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.
Kim HR, Rajaiah R, Wu QL, et al. Green tea protects rats against autoimmune arthritis by modulating disease-related immune events. The Journal of Nutrition.;138(11):2111–2116.2008