Polyphenol EGCG taken from green tea leaves inhibits cancer cell growth, researchers have found.

EGCG binds to a key enzyme–dihydrofolate reductase (DHFR)–that stops the enzyme from triggering the manufacture of new DNA in tumor cells.

It appears to work in the same way as the cancer drug methotrexate, but in practice would probably have fewer side effects. The researchers are using EGCG as the starting point to design and develop effective new anti-cancer drugs that kill tumor cells but inflict less damage on healthy cells.