The objective of this study was to determine whether cod liver oil supplementation helps reduce daily NSAID requirement of patients with rheumatoid arthritis (RA). A dual-centre, double-blind, placebo-controlled RCT study of 9 months’ duration was conducted. Ninety-seven patients with RA were randomised to take either 10 g of cod liver oil containing 2.2 g of n-3 EFAs or air-filled identical placebo capsules. Documentation of NSAID daily requirement, clinical and laboratory parameters of RA disease activity and safety checks were done at 0, 4, 12, 24 and 36 weeks. At 12 weeks, patients were instructed to gradually reduce, and if possible, stop their NSAID intake. Relative reduction of daily NSAID requirement by >30% after 9 months was the primary outcome measure. Fifty-eight patients (60%) completed the study. Out of 49 patients, 19 (39%) in the cod liver oil group and out of 48 patients, 5 (10%) in the placebo group were able to reduce their daily NSAID requirement by >30%. No differences between the groups were observed in the clinical parameters of RA disease activity or in the side-effects observed.