OBJECTIVES:Rheumatoid arthritis (RA) is one of the most prevalent chronic autoimmune diseases;it typically involves the hands,wrists,ankles,and eventually all joints.Some studies have reported that zinc serum levels are lower in patients with RA than in healthy individuals.MATERIALS and METHODS:Seventy-nine patients with RAwere selected.The patients were all less than 75 years old and were diagnosed by a rheumatologist.Serum zinc levels were measured using the flame photometry method with a blood sample of 5 mL.The relationship between the average serum zinc level and disease activity was analyzed based on the DAS28 scoring scale for different RA groups.The significance threshold was set at p ＜ 0.05.Data analyses were implemented in SPSS 22.0.RESULTS:There was a significant inverse relationship between the serum zinc levels and disease activity.Chi-square tests were used to compare zinc serum levels with respect to disease activity.There were significant differences in zinc levels among three groups of patients with different levels of disease severity,such that disease activity increased as the serum zinc level decreased (p ＜ 0.001).CONCLUSION:There was a significant inverse relationship between the serum zinc level and RA activity based on the DAS28 score.Therefore,it is recommended that mineral deficiencies should be addressed by optimizing the zinc supply along with other standard medications in order to reduce RA activity.