A randomized trial of the Mediterranean diet for primary prevention of cardiovascular disease showed that adherence to this diet, supplemented with extra-virgin olive oil or nuts, significantly reduced the risk of major cardiovascular events. The study, conducted in Spain, enrolled 7447 participants aged 55 to 80 years with no existing cardiovascular disease but high risk. Participants were randomly assigned to one of three diets: a Mediterranean diet with extra-virgin olive oil, a Mediterranean diet with nuts, or a control diet with advice to reduce dietary fat. Over a median follow-up of 4.8 years, 288 major cardiovascular events occurred, with 96 in the olive oil group, 83 in the nuts group, and 109 in the control group. Multivariable-adjusted hazard ratios were 0.70 and 0.72 for the olive oil and nuts groups, respectively, compared to the control group. The Mediterranean diet with either supplement was associated with a 30% relative risk reduction and a 3 per 1000 person-years absolute risk reduction. No diet-related adverse effects were reported. The study supports the benefits of the Mediterranean diet for cardiovascular risk reduction, particularly in high-risk individuals. The results are consistent with previous observational studies and suggest a causal role for the diet in preventing cardiovascular disease. The study was funded by the Spanish government and other organizations. The authors report potential conflicts of interest related to their affiliations and funding sources.A randomized trial of the Mediterranean diet for primary prevention of cardiovascular disease showed that adherence to this diet, supplemented with extra-virgin olive oil or nuts, significantly reduced the risk of major cardiovascular events. The study, conducted in Spain, enrolled 7447 participants aged 55 to 80 years with no existing cardiovascular disease but high risk. Participants were randomly assigned to one of three diets: a Mediterranean diet with extra-virgin olive oil, a Mediterranean diet with nuts, or a control diet with advice to reduce dietary fat. Over a median follow-up of 4.8 years, 288 major cardiovascular events occurred, with 96 in the olive oil group, 83 in the nuts group, and 109 in the control group. Multivariable-adjusted hazard ratios were 0.70 and 0.72 for the olive oil and nuts groups, respectively, compared to the control group. The Mediterranean diet with either supplement was associated with a 30% relative risk reduction and a 3 per 1000 person-years absolute risk reduction. No diet-related adverse effects were reported. The study supports the benefits of the Mediterranean diet for cardiovascular risk reduction, particularly in high-risk individuals. The results are consistent with previous observational studies and suggest a causal role for the diet in preventing cardiovascular disease. The study was funded by the Spanish government and other organizations. The authors report potential conflicts of interest related to their affiliations and funding sources.