CRP and rheumatoid arthritis: Several limitations cannot be neglected in the above two systematic reviews; thus, despite the known anti-inflammatory properties of total omega-3 PUFAs, attributed to their ability to reduce the production of cytokines (67) and C-reactive protein (CRP) (68) in previous clinical observational studies, the available data from two recent MR studies provided less convincing evidence to support the use of omega-3 PUFAs in the prevention or treatment of rheumatoid arthritis (21) and systemic lupus erythematosus (22).