Hypertension: the Science and Your Health
What is blood pressure? What are the effects of high blood pressure?
Blood pressure is the pressure on the walls of your arteries when your heart beats.
We measure two numbers when checking blood pressure. The top number/systolic is higher because it is measured when the heart is contracting/ beating. The bottom number/diastolic is lower because this is when the heart is relaxing/ between beats.
The arteries carry oxygen and other nutrients from the heart to the rest of our body. We want these blood vessels to be as healthy as possible.
With high blood pressure:
Your blood vessels can become damaged (due to the high pressure system).
Your heart has to work harder (because it is pumping against a high pressure system).
Your organs can also become injured (blood arrives at too high of a pressure).
**Think about water pressure and the damage that can occur in plumbing systems when the pressure is too high. This is the same concept.
What causes high blood pressure? How does it affect my health?
Mechanical causes of high blood pressure:
If your artery walls are more rigid/less flexible, they don’t easily expand when your heart beats. This causes the inner width/diameter of the artery to be smaller, which causes your blood pressure to be higher. This is a natural consequence of aging as the arteries calcify.
If your blood is too thick due to excess fat and/or high sugar levels, this will also increase your blood pressure. Obesity and diabetes increase your risk of high blood pressure.
-HEART DAMAGE-
When your blood pressure is high, your heart has to work harder to pump blood to your organs. Eventually this can cause heart problems. When the heart has to work harder, the size of the heart muscle increases- this is not a muscle that we want to get bigger. A thicker/larger heart muscle does not pump as effectively. This can lead to heart failure and other problems.
-ARTERY DAMAGE-
High blood pressure damages the walls of your arteries. This can cause weakening in the walls, which increases the risk of them expanding or ballooning out in a specific area- to try to relieve the increased pressure. This is an aneurysm.
High blood pressure also nicks the inner walls of your blood vessels. Your body uses cholesterol, fat, and calcium to form patches/plaques to repair these nicks in the walls of your blood vessels.
These plaques can decrease blood flow within the arteries, leading to higher blood pressure. These plaques also increase your risk of stroke and heart attack.
-ORGAN DAMAGE-
When your blood pressure is high, your organs are receiving blood flow at a higher pressure and this causes damage, such as kidney disease and eye problems.
How does exercise, a low salt diet, and stress reduction lower blood pressure?
Exercise increases the flexibility of your arteries. Having more flexible/less rigid arteries reduces blood pressure.
With a high salt diet, your body holds on to fluid. If you reduce the salt in your diet, your body will get rid of this fluid. Having less fluid in your blood vessels reduces blood pressure.
With high stress levels, your sympathetic nervous system (fight/flight) is activated. This increases levels of stress hormones (adrenaline, cortisol). These hormones work to increase your blood pressure and heart rate. With stress relief, you activate your parasympathetic nervous system (rest/relax). This lowers your blood pressure and heart rate.