The National Center for Complementary and Alternative Medicine, one of the research centers of the federal government’s National Institutes of Health, has posted this summary of a recent study of green tea and rheumatoid arthritis on its website:
Rheumatoid arthritis (RA) is an autoimmune disease that affects more than 2.1 million Americans. It is characterized by joint pain, stiffness, inflammation, swelling, and sometimes joint destruction. Nonsteroidal anti-inflammatory drugs are the standard treatment for RA, but their prolonged use is associated with adverse effects and discomfort. Natural plant alternatives like green tea are being investigated for the management of RA. Green tea is the most widely consumed beverage in the world, and its polyphenols (substances rich in antioxidants) possess anti-inflammatory properties.
NCCAM-funded investigators at the University of Maryland and Rutgers University examined the effects of green tea polyphenols on RA by using an animal model in rats. The animals consumed green tea in their drinking water (controls drank water only) for 1 to 3 weeks before being injected with heat-killed Mycobacterium tuberculosis H37Ra to induce arthritis. The researchers found that green tea significantly reduced the severity of arthritis.
The researchers suggest that green tea affects arthritis by causing changes in various arthritis-related immune responses—it suppresses both cytokine IL-17 (an inflammatory substance) and antibodies to Bhsp65 (a disease-related antigen), and increases cytokine IL-10 (an anti-inflammatory substance). Therefore, they recommend that green tea be further explored as a dietary therapy for use together with conventional treatment for managing RA.
References and further information from NCCAM at:
See also the NYBC entry on Green Tea (Jarrow).
Other studies of green tea are reported on this blog; see “Green Tea” category in the sidebar.