Is a diet low in greenhouse gas emissions a nutritious diet? – Analyses of self-selected diets in the LifeGene study

BACKGROUND: Climate change is an urgent global issue and the food sector is a major contributor to greenhouse gas emissions (GHGE). Here we study if a diet low in GHGE could be a nutritious diet compared to the Nordic Nutrition Recommendations (NNR). METHODS: The environmental impact of foods from Life Cycle Assessment (LCA) data was linked to a food frequency questionnaire (FFQ) filled out by 5,364 participants in the Swedish LifeGene study. Thereafter, we calculated the daily emission of CO(2) equivalents (CO(2)e) as well as the intake of selected nutrients associated with vegetables, fruits, meat and dairy products. The CO(2)e was divided into quartiles were quartile 1 corresponds to a diet generating the lowest CO(2)e, and quartile 4 corresponds to a diet with the highest CO(2)e. RESULTS: The overall diet-related emission was 4.7 kg CO(2)e/day and person, corresponding to 1.7 ton CO(2)e/year. In general, there were only small differences in nutrient intake between groups of varying levels of CO(2)e, regardless if the intake was analyzed as absolute intake, energy percent or as nutrient density. Moreover, adherence to NNR was high for the group with the lowest CO(2)e, except for saturated fat where the intake was higher than recommended for all CO(2)e groups. On the other hand, only the group with the lowest CO(2)e fulfilled recommended intake of fiber. However, none of the CO(2)e groups reached the recommended intake of folate and vitamin D. CONCLUSIONS: Here we show that a self-selected diet low in CO(2)e provides comparable intake of nutrients as a diet high in in CO(2)e. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13690-017-0185-9) contains supplementary material, which is available to authorized users.