What is blood pressure?

Your Heart: The Hardest-Working Muscle

You have an incredible heart. No, seriously. Your heart is a tireless muscle with one job: to keep you alive by pumping blood to every inch of your body, all day, every day, without a break.

This is no small task because blood is essential for your body to function. Your eyes need it to see, your muscles need it to move, and your skin needs it to glow. Blood powers everything—it lets you think, feel, taste, and live. Without it, you’d die.

Your heart does this by alternating between two actions:

• Relaxation phase: It relaxes to let blood flow in, like a sponge soaking up water.
• Contraction phase: It squeezes to push blood out into your arteries, sending it to all the places it’s needed.

This relax-and-contract cycle repeats about 100,000 times a day, and with each squeeze, your heart creates the pressure needed to move blood through your body. Why is this so important? Because blood can’t move on its own—it relies entirely on your heart to push it along. Every single heartbeat creates that push, and that push is what we call blood pressure.

Now your heart doesn’t work alone—it needs arteries to deliver blood throughout your body.

Arteries: The Highways for Blood

Your arteries are the tubes that carry blood from your heart to the rest of your body. Think of them like highways for blood.

• Big arteries are like major highways, moving large amounts of blood to places like your arms, legs, kidneys, and brain.
• Small arteries are more like back roads, branching off to reach tiny places like your fingertips, toes, and eyes.

Arteries come in all sizes—some as wide as your thumb, others so tiny you’d need a microscope to see them. They’re strong and flexible, built to handle the pressure of blood flowing through them.

You can probably tell by now that I’m a big fan of analogies, and here’s one of my favorites: your heart is like a faucet, turning on to send water through a garden hose. The water is your blood, the hose is your arteries, and the garden is your body. Just like a garden needs water to bloom, your body needs blood to stay alive and thriving.

But here’s the key: the pressure in the hose needs to be just right. Too much pressure can damage the hose, while too little pressure means the water won’t reach all the plants. So then, what happens when the pressure in our arteries is too high?

High Blood Pressure is a Big Deal

Healthy arteries are smooth and flexible, built to handle the flow of blood with ease. But high blood pressure changes that. Over time, it can damage your arteries, making them stiff or clogged.

Think back to the garden hose. If it gets stiff or clogged, water struggles to get through. The same thing happens in your arteries. When this happens, your heart has to pump harder to push blood through, which raises blood pressure and stresses your arteries.

The consequences can be serious. Since arteries are found all over your body, damage in one area affects the organs they supply. For example:

• In the brain, damaged arteries can cause a stroke.
• Near the heart, they can cause a heart attack.
• In the kidneys, they can lead to kidney disease.
• In the eyes, they can lead to blindness.

High blood pressure isn’t just a threat to your heart—it’s a threat to your entire body.

Why Does High Blood Pressure Happen?

High blood pressure happens when your heart is working too hard or your arteries aren’t in great shape. Here are the usual suspects:

1. Stress
   Stress releases adrenaline and cortisol, which make your heart pump harder and faster. It’s useful if you find yourself running from a bear, but not so much for everyday life.
2. Eating Too Much Salt
   Salt attracts water. The more salt you eat, the more water your body holds. And the more water in the hose means more pressure.
3. Being Inactive
   Your heart is a muscle. Like any muscle, it gets weaker if you don’t use it. Regular exercise helps your heart stay strong and pump efficiently.
4. Being Overweight
   Believe it or not, body fat needs blood too. The more weight you carry, the more places your heart has to send blood to. It’s like asking a delivery driver to handle twice as many stops without extra help.
5. Getting Older
   Aging causes arteries to lose flexibility, and the heart to become weaker. While we can’t stop aging, healthy habits like eating well and staying active can slow this process.

So, What is Blood Pressure?

In the simplest terms, blood pressure is the force of your blood pushing against the walls of your arteries.

We measure it because it tells us how hard your heart is working. If blood pressure is high all the time, your blood is pushing too hard against your arteries, which can damage them over time.

It’s like leaving a garden hose running on full blast—the constant pressure eventually wears down the hose. Keeping your blood pressure in a healthy range doesn’t just protect your heart—it’s the key to keeping your body running smoothly and living your healthiest life.

Woah, didn’t expect to see you all the way at the end. If you finally understood what blood pressure is, then you’re in the right place! Check out the companion article, What is Cholesterol?