Low blood pressure is given the medical term “Hypotension” (as opposed to hypertension which is high blood pressure). Low blood pressure occurs when the pressure in the blood vessels falls below normal limits. Although different sources have different criteria for low blood pressure, we can assume that anything below 90/60 is low.

It is very difficult to define exactly what constitutes low blood pressure, since everyone is different. One person may suffer symptoms at 90/60 while another is totally fine at blood pressures which theoretically should have them on their back.

If you have no symptoms there is no reason for concern. Only when blood pressure drops below the level required by your body and cells, is there a real problem. When this happens, you get symptoms.

Symptoms of low blood pressure

• Dizziness
• Lightheadedness
• Fainting

Under severe low pressure, symptoms can include chest pains. Also, without the necessary pressure in the blood, the kidneys cannot filter out the toxins in your blood, and there will be an increase in blood levels of urea and creatine.

Causes of Low Blood Pressure

Low blood pressure can have a variety of causes including:

• Medication, including high blood pressure medicine, and medication for coronary heart disease.
• Anti-anxiety, and anti-depressant drugs.
• Diuretics
• Alcohol
• Dehydration – common when someone has diarrhea and-or vomiting. It is important to drink plenty of fluids (plain water works best) if you are ill with these.
• Slow heart beat
• Inflammation of organs in the body, e.g. acute pancreatitis
• Heart disease – when the walls of the heart become weakened and can no longer pump with the required force.

Should you consult a doctor?

Yes if:

• You lose consciousness when you stand up
• You constantly feel weak, light headed or tired.

Facts on low blood pressure

In younger people, low blood pressure can be a sign of chronic fatigue syndrome.

In older people, low blood pressure can indicate heart disease.

Young women (below 40) may find their blood pressure drops below 90/60 during:

• pregnancy
• hot weather
• dieting

Treatment for Low Blood Pressure

Since any treatment will depend on the cause of your low blood pressure, you must consult your doctor. It may be that some component of your lifestyle has caused the low blood pressure, and simple changes to that can restore your blood pressure to normal.

Unfortunately, there are often no symptoms of high blood pressure – which is why it is often called the “silent killer”.

You will often find out you suffer from high blood pressure (hypertension) on a routine visit to the doctor, or when going to see the doctor about another complaint (which may be as a direct result of your high blood pressure).

It is possible that you might suffer from headaches, nausea, dizziness or blurred vision, but many people will not even experience these symptoms.

High blood pressure puts your cardiovascular system under enormous strain, which can result in serious health problems, even death. High blood pressure is often responsible for heart attacks, strokes, and aneurysms.

When you suffer from high blood pressure, the capilliaries in your body can be easily damaged because of the pressure, meaning organs such as the eye and kidneys can be easily damaged.

How to tell if you have high blood pressure

There is only one way to be certain. Get it measured.

You can go to your doctor, or get a home blood pressure monitor and measure it yourself. Because of a syndrome called White Coat Syndrome, I personally prefer to measure mine myself.

There are various drugs and medications for high blood pressure treatment, though these can often have undesirable side-effects.

There are also natural ways you can reduce your blood pressure as well, including changing your diet, increasing exercise, giving up smoking and losing weight. In fact, I personally reduced my blood pressure to normal using a combination of these “natural methods”. You should also be aware that changes to your exercise and diet can be responsible for more than just lowering your blood pressure. Being more careful with the food you eat and doing a little more exercise can help reduce factors such as stress, heart disease, cholesterol, arthritis and prevent onset of diabetes.

Don’t risk being the next victim of the silent killer.

Blood pressure is a measure of the outward force exerted by the blood on the arteries in your body. A healthy body has a blood pressure that is just enough to push the blood into all of the smaller blood vessels of your body, called capillaries.

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.

Do you have high blood pressure at the doctors yet normal at home?

You may suffer from white coat syndrome.

A true story

I went to my doctor and was told I suffered hypertension. My blood pressure was 140/90. I was told I needed a lot of medical checks – weekly blood pressure readings, blood tests to check for cholesterol, thyroid problems etc, and urine tests, I guess to check for protein (which are normally not present in urine, but can be under extremes of pressure).

For my first weekly blood pressure check, I turned up on time for my appointment only to learn that she had gone off for lunch. Now, I am a patient man (no pun intended), but was not going to wait for her to return. I decided to go to the Pharmacy to get my blood pressure checked.

To my disappointment, my blood pressure was 140/100. The pharmacist asked if I was on medication. I was not, and did not want to be. I went home and did some research on the internet. I learnt about a phenomenon called white coat syndrome which made a lot of sense to me. The mere act of going to a doctor (white coat) made you nervous and increased blood pressure.

Well, the recommendation on the internet was to get a home blood pressure monitor. I bought one which had a cuff that went around the wrist, but found it inaccurate after checking at the pharmacy, so bought one that used an upper arm cuff. After getting it checked for accuracy at my doctors, I started taking my blood pressure at home on a daily basis.

To my amazement, my blood pressure during a typical day ranged from 130/90 to 110/65.

Certainly my blood pressure was not always high, and very rarely as high as it always seemed at the doctors office.

I now had it in my power to change my diet and monitor my blood pressure changes.

