Rheumatoid arthritis (RA), especially active disease, is associated with considerable changes in body composition, lipids, adipokines and insulin sensitivity. Metabolic changes, such as increased total cholesterol, LDL cholesterol and triglyceride levels, occur even in preclinical RA. Active RA is associated with decreased lipid levels, BMI, fat and muscle mass, as well as altered lipid profiles. Some of these changes are also seen in metabolic syndrome, and could increase cardiovascular mortality. Importantly, the systemic inflammation underlying RA is an independent risk factor for cardiovascular disease. This Perspectives article summarizes data on the associations of various components of metabolic syndrome with RA, and discusses the effects of biologic therapy on these factors. The authors propose that components of metabolic syndrome should be monitored in patients with RA throughout the disease course, and argue that optimal disease control using biologic agents might attenuate several adverse effects of metabolic syndrome in these patients.