In simplistic terms, blood pressure is a measure of the force with which your blood is pumped round your body. It is the pressure that your pumping blood places on the walls of your arteries, the blood vessels that carry blood away from your heart. The easiest way of understanding the concept of BP is to think of water pumping through a garden hose. When it does so, the water places pressure on the walls of the hose as it tries to 'escape' in any possible direction.

And in the same way that you increase the pressure on the walls of your garden hose if you increase the water flow by turning the water tap or faucet on a little more, your increases if your heart starts pumping more blood around your body for some reason in exactly the same way.

Your exact hypertension is measured by reference to two different factors. The first of these factors is the strength of each heartbeat, while the second is the resistance put up by the 'tubes' through which you blood passes, primarily your capillaries and arms.

It is the arterioles, the tiny blood vessels that feed into the capillary network that regulate hypertension more than any other part of your body. These arterioles expand and contract in rhythm with the beating of your heart as result of the muscular tissue in their walls. Here, measuring hypertension is in effect checking the strength or weakness of your heart.

Your blood pressure is measured by reference to two differentumbers which represent the systolic and diastolic pressures.

The first of these, the systolic is a measurement of the highest pressure point which is recorded when the heart beats or contracts. The lower figure, the diastolic is a measure of what is happening when your heart is at rest, effectively representing the low point of your blood pressure.

As a general rule, it is the diastolic pressure measurement which medical professionals pay most attention to, because if your diastolic pressure is too high, it suggests that your arms and capillaries are under too much pressure even when your heart is at rest.

In an average non stressed adult, normal hypertension would be in the region of 120/80 mmHg. In fact, the better your physical condition, the lower your diastolic pressure measurement is likely to be, with well condition athletes regularly recording a diastolic pressure of between 50 and 60 mmHg.

However, according to the American Heart Association, nearly 1 in three adults in the USA sufferers from high blood pressure.

Much more terrifyingly, it is believed that anything from one third to one half of high blood pressure sufferers are completely unaware of their condition, which is one reason why your doctor always measures your blood pressure when you visit them irresistive of the condition that has bought you to their office or surgery in the first place.

High blood pressure is known by the medical profession as hypertension, but it is also possible to suffer from a slightly less serious form of the condition known as pre-hypertension as well.

Although exact definitions of what represent high blood pressure variants to a certain degree from country to country, the National Heart, Lung and Blood Institute suggests that in the USA, systolic pressure of between 120 and 139 or a diastolic pressure of between 80 and 89 mmHg representations pre-hypertension.

Stage one hypertension is represented by systolic pressure of between 140 and 159 or diastolic pressure in the range of 90 to 99 mmHg, while stage two hypertension is demonstrated by a reading in excess of 160/100 mmHg.

Why does it matter?

As suggested earlier, there are huge numbers of people in the USA (and in most industrialized Western countries) who suffer from high blood pressure that are not even aware of their condition.

This is the primary reason why high blood pressure is often known as 'the silent killer' as many of the conditions to which high blood pressure contributions are often fatal. In effect, if you have high blood pressure condition that you are not aware of, you are more likely at risk of suffering a wide variety of potentially lethal medical conditions without being in a position to take steps or measures to reduce the risk, hence, the 'silent killer' soubriquet.