System-level intervention at daycare shifts children toward plant-based, climate-friendly eating

The intervention was co-designed through workshops with food service staff, daycare professionals, and municipal leaders to ensure practical feasibility. Children's dietary intake was measured using food frequency questionnaires at baseline, mid-term, and end of intervention. The results were striking: legume and legume-product consumption increased significantly, local fish consumption rose, and red meat, sausages, and other processed meat products fell sharply (Bonferroni-corrected p < 0.001). Effect sizes were substantial, ranging from 0.9 to 2.69. Importantly, total nutrient intake remained stable—the dietary shift did not compromise nutritional adequacy. Using standard environmental coefficients for foods, the researchers also found that the intervention reduced both the climate impact and biodiversity impact of the overall diet provided at daycare (climate: p < 0.001; biodiversity: p = 0.003). This result suggests that systemic food changes in institutional settings can reshape young children's eating patterns toward more sustainable choices without nutritional trade-off.

The large effect sizes (0.9–2.69) indicate that the dietary shifts were not marginal but clinically meaningful—children ate substantially more legumes and local fish, and markedly less red and processed meat. Notably, this happened without deliberate calorie restriction or nutrient tracking, suggesting that when the default food environment changes, children's choices follow naturally. The study also measured biodiversity impact specifically, which extends beyond simple climate metrics: plant-based protein sources and locally sourced fish typically support less land use and habitat disruption than beef or industrial meat production. One limitation is that the study measured intake at daycare only and did not track home diet, so we cannot know whether the intervention's effects persisted when children ate outside daycare or whether families compensated by offering more meat at home. The nutrient stability is important: while the menu shifted, protein, micronutrient, and energy intake all remained adequate, eliminating a common concern that plant-forward shifts might underfeed young children.