What is Blood Pressure?
Take a Guess then Look Below

I have to admit that I didn't know the answer to what is blood pressure? I knew that 120/80 was like a make break point, but not much more than that. I'll show you what I learned.

Blood Pressure is one of the main vital signs showing how healthy the body is.

It is the pressure of the circulating blood on the walls of blood vessels. We usually measure the pressure in the arteries of the upper left arm.

The pressure is greatest near its source the heart. The farther from the heart the blood vessel, the less the pressure as a rule.

The normal blood pressure definition reads 90 to 120 for systolic (heart contracting) and 60 to 80 for diastolic (heart relaxing).

As of this writing, my blood pressure averages 138/74, which puts me in the prehypertension range. It's a far cry though from the 170/85 I use to have before starting my high blood pressure diet.

The following factors should be part of the blood pressure definition:

Resistance to blood flow - Resistance to the flow of blood comes from narrow blood vessels, length of the vessels and roughness of the interior walls of the vessels. Narrow long blood vessels with rough interior walls have the highest blood pressure.

The length of your blood vessels is genetic, so not much you can do about that.

Diet, supplements and blood pressure drugs target the width and smoothness of the vessels. They dilate the vessels and remove the fatty deposits that cause interior roughness.

Pumping rate - The more blood pumped per minute through the vessels the higher the blood pressure. The number of heart beats per minute doesn't necessarily mean higher pressure because the volume of blood per beat could be low.

Pumping rate isn't usually a factor that's treated.

Total volume of blood - The more blood in the system the faster the blood moves through the vessels. Excess salt can increase the volume of liquid in the body and cause higher blood pressure.

Dietary changes, cutting down on salt for example, or diuretic drugs are treatments for reducing blood volume and, hence, blood pressure.

Blood Thickness - Increased blood thickness (viscosity) increases blood pressure. That's why blood thinning drugs and natural remedies work to lower blood pressure.

Excess blood particles, blood cells for instance, increase viscosity. Excess sugar can cause an increase as well. Always try cutting down on sugar if you have high blood pressure.

Here we get more medical than I would like in explaining what is blood pressure.

Renin-angiotensin system (RAS) - Renin refers to the kidneys. When blood pressure or blood volume drops, the kidneys activate angiotensin II, a substance that causes blood vessels to constrict. This constriction raises blood pressure.

ACE inhibitors reduce the amount of angiotensin II produced. There are also drugs that target angiotensin II directly.

Aldosterone release - Aldosterone is a steroid hormone that is released by the adrenal glands in response to angiotensin II or high potassium levels. Aldosterone promotes sodium retention, and hence, water retention. Indirectly, this causes a increase in blood pressure.

Diuretic drugs counter this action by eliminating water from the body.

Baroreceptor reflex - In our necks are what are called baroreceptors. They send signals to the brain when blood pressure gets too high. The brain then signals the heart, blood vessels and kidneys to quickly lower blood pressure.

Currently, no drugs are available to target this system.

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