Giving up smoking cigars had a dramatic effect on my blood pressure. In addition, increased water intake to 3 litres or more a day, and decreased caffeine to 1 cup of coffee a day (I drank decaffeinated after this first one). Today, my blood pressure averages about 124/78. That’s normal.

Conclusions about white coat syndrome

Certainly my blood pressure at the doctors office was always higher than when measured at home. I have no doubt that white coat syndrome is a very real problem, and one I myself suffer from. I highly recommend you buy a home blood pressure monitor and check your blood pressure at home. Some doctors recommend this as a way of knowing your true blood pressure. Plus you can check what effects your lifestyle have on your blood pressure. This is the only way I have found to find an accurate measure of my blood pressure, while avoiding the elevating effects of white coat syndrome.

There is a suggestion that if you suffer white coat syndrome, it may indicate that your hypertension is linked with stress. Going to see the doctor stresses you and your blood pressure increases. If this is true, then just because white coat syndrome is responsible for your elevated blood pressure, it does not mean you are fine. You should continue checking your blood pressure at home, and also try to reduce stress levels in your daily life. Relaxation and meditation on a daily basis can help with this.

If you found this article about white coat syndrome interesting, you may be interested in learning more about diet changes that can help reduce your blood pressure.

Glossary of terms related to hypertension / high blood pressure.

Arterial Hypertension – also just called “hypertension”, refers to a condition where blood pressure is elevated above normal. Normal is usually quoted as below 120/80.

White coat syndrome – a condition where an individual has elevated blood pressure at the doctors office, yet has much reduced / normal blood pressure at home.

Hypertensive emergency – a severe hypertension that impairs proper functioning of the body’s organs. Requires medical treatment to aggressively lower blood pressure.

Exercise hypertension – is a rise in blood pressure in response to exercise. This does not affect everybody, and in healthy individuals, we would expect to see a small drop in blood pressure during exercise due to improved blood flow.

Malignant hypertension – chronic high blood pressure (> 240/120) resulting in organ damage, especially the eyes, kidneys, brain and lungs. Malignant hypertension is accompanied by swelling of the optic disk.

Pulmonary hypertension – is an increase in blood pressure in the pulmonary artery (carrying blood from the heart to the lungs) or vessels in the lungs. The right side of the heart is put under pressure, and one of the common symptoms is shortness of breath and chest pains during exercise.

Renovascular hypertension – also called “renal hypertension” refers to the kidneys. This is caused by a narrowing of the renal arteries (carrying blood to the kidneys), reducing blood flow to the kidneys, which respond by sending out signals to the body to raise blood pressure. Renal hypertension is a secondary form of hypertension (which just means that we know why it happens).

Systolic pressure – the peak pressure in your circulatory system when the heart contracts. When the heart beats, blood is forced out into the aorta, increasing the pressure.

Diastolic pressure – The lowest pressure in your circulatory system, which occurs during the resting stage of the cardiac cycle (heart is resting between beats).

The pressure of your blood depends on a number of factors including:

• the force created by your heart pumping blood into your arteries
• the volume of your blood
• the resistance your blood encounters as it moves through your blood vessels.

You body needs to make sure that there is sufficient pressure to push the blood into all of the capillaries around your body. Capillaries are the smallest blood vessels in your body, and ensure that all cells in your body receive nutrients they require to live.

Maintaining normal blood pressure is delicately balanced. Too high, and your heart and blood vessels are put under strain. Too low and the low blood pressure means some cells may not get the nutrients they require.

High blood pressure is often called the “Silent Killer” since there are often no symptoms. For this reason, it is important you get your blood pressure checked regularly.

Blood pressure readings can be taken by your doctor using a sphygmomanometer and stethoscope, or at home using a blood pressure monitor (the easiest ones to use are digital monitors). The home monitors generally come in two forms. One places a cuff around your wrist, while the other places a cuff around your upper arm (level with your heart). I personally have tried both types and found the most accurate one to be the upper arm cuff.

The blood pressure “numbers”

The blood pressure reading is two numbers. These are the two pressures of your blood at varying stages of your heart beat cycle:

The larger number is the systolic pressure, the lower number is the diastolic pressure.

Systolic pressure is the blood pressure being pumped into the aorta when the heart beats.

Diastolic pressure is the blood pressure in the arteries when the heart relaxes between beats.

Blood pressure does vary with age, sex and health, but in general, a healthy blood pressure is 120/80, or 120 over 80.

This means that systolic blood pressure is 120 mmHg, and the diastolic blood pressure is 80 mmHg.

Your blood pressure can actually tell a doctor a lot about the health of your heart and blood vessels. High blood pressure means that your heart is having to work harder to push your blood to all the cells in your body.

This can happen if e.g. you have narrowing of the arteries, since this narrowing increases the resistance of your blood vessels, and requires more pressure to get the blood through.

High blood pressure is also called hypertension, and can have serious consequences if not treated. e.g. high blood pressure can weaken the artery walls, and lead to rupture. If this happens in the brain, it can lead to a stroke.

There are a wide range of medicines and medications available to treat high blood pressure, and some alternative therapies such as acupuncture may also help, but you can also take immediate steps by looking at your diet and increasing your daily exercise (walking is a great exercise).

We explore some of the dietary considerations on this site, but please do consult a doctor before changing your diet or undertaking an exercise program.