Environmental impact of Norwegian self-selected diets: comparing current intake with national dietary guidelines and EAT-Lancet targets.

OBJECTIVES: Dietary environmental impact in a Norwegian adult population was estimated for six environmental impact categories. Moreover, environmental benefits of scenario diets complying with the Norwegian Food-Based Dietary Guidelines (FBDG) and the EAT-Lancet reference diet were assessed.

DESIGN: The current diet of Norwegian adults was estimated according to 24-hour dietary recall data from a national dietary surveillance survey (Norkost 3). Scenario diets were modelled to represent the Norwegian FBDG and the EAT-Lancet healthy reference diet. Dietary environmental impact in terms of global warming potential, freshwater and marine eutrophication, terrestrial acidification, water use, and transformation and use of land, was estimated for the current and scenario diets using environmental impact data representative of the Norwegian market. Significant associations between impact and gender/educational attainment were assessed at P <0.05.

SETTING: Norway.

PARTICIPANTS: Adults ( n= 1,787) aged 18-70 years who participated in the Norkost 3 survey (2010-2011).

RESULTS: Environmental impact varied significantly by gender and educational attainment. The food groups contributing most to environmental impact of Norwegian diets were meat, dairy, beverages, grains, and composite dishes. Compared to the current Norwegian diet, the FBDG scenario reduced impacts from 2% (freshwater eutrophication) to 32% (water use), while the EAT-Lancet scenario reduced impacts from 7% (marine eutrophication) to 61% (land use). The EAT-Lancet scenario resulted in 3-48% larger reductions in impact than the FBDG scenario.

CONCLUSIONS: The Norwegian FBDG, while not as environmentally friendly as the EAT-Lancet reference diet, can still be an important tool in lessening environmental burden of Norwegian diets.