What is high blood pressure?
Blood pressure (BP) is the force exerted by the heart and arteries to keep the blood flowing through your body. Your blood pressure is raised when that force is excessive. Most people will experience short bursts of elevated blood pressure at times. This is normal and may be caused by stress, anxiety, excitement and exertion. In fact, one needs an increase in blood pressure to jump away from a speeding car, for example.

Persistent levels of elevated blood pressure are detrimental to your health. High blood pressure makes your heart work harder, straining it abnormally. The heart eventually becomes enlarged and overworked and loses its ability to pump blood properly, leading to heart failure. High blood pressure also damages the lining of your arteries, leading to heart attacks, kidney disease and strokes.

How is high blood pressure measured?
Blood pressure is always measured with a top and bottom figure. The top figure, called the systolic pressure, represents the pressure during the phase of systole, meaning the maximum pressure exerted by the heart when it contracts. The bottom figure, or diastolic pressure, is the pressure exerted during the phase of diastole, when the heart is totally relaxed and being filled with blood. The pressure is therefore an indication of the force exerted by the arteries, which are continuously squeezing the column of blood because of their elastic nature.

What role does diet and lifestyle play in causing high blood pressure?
The excessive intake of salt causes an impairment of the body’s blood pressure regulating mechanisms. Smoking, lack of exercise and being overweight also lead to high blood pressure. Stress is an aggravating factor and excess alcohol and coffee intake may also contribute.

Because sodium, a component of salt, plays a major role in blood pressure regulation you should attempt to restrict your sodium intake. Although normal table salt is our major source of dietary sodium, sodium is not always found in salt form. This means that you cannot always rely on taste to judge how much sodium food contains, as high sodium foods like instant puddings do not necessarily taste salty. It is also found in ingredients like mono sodium glutamate, baking powder and sodium bicarbonate. All food in its natural state contains sodium. Processed foods, however, are much higher in sodium content, as sodium is almost always added to preserve taste and maintain freshness.

To sustain our body’s basic biochemical functions we need only about 50 mg of sodium per day. Most people, however, consume between 4000 and 7000 mg of sodium per day. When we look at the following examples, it becomes obvious why our diets are so high in sodium content. (Notice how food processing increases sodium levels.)

• Chicken breast, unsalted = 126 mg versus chicken noodle soup, canned, 1 cup = 1107 mg
• Tomato, 1 medium fresh = 11 mg versus tomato juice, 1 glass = 658 mg

What can I do to lower my blood pressure?

Step 1
Stop adding salt to your food.

Step 2
Avoid pre-prepared, canned and processed food as much as you can.

Step 3
Choose low sodium equivalents of products such as baked beans, baking powder, margarine and stock powders by reading food labels. Look for words like ‘no added salt’, ‘low salt’ or ‘reduced salt’.

Step 4
Avoid eating bland, boring food by using alternative flavours like lemon juice, flavoured vinegars, herbs and spices. Use fresh or dried herbs and spices in preference to packaged seasoning mixes, as most dried herb, garlic and onion powder mixes contain MSG (monosodium glutamate). Mustard, relish, chilli sauce and soya sauce are, unfortunately, also high in sodium content, and quantities must be kept small. (Low sodium versions can be obtained.)

Step 5
Take blood pressure medication. Your doctor will assist you in this regard, and if you are already taking prescription medication, stay on it.