Thirty-three male subjects were randomly allocated to one of three treatments which involved the consumption of 50 g/d of either one of three spreadable fats for twelve weeks. Group A consumed their normal spreadable fat; group B consumed a low-fat spread (40% fat wt/wt) which contained 8 g of fish oil per 100 g of product; group C consumed a high-fat spread (80% fat wt/wt) which contained 8 g of fish oil per 100 of product. Baseline levels of platelet phospholipid eicosapentaenoic acid (C20:5 n-3) were < 1.0% wt/wt at baseline in all groups and increased significantly (p < 0.05) in both groups receiving fish-oil containing spreads (12 week values of 1.5 +/- 0.5 for group B and 2.4 +/- 1.3 for group C). There was no change in the control group receiving their normal spreads. The ratio of all n-6; n-3 polyunsaturated fatty acids fell significantly in group B (12.5 +/- 3.1 v 1.7 +/- 1.9) and in group C (8.2 +/- 3.9 v 6.7 +/- 2.6), both of whom received fish oil. These two groups also achieved a significant (p < 0.05) increase in platelet phospholipid docosahexaenoic acid (C22: 6 n-3): 2.3 +/- 0.5 v 2.9 +/- 0.9 in group B and 2.3 +/- 0.6 v 3.1 +/- 0.9 in group C. The subjects encountered no important palatability or acceptability difficulties. These data show that, in individuals with low intakes of fatty fish, spreadable fats enriched with fish oil are a useful vehicle for ensuring adequate intakes of n-3 polyunsaturated fatty acids.