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High blood pressure

By Shaun Holt

Hypertension (high blood pressure or HBP) is a common condition in which the force of blood pushing against the walls of the arteries is high.

If this pressure rises and stays high, over time, it can damage the artery walls and this will likely cause health problems in the future. The main ones are:

Cardiovascular disease i.e. heart attack or stroke - HBP causes hardening and thickening of the arteries (atherosclerosis).

Aneurysms - the HBP can cause arteries to weaken and bulge (an aneurysm), which can be fatal if they rupture.

Heart failure - often confused with a heart attack or cardiac arrest, this is when heart muscle thickens due to the HBP and may not be able to pump enough blood.

Kidney damage - due to weakened and narrowed blood vessels in the kidneys.

Eye damage - which can result in blindness.

Metabolic syndrome - disorders including increased waist circumference, cholesterol levels and insulin levels.

Memory problems - if the arteries in the brain are affected.

The above serious health problems soon become evident, but in the early stages, often for years, people can have HBP without any symptoms. But what causes it in the first place? Usually there is no identifiable cause of the raised blood pressure (BP) - this type is called essential hypertension or primary hypertension and develops gradually over several years.

If the HBP is caused by an underlying condition, this is secondary hypertension. This type can appear much quicker and the rise in BP tends to be greater. Causes include kidney disease, thyroid disease and medications such as birth control pills, cold remedies and over-the-counter pain relievers.

It is strongly recommended that a person with raised BP makes certain lifestyle changes if this is contributing to the problem i.e. reduce stress, reduce salt in the diet, lose weight, stop smoking and reduce alcohol intake.

The natural products that are most often taken to reduce BP are:

Coenzyme Q10

CoQ10 is a potent antioxidant and also a cofactor in many metabolic pathways. It is very effective for reducing HBP but this is not widely known amongst healthcare professionals. Combined with the lack of significant side effects, cardiologists are increasingly starting to recommend CoQ10 as an adjunct or alternative to conventional medicines.

Fish oil

It is well known that fish oil can reduce cholesterol levels, but the antihypertensive effect of fish oil is not as well known. And secondly, while the results were statistically significant, the reduction in BP was modest. As many people with HBP will also have raised cholesterol levels, any consequential reduction in BP from the fish oil is an added bonus, though it is probably not sufficient reason by itself to take this supplement for HBP.


Calcium supplementation may lead to a small reduction in systolic but not diastolic BP. Given the very small benefit in terms of a BP reduction, calcium supplements are not recommended for BP control, although there may be other good reasons to take them.


Supplementation with magnesium also lowers BP by a small extent. The doses of magnesium used in the studies ranged from around 250 to 1,000 mg/day and higher doses appeared to have a greater effect.

What do the blood pressure numbers mean?

The first or top number ‘systolic’ is the pressure in the arteries when your heart pushes blood through the arteries. Normal is below 120, borderline is between 120 and 140, over 140 is considered high.

The second or bottom number ‘diastolic’ is the pressure in the arteries when the heart rests between beats. Normal is below 80, borderline is between 80 and 89, over 90 is considered high.