Allium vegetable intake and risk of acute myocardial infarction in Italy

BACKGROUND: Interest in potential benefits of allium vegetables has its origin in antiquity, but the details of these benefits are still open to discussion. Only two epidemiological studies considered the relation between dietary intake of allium vegetables and cardiovascular diseases. AIM OF THE STUDY: To provide further information we analysed the relationship between onion and garlic intake and acute myocardial infarction (AMI). METHODS: We used data from a case-control study of 760 patients with a first episode of non-fatal AMI and 682 controls admitted to the same hospitals. Information was collected by trained interviewers using a validated and reproducible food-frequency questionnaire. Multivariate odds ratios (ORs) and 95% confidence intervals (CIs) were obtained after allowance for recognized confounding factors. RESULTS: Compared with non-users, the ORs of AMI for subsequent categories of onion intake were 0.90 (95% CI: 0.69-1.21) for <1 portion of onion per week and 0.78 (95% CI: 0.56-0.99) for > or = 1 portion per week. For garlic, the ORs were 0.84 (95% CI: 0.66-1.09) for intermediate and 0.94 (95% CI: 0.68-1.32) for high use, compared with no or low use. CONCLUSION: The current study, the first from Mediterranean countries, suggests that a diet rich in onions may have a favourable effect on the risk of AMI.