Leaving the mean: Exploring carbon emission distributions as a route to a sustainable diet

The supply of goods such as food or buildings accounts for a considerable fraction of world greenhouse gas emissions. Analyses are often led by a discussion of individual materials or the mean emissions from selected categories – for example vegetarian diets or concrete framed buildings. In this work, we introduce the idea of exploring the form and shape of distributions as a way to develop emission reduction policy. Dietary data from 3558 individuals is combined with emission intensity values for 94 food categories and the results examined through an extensive statistical analysis. Whilst the range of emissions from vegetarians is narrow (5.54 kgCO2e/day) for meat eaters it is significantly greater (21.65 kgCO2e/day). This suggests that meat eaters can reduce their emissions considerably by simply moving within this distribution, rather than by giving up meat. It is found that if only the 25 % of meat eaters with the …