Aligning national food systems with global goals is required for sustainable transitions. We examine if realistic, context-specific dietary changes, mindful of Swedish food culture and in line with future scenarios, are sufficient to meet ambitious environmental goals. Here, we quantified diets based on the four Swedish Food Futures scenarios, which reflect prospects of technological development, behavioral change, import trends, and values. Scenario diet nutritional intakes and environmental impacts were quantified and related to health targets and nationally adapted climate, cropland, and biodiversity boundaries. Dietary changes in scenario diets reduced environmental impacts by 30% compared to current diets. No scenario stayed within the strictest climate boundary without removal of energy-related food chain emissions—resulting in 50–60% additional impact reduction. Food chain waste reduction by 50% resulted in an additional 8–10% reduction in impacts. Dietary changes can make substantial contributions to staying within global climate, cropland, and biodiversity boundaries and meet health targets, but improvements in production and waste reductions are also required.