When your heart contracts, the pressure in your blood vessels goes up as the blood passes through. When your heart relaxes in between heartbeats, the pressure inside your blood vessels goes down. In order to push the blood to all your vital organs, you need healthy, elastic blood vessels that stretch and shrink as the pressure goes up and down.
In people with high blood pressure, the small blood vessels in the vital organs are most affected over time. These blood vessels become scarred, hardened, and less elastic, which means they are more likely to get blocked or rupture (leading to organ damage or even failure). This may happen as you get older, whether or not your blood pressure is too high. High blood pressure can speed up this process, so keeping it at a normal level is an important part of reducing the risk of:
Blood pressure changes frequently throughout the day. Factors that can make it change within just a few minutes include:
- Level of exercise
- Amount of tension
- Nicotine use.
It's easy to see why a person's blood pressure usually goes up and down within a certain range every day. Because of this, it's best to use more than one reading to determine your average blood pressure.
Blood pressure can also run high or low in families. It's important to look at your overall health, lifestyle, diet, and family history when comparing your number to what's considered "normal." These factors may cause you to have a higher or lower blood pressure reading than "normal."