You probably recall recent blog postings and articles in my eHealthy News You Can Use newsletter about the benefits of green tea to fight bladder cancer and protect transplanted livers -- especially fatty ones -- from damage due to restrictions in blood flow.

European researchers have discovered how the flavonoid EGCG (epigallocatechin gallate), naturally present in green tea, prevents cancer cells from growing: By binding to a specific enzyme. Scientists decided to study ECGC after realizing its structure was similar to the cancer drug methotrexate. They later found EGCG can kill cancer cells the same way methotrexate does.

How does it work? EGCG binds strongly to dihydrofolate reductase (DHFR), an essential enzyme in healthy and cancerous cells, but not tightly as methotrexate, so its side effects on healthy cells may be less severe than those of the anti-cancer drug.

One very important caveat: Researchers theorize this binding of EGCG and DHFR may also explain why women who drinks large quantities of green tea during conception and early pregnancy may have an increased risk of having a child with spina bifida or other neural tube disorders. Green tea may suppress the effectiveness of folic acid.

Yahoo News March 15, 2005