A study just published in the Proceedings of the National Academy of Sciences (PNAS) reaffirms that reducing meat consumption can improve your health and lower your carbon footprint. It starts with the premise that the food system accounts for more than 25% of GHG emissions (80% associated with livestock production) and that poor eating habits contribute to more than a billion people worldwide whose obesity put them at risk of premature death. Hypothesizing that “simply” changing diets might have more impact than other mitigation options, the study looked at four ways of eating (from status quo to vegan), and assessed the impacts of implementing them regionally, in terms of GHG emissions, health effects, and costs.
- On health: Compared with the reference scenario, following global dietary guidelines (HGD) would result in 5.1 million avoided deaths per year and 79 million years of life saved. For the vegetarian diet, 7.3 million avoided deaths and 114 million life years saved, and for the vegan diet, 8.1 million avoided deaths and 129 million life years saved.
- On GHG emissions: Compared with the projected GHG emissions from food consumption in 2050 (which are expected to increase 51% over 2005/07 reference level), following HGD would result in a 29% reduction (or 7% increase from 2005/2007 reference). For the vegetarian and vegan diets, GHG emissions reductions were 63–70% below the 2050 level (45–55% lower than the 2005/2007 level).
For more on the costs savings, both in terms of health and environment, as well as more details on the methodology, read here.