Background: Recent statistics indicate that acute myocardial infarction (AMI) is becoming very common in the State of Bahrain. A population-based case-control study was carried out to explore the importance of lifestyle in the occurrence of AMI in Bahrain among those aged 30-79 years. Methods: Seventy consecutive cases with a first episode of AM) were identified from a register, which included all hospital admissions, during the period 1 February 1992 to 31 July 1992, and compared with 516 subjects obtained from a random sample of the same community. Multiple logistic regression was used to control for demographic variables as well as for the mutual confounding effects of the investigated risk factors. Results: Of the patients with first-time AMI, 64% did not walk regularly for exercise compared with 34% of community controls (adjusted odds ratio (OR) = 3.06, 95% confidence interval (CI): 1.24-5.15). In all, 12% of community controls has a history of hypertension and 9% had diabetes. The comparative figures for AMI patients were 44% for hypertension (adjusted OR = 5.04, 95% CI: 2.82-9.00) and 22% for diabetes (adjusted OR = 3.28, CI: 1.73-6.20). Cigarette smoking and infrequent consumption of fruits and vegetables also appeared to be associated with an increased risk of AMI. Conclusion: There is scope for lifestyle change in reducing AMI risk, by changes in physical activity, smoking and dietary habits. In addition, measures to control hypertension and diabetes should be given a high priority in any national health policy to prevent AMI.