We analyse ex-ante the effects of diet recommendations in France, Finland and Denmark. The simulation approach combines a behavioural model of adjustment to dietary constraints, an epidemiological model and an LCA model. We conclude that for the three countries: 1- The promotion of several diet recommendations would improve social welfare; 2- Healthy-eating recommendations targeting consumption of saturated fat, fruits/vegetables and salt should be prioritized for promotion; 3- Although synergies dominate, trade-offs between environmental and health objectives may occur in Finland and Denmark; and 4- The taste/utility cost of dietary change imposed on consumers should be included in the welfare analysis of diet recommendations.