Known as the 'silent killer', high blood pressure is a force to be feared. When pressure inside the blood vessels is high over a period of time, it increases the risk of stroke and heart disease. It can cause kidney damage, hardening of the arteries and even blindness.

As many as 10 million Britons and 75 million Americans are living with high blood pressure, also called hypertension. Many experience no symptoms, and don't even realise they are at risk until some damage to their health is already done.

So what has a humble, red root vegetable to do with the health of our blood vessels? Since ancient times beetroot has been used medicinally as a tonic and to boost immunity, and now research indicates that the deep red juice of the beetroot is a natural treatment for hypertension. A 2008 study conducted by scientists at the London Medical School found that drinking 500ml (20oz) of beetroot juice (the equivalent of eating 5 medium beetroots) caused a significant drop in blood pressure that was still noticeable 24 hours later. The reason for this remarkable fact is that beetroot contains high levels of nitrates, including nitric oxide, a chemical naturally produced by our blood vessels to relax the vessel walls and keep blood pressure low. Beetroot juice increases this effect. As a further benefit, nitrates also help prevent blood clots and protect the lining of the vessels.

Yet despite beetroot's good publicity - the 2008 research was published in the Journal of the American Heart Association, and reported widely in the press - beetroot juice drinkers are still in the minority. Could it be a matter of flavour?

Often described as 'earthy', perhaps beetroot juice is an acquired taste, but there is no need to take it neat, it can be mixed with any other juice to make it more palatable. And a little 'earthiness' is surely preferable to the potential side effects of the most commonly prescribed blood pressure medications, which may include muscle weakness, fatigue, nausea, persistent cough, dizziness, headache, nightmares and impotence. The only side effect of beetroot juice you may notice is that your urine turns pink as the natural red pigment passes harmlessly through your system. Given the choice, I would say 'pass the beetroot'!

I must make an important point here; if you are already taking blood pressure medication prescribed by your doctor, you should on no account stop taking it without consultation. Similarly, if you have concerns that your blood pressure is high, do seek medical advice. Beetroot juice may well enable you to reduce or stop your medication, but you must do this only with your doctor's support.

Having made this proviso, there is still every reason to trust the beetroot.

Just 500ml (20oz) of beetroot juice a day will help lower your high blood pressure. It will help prevent an increase in blood pressure, important for those approaching middle age when bp naturally rises. It will boost your immune system and your heart health. It will even help improve your athletic performance - you can exercise longer before tiring after drinking the juice because it increases your body's oxygen uptake.

The humble beetroot is everyone's friend, from hypertensives to athletes, and those of us who just need a little more everyday stamina.

Try it. Swap your morning OJ for a BJ, or mix the two (an OBJ?), and reap the many benefits of beetroot.