Objective: To assess the long-term effect of dietary advice on diet and mortality after a randomised trial of men with a recent history of myocardial infarction. Design: Questionnaire survey and mortality follow-up after a trial of dietary advice. Setting: Twenty-one hospitals in south Wales and south-west England. Subjects: Former participants in the Diet and Reinfarction Trial. Main outcome measures: Current fish intake and cereal fibre intake. All-cause mortality, stroke mortality and coronary mortality. Results: By February 2000, after 21 147 person years of follow-up, 1083 (53%) of the men had died. Completed questionnaires were obtained from 879 (85%) of the 1030 men alive at the beginning of 1999. Relative increases in fish and fibre intake were still present at 10 y but were much smaller. The early reduction in all-cause mortality observed in those given fish advice (unadjusted hazard 0.70 (95% CI 0.54, 0.92)) was followed by an increased risk over the next 3 y (unadjusted hazard 1.31 (95% CI 1.01, 1.70). Fat and fibre advice had no clear effect on coronary or all-cause mortality. The risk of stroke death was increased in the fat advice group -the overall unadjusted hazard was 2.03 (95% CI 1.14, 3.63). Conclusions: In this follow-up of a trial of intensive dietary advice following myocardial infarction we did not observe any substantial long-term survival benefit. Further trials of fish and fibre advice are feasible and necessary to clarify the role of these foods in coronary disease.