A daily dose of tomato could significantly improve the functioning of blood vessels in patients with heart disease, research suggests.
A study has found that a powerful antioxidant in tomatoes may contribute to the health benefits of a Mediterranean diet.
Participants in the study were given a pill containing a supplement called Ateronon that contains seven milligrams of the tomato ingredient lycopene. Lycopene is 10 times more potent than vitamin E and previous research showed its potency appears to be enhanced when it is consumed pureed, in ketchup or in the presence of olive oil.
But why it had this effect was unknown, so scientists at the University of Cambridge and the Cambridge University Hospitals NHS Trust set out to explore one mechanism by which they believe lycopene reduces the risk.
Of 36 patients with heart disease, those taking the pill every day for two months saw their blood vessels widen by 53 per cent. This was due to improved functioning of the endothelium, the inner wall cell lining of blood vessels, scientists believe.
The tomato pill had no effect on healthy volunteers whose blood vessels were already "normal".
Constriction of blood vessels reduces blood flow and is one of the main factors that can lead to heart attacks and strokes.
The study involved randomised trials to measure the function of blood vessels, called forearm blood flow, which is predictive of future cardiovascular risk. Thirty-six cardiovascular disease patients and thirty-six healthy volunteers were given either an off-the-shelf supplement containing 7mg of lycopene called Ateronon or a placebo.
The patients with cardiovascular disease were all on cholesterol-lowering statins. However, despite this, they still had a relatively impaired function of the endothelium - the inner lining of blood vessels - compared with healthy volunteers.
This function is determined by the response of blood vessels in the forearm to a naturally occurring molecule called acetylcholine.
Endothelial function predicts future events, so having a healthy endothelium is an important factor in preventing the evolution of heart disease.
Lead scientist Dr Joseph Cheriyan, from Addenbrooke's Hospital and Cambridge University, said: "We've shown quite clearly that lycopene improves the function of blood vessels in cardiovascular disease patients.
"A daily 'tomato pill' is not a substitute for other treatments, but may provide added benefits when taken alongside other medication. However, we cannot answer if this may reduce heart disease - this would need much larger trials to investigate outcomes more carefully."
Professor Jeremy Pearson, associate medical director at the British Heart Foundation, said: "Further work is needed to understand whether the beneficial effects seen in this small study translate into clinical benefit for at-risk patients."