The primary objective of this study was to determine whether it is the fish oil itself or the alpha-tocopherol that is added to the fish oil preparations (to prevent peroxidation) that is responsible for the beneficial effects of dietary supplementation with fish oil in patients with rheumatoid arthritis (RA). One group of RA patients took fish oil supplements and another group took alpha-tocopherol-enriched coconut oil supplements (placebo controls), both for 3 months. Clinical and laboratory indices of RA activity in relation to cellular and plasma vitamin E levels were assessed at the beginning and the end of the trial. The results of the study provide evidence that the beneficial effects of fish oil supplementation cannot be ascribed to the antioxidizing properties of the alpha-tocopherol per se.