Your Blood Pressure Explained

Blood pressure is the pressure causing the blood to flow through a person's body from areas of high pressure (the arteries), through the body organs and into areas of low pressure (the veins). 

Blood pressure readings are shown as two numbers, in the form systolic/diastolic blood pressure, ie 120/80.

Where
Systolic = the pressure in the arteries as the heart contracts and pumps blood into the arteries.
Diastolic = the pressure in the arteries as the heart relaxes after contraction.

More often than not, systolic blood pressure tends to be between 90 and 120 millimetres of mercury (mm Hg) for most healthy adults. Normal diastolic blood pressure falls between 60 and 80 mm Hg.

Low blood pressure which is also known as hypotension is blood pressure so low it causes physical symptoms due to the very slow flow of blood through the veins and arteries. 

As a result of this, the vital organs do not receive enough oxygen and nutrients and run a real risk of becoming damaged (sometimes irreparably) and they cease to function properly.

Common symptoms of low blood pressure are dizzy spells, fainting, feeling light-headed and nauseous. Often, these symptoms tend to be more apparent when a person is lying or sitting and then they suddenly stand up. 

Low blood pressure in itself it not a terrible thing.  As long as it is not low enough to cause problems and damage to the vital body organs, then low blood pressure is advantageous because people with lower blood pressure are less likely to suffer from heart disease, renal (kidney disease) and are at a lower risk of strokes. 

Unlike high blood pressure, which is defined on the foundation of the blood pressure reading alone, low blood pressure is categorised primarily by symptoms of low sluggish blood flow.

Some people may have a blood pressure reading of 90/50 yet exhibit no signs or symptoms of low blood pressure (fainting, dizziness, light-headedness, because they don't show any problems these persons are not defined as having a  low blood pressure. 

However there may be other people who have a blood pressure reading of 130/80 and may exhibit the symptoms of low blood pressure if their blood pressure reading drops to 100/60. It literally depends on the person and what is classed as a "normal" blood pressure reading for them.