Blood pressure is created by a combination of factors in your body:

1. Force of the heart pushing blood out of the heart chambers into the aorta.
2. The volume of blood you have circulating in your circulatory system.
3. The size of the blood vessels that the blood has to travel through. As the diameter of the blood vessels decrease, it requires greater pressure to push blood through.

Your body has various systems in place to keep your blood pressure within very strict limits. Negative feedback systems are in operation. Sensors in your carotid artery and wall of the aorta monitor blood pressure, and if it gets too high, a signal is sent to the medulla in your brain, which in turn reduces your heart rate, and increases vasodilation (opening up) in blood vessels (called arterioles). This means the same volume of blood is distributed between more blood vessels, so overall blood pressure drops. When blood pressure drops, the opposite happens. Heart rate increases, and vasoconstriction (closing off) occurs in arterioles.

Things can and do go wrong

Various factors can cause high blood pressure (which is called hypertension by the medical community).

There are varying opinions on what measurements actually constitute high blood pressure, but the majority of source agree that:

Greater than 140 mmHg Systolic Pressure, and greater than 90 mmHg diastolic pressure is high. If you have two or more readings taken on different occasions, you may be diagnosed as having hypertension.

Symptoms & Signs of High Blood Pressure

Unfortunately high blood pressure has very few (if any) symptoms, and is often called the “Silent Killer”. You should go to your doctor and get your blood pressure checked frequently. Alternatively you could buy a personal digital blood pressure monitor and make the measurements at home. It could save your life.

What Causes of Hypertension

In most cases, the cause of hypertension is unknown. However, there are some factors which can contribute to it.

• Excessive alcohol
• Tobacco
• Obesity
• Salt in the diet
• genetic factors

Blood pressure can also increase in pregnancy, when the patient has kidney problems, or hormonal problems like an over-active thyroid, and even sleep apnea (a condition which causes the sufferer to stop breathing for a short time when asleep).

There are also some medications that can cause increased blood pressure including antacids, oral contraceptives, decongestants and diet pills. Please read the notes that come with any medication you are taking for details on possible blood pressure side-effects.

Risks of Hypertension

If your blood pressure is too high, your heart and arteries are put under stress, and can hate fatal consequences.

• Hypertension causes damage to the walls of your arteries causing them to become less elastic. This hardening of the arteries makes it much easier for harmful cholesterol to stick to your artery wall, reducing the diameter of the blood vessel through which blood must flow. With narrowing of the arteries, your heart must work much harder to push the blood through, and blood pressure rises. Possible consequences include heart attack, stroke, kidney failure, or even the amputation of the leg.
• Risks of heart attack and stroke are greatly increased in patients with high blood pressure.
• Heart enlarges which can cause heart attack.
• Bulging of the arteries outwards. These aneurysms can rupture, leading to blood spilling out into surrounding tissues. If this occurs in the brain, the patient will likely suffer a stroke.
• Blood vessels in the kidneys narrow possibly leading to renal failure.
• Blood vessels in the eyes can burst, causing a deterioration in sight, even blindness.

Treatment of high blood pressure

See our high blood pressure diet page to read about how you can reduce your blood pressure naturally. Also you can read about some of the medications used to treat high blood pressure, and possible side-effects of these drugs.

People who have high blood pressure need to watch what they eat. Closely linked to this is exercise, which is also beneficial. However, before changing diet or exercise routines, please consult your doctor to talk through your personal situation.

Causes of hypertension (high blood pressure) in most cases are very difficult to diagnose (in fact some sources suggest that even up to 90% of cases have unknown causes). However, some of the common factors thought to be involved include:

• moderate to excessive alcohol intake
• smoking
• too much caffeine
• being overweight
• too much salt in the diet
• genetics

These factors mean that:

• If you are overweight, try to lose weight. Reducing % body fat can lower blood pressure. A 30 minute walk every day can help you achieve this.
• Try to eat more fruits and vegetables and less processed foods.
• Always look at the nutritional information on the food you buy, and choose those low in salt (or sodium).
• Drink less caffeine drinks. Often fizzy drink contain a lot of caffeine, so do read those labels. Try to switch to decaffeinated coffee if you are a coffee drinker. I actually found I needed a caffeine coffee in the morning so had one caffeine coffee first thing, followed by decaf if I wanted more.
• Reduce alcohol intake to recommended levels or less.
• Stop smoking!

The problem with trying to lower your salt, is that there is so much hidden salt in the stuff you buy at the grocery shop.

Tips to reduce salt in your diet

• By products that are labeled as no salt added.
• By fresh meat and vegetables rather than processed products. Lots of those cold meats at the deli have added salt, as do canned vegetables.
• Try to stop putting salt on food when cooking or eating. You may find that the food becomes “tasteless” when you do this, but after a while you will get use to it.
• When buying bread, look for the sodium levels on the packaging and select the one with the lowest levels. I have found the amounts of sodium in sliced bread varies enormously.
• Cut back on stock cubes and packages soups which are often high in sodium. If you want stock cubes, look for low sodium ones.
• If using canned food, rinse well in water to remove salt. Tinned vegetables and tuna are good examples of foods packages in extra salt.
• Read the labels on breakfast cereals. These often have high levels of salt.

Additional Supplements thought to contribute to lowering blood pressure

Magnesium, potassium and calcium are three very important elements of a diet, and are thought to have blood pressure lowering properties. I have listed below some of the sources of these supplements, but please do consult your doctor before supplementing with these minerals.

Magnesium – dark green leafy vegetables. Soy products, legumes and seeds, nuts (e.g. almonds and cashews), whole grains like brown rice, bananas, dried apricots, and avocados. Your body eliminates excess magnesium.

Potassium – salmon, cod, and sardines. Broccoli, spinach, lettuce, parsley, peas, lima beans, tomatoes, potatoes with skins. Citrus fruits, apples, bananas, and dried apricots. Note people with kidney problems should avoid these foods. They require a low potassium diet.

Calcium – Milk and dairy products such as yogurt and cheeses. However, try to go with low fat products. Skimmed milk has a higher calcium content than full fat milk. Broccoli, kale, and bok choy. Salmon and tinned sardines (eat the bones), shellfish, almonds and Brazil nuts. Also look for products with extra added calcium.

B Vitamins – Broccoli, spinach, wheat germ, bananas, potatoes, chicken, fish, lean meat, milk, liver and eggs.

Omega 3 – Walnuts, oregano, salmon, halibut, shrimps, cod, tuna, scallops, cauliflower, cabbage, broccoli, sprouts, kale, spinach and strawberries. Look out for margarine and dairy drinks with added Omega 3.

The DASH Diet

The DASH Diet puts many of these factors into an easy to follow diet system. You can get a free copy of the Dash Diet from the National Heart, Lung and Blood Institute website. The DASH diet is clinically proven to significantly reduce blood pressure.