So say scientists from the University of Michigan Medical School. They included Salah-uddin Ahmed, PhD.
The scientists studied joint cells called synovial fibroblasts that had been affected by rheumatoid arthritis.
First, the researchers treated some RA synovial fibroblasts with EGCG. For comparison, they didn't treat other synovial fibroblasts with EGCG.
Next, the scientists exposed both sets of synovial fibroblasts for 24 hours to an inflammatory chemical linked to RA.
The EGCG-treated cells produced lower levels of two other inflammatory chemicals than cells that hadn't been treated with EGCG. In fact, the highest tested dose of EGCG virtually halted production of those inflammatory chemicals during the experiment.
Further lab tests show that EGCG blocked a chemical chain reaction linked to inflammation and joint damage.
"The results from this study suggest that EGCG may be of potential therapeutic value in regulating the joint destruction in RA," write Ahmed and colleagues.
The study doesn't show whether drinking green tea has the same effect or how much green tea would be needed to achieve the results.
The findings were presented in Washington, D.C., yesterday at Experimental Biology 2007, an annual scientific meeting that includes several scientific societies.