A chemical found in the tea, which has been drunk for over 4,000 years, has been shown to reduce the amount of cell death which follows such trauma.

Cell death leads to tissue death and even organ failure.

Experts from the UK's Institute of Child Health carried out the study, published in the journal of the Federation of Experimental Biology.

Green tea was frequently used in the past as fluid supply for patients suffering from infectious diseases, but recently researchers have begun to scientifically determine the health benefits of green tea.

During a heart attack, the amount of oxygen and nutrients reaching the brain and heart is reduced, which leads to cell death and causes irreversible damage.

'Minimise damage'

The team of researchers, led by Dr Anastasis Stephanou, carried out laboratory tests on heart cells which found that a major chemical component of green tea known as epigallocatechin-3-gallate (EGCG) can reduce cell death after a heart attack or stroke.

It appears to block the action of a protein called Stat 1, which becomes activated within cells after a stressful event such as a heart attack or stroke, and plays a role in inducing cell death.

EGCG also appears to speed up the recovery of heart cells. This allows the tissues to recover, alleviating damage to the organs.

Molecular biologist Dr Anastasis Stephanou, who led the research, said: "We're extremely encouraged by these findings and hope to implement them in the clinical setting to minimise cell death activation levels in patients with acute coronary artery disease."

He said more research would have to be carried out before patients could be advised to drink green tea after a heart attack or stroke.

"But hopefully we will one day be able to tell patients who are susceptible to heart disease that they can drink green tea for its therapeutic benefits."

Belinda Linden, head of medical information at the British Heart Foundation said: "Green tea has, in the past, been associated with a reduced risk of coronary artery disease, with claims that its high antioxidant properties may cut the amount of cholesterol in the artery wall.

"The results suggest that there may be other ways that green tea could protect the heart, but larger controlled studies would be needed to confirm this benefit."