OBJECTIVES:Studies have shown that cranberry (Vaccinium macrocarpon) has antiinflammatory and antioxidant effects; however, to our knowledge, the effects of cranberry juice consumption have not been studied in patients with rheumatoid arthritis (RA). The aim of this study was to verify the effect of cranberry juice consumption on several inflammatory biomarkers and on the disease activity of patients with RA.METHODS:A prospective study was conducted with 41 women diagnosed with RA. The disease activity measured by Disease Activity Score 28 (DAS28) and anticyclic citrullinated peptide (anti-CCP) antibodies, and several inflammatory and biochemical biomarkers were analyzed. The control group (n = 18) maintained their usual diet. The cranberry group (n = 23) consumed 500 mL/d of low-calorie cranberry juice.RESULTS:Regarding the baseline values, the cranberry group presented a decrease in the values of DAS28 (P = 0.048) and anti-CCP (P = 0.034) after 90 d of treatment, whereas changes in inflammatory biomarkers were not found.CONCLUSION:The present study indicated that cranberry juice decreases disease activity and therefore has beneficial effects for RA patients, although larger and long-term studies are needed to definitively probe this effect and to clarify the mechanisms involved.