A key ingredient of green tea may provide protection from arthritis.
Sheffield University scientists have found that an anti-oxidising enzyme - epigallocatechin gallate, or EGCG - seems to halt the breakdown of cartilage.
David Buttle, reader in genomic medicine, and Clair Adcocks, a postdoc, believe the discovery may lead to pharmaceuticals tackling rheumatoid and osteoarthritis.
"We have found something that prevents joints from being destroyed, at least in vitro," Dr Buttle said.
Green tea's health-promoting properties have long been recognised. Its consumption has been linked to the prevention of cancer, currently the subject of a clinical trial in the United States.
The brew is a mixture of naturally occurring plant extracts. Among them is a group of bioactive chemicals called catechins, which are believed to alleviate clinical conditions such as stroke, cardiovascular disease, bacterial infections and stomach ulcers.
Dr Buttle found that green tea extract containing the catechin EGCG prevented bovine cartilage from being broken down by enzymes.
Most arthritis treatments ease the inflammation that the disease induces. Dr Buttle believes his catechin could tackle the other component - the degradation of joints through the destruction of cartilage.