Dr Michael Mosley: How beetroot can lower your blood pressure and even enhance your athletic ability
How this humble, purple vegetable can improve the health of your heart.
Last year I made a podcast series for BBC Radio 4 called Just One Thing, which was an unexpected hit. The idea is that each week I look at one thing you incorporate into your daily life which might have delightful, unexpected benefits. We ran a feature on this in BBC Science Focus, and the whole of series one and two (all 20 episodes) are available on BBC Sounds.
Well, I’ve got a new series which has just started and it kicks off with me making the case for consuming more beetroot, one of the few vegetables that lives up to claims of being a ‘superfood’. Beetroot gets its colour from betalains, powerful antioxidants that are present throughout the plant, but it is the high levels of nitrates that give beetroot its magic powers.
When we consume nitrate-rich vegetables such as beetroot, something remarkable happens. Bacteria that live in our mouths turn the nitrate into nitrite. The nitrite, in turn, is changed by the body into nitric oxide, which, among other things, increases blood flow to various organs, including the penis.
Adequate levels of nitric oxide are essential for producing and maintaining an erection, which may explain why the Romans used beetroot juice as an aphrodisiac. Although I haven’t yet seen any clinical trials showing that consuming beetroot juice will have a Viagra-like effect, there is evidence that the expansion of blood vessels it causes results in other significant changes.
A few years ago, we did an experiment on my BBC Two series, Trust Me, I’m A Doctor, where we took a group of volunteers with raised blood pressure and asked them to feast on a diet rich in beetroot. After a few weeks, we found that munching a couple of beetroot a day led to a fall in average blood pressure of about 5mmHg, which, if maintained, would translate into a reduction in their risk of stroke and heart attack of about 10 per cent.
The benefits of beetroot aren’t confined to helping those with raised blood pressure. There has also been a lot of research, much of it carried out by Andy Jones, a professor of applied physiology at the University of Exeter, showing that consuming beetroot – particularly in the form of concentrated juice – can enhance your athletic ability.
In one of his early studies, he asked a group of club-level competitive cyclists to compete in a couple of time trials, covering 16km, after drinking beetroot juice. What they didn’t know is that on one occasion they had normal beetroot juice, on another occasion the beetroot juice had the key ingredient, nitrate, removed. What happened? Well, the cyclists were, on average, 45 seconds faster when they were nitrate-powered, which in a competition would be massive. Beet that.
If you find the flavour of beetroot juice too strong and earthy, try flavouring it with apple, celery and a little ginger. And as for the vegetable, well you can incorporate it into risottos, burgers, bread and even cake (it goes well with chocolate).
- This article first appeared in issue 377 of BBC Science Focus Magazine – find out how to subscribe here
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