to have high blood pressure as adults.
Most of the time, there's no specific reason why someone has high blood pressure. This is called essential hypertension or primary hypertension. But some people have a medical condition that causes hypertension — like kidney disease or a thyroid disorder. This is called secondary hypertension.
If you have high blood pressure, a doctor might also check for high blood cholesterol and other conditions that could make heart disease or a stroke more likely.
Other causes of high blood pressure include:
A single reading showing high blood pressure doesn't mean that you have hypertension. It is a sign to watch your blood pressure, though. Sometimes, blood pressure needs to be checked several times over a period of days or weeks to determine if someone has hypertension.
Some people have what's called "white coat hypertension." This means that their blood pressure goes up when they're at a doctor's office because they're nervous. When they feel more relaxed, their blood pressure usually goes down. To make sure high blood pressure readings aren't caused by anxiety, doctors will sometimes track a person's blood pressure over a whole day. This is called ambulatory blood pressure monitoring.
If you have high blood pressure, your doctor will want to figure out why. He or she might ask about:
Your doctor will probably weigh and measure you. He or she might do urine tests or blood tests to check for other conditions that can cause hypertension.
Some people need medicine to control high blood pressure. Often, though, people can manage hypertension by making changes in their lives; for example:
If you've been told you have hypertension, your doctor will work with you to come up with a treatment plan.
In some cases, teens with severe hypertension may need to be careful about the kinds of exercise they do. Some will have to avoid things like weightlifting and bodybuilding until their blood pressure is back to normal.
Here are ways to help prevent hypertension and keep yourself healthy: