Weighing The Health And Climate Benefits Of Eating Less Meat
Many of our individual choices, including what we choose to eat, can affect our health and the environment around us. Studies show that when we consume lots of red and processed meat and fewer fruits and vegetables, we are more at risk of diseases that can cause early mortality. In addition to impacts on our health, farming meat generates more greenhouse gas (GHG) emissions than farming vegetables — currently, our food system produces over 25% of global GHGs, with livestock production being responsible for up to 80% of those emissions. Reducing the consumption of meat and increasing the amounts of fruits and vegetables that we eat could mitigate the effects our current diets have on our health and the environment. A study out of the University of Minnesota has set out to examine the long-term effects of such changes.
In the study, researchers used a modelling framework to analyze the health, environmental, and economic impacts of changes in diet by examining four dietary scenarios in the year 2050. The first scenario (REF) was based on dietary and consumption projections made by the Food and Agriculture Organization of the United Nations. A second scenario (HGD) was based on global healthy eating guidelines and the assumption that people only consume enough calories to maintain a healthy body weight. The final scenarios were based on vegetarian diets—those that include eggs and dairy (VGT) and those that are completely plant-based (VGN).
The model found that, overall, reducing meat consumption and increasing the amount of fruits and vegetables in our diets had a positive effect on personal health and also reduced the levels of GHG emissions related to food production. Positive health effects included fewer deaths per year (5.1 million fewer deaths with the HGD diet, 7.3 million with VGT and 8.1 million VGN), particularly as a result of reduced coronary heart disease, stroke, diabetes and cancer. Emissions numbers also decreased from the 2005-07 measured levels. With the REF scenario, GHGs are predicted to increase by 51%, however, if the HGD diet was adopted, GHGs would be 29% less in 2050 than those that result from the REF diet and only 7% greater than the 2005-07 levels. The reductions of GHGs with the VGT and VGN diets was even more pronounced, resulting in emissions that would be 45-55% lower than the 2005-7 levels, and 63-70% lower than what they would be with the REF scenario.
An additional analysis examined the economic impacts of each of these diet scenarios looking at the “cost of illness savings” (direct and indirect health care costs, and associated costs of lost work days), and the “value of statistical life” (estimating the cost of the lives and life-years saved under each scenario). In both analyses, moving from the REF to the other diets saved money. With the cost of illness savings, moving from the REF to HGD scenario would save $735 billion in direct and informal health care costs and lost labour costs. The vegetarian and vegan diets would save $973 billion and $1,067 billion respectively. The value of statistical life analysis resulted in even higher savings. In the VGN diet scenario, it was estimated that the value associated with diet-related changes was 30 trillion US dollars per year in 2050, with the VGT diet ($28 trillion) and HGD ($21 trillion) diets also estimating savings.
The results of this analysis align with previous studies demonstrating that a reduction in meat consumption can have positive health, environmental and economic benefits. In order to achieve the results illustrated by the model, significant changes in the global food system would be necessary. This study shows the magnitude of the potential benefits, and helps identify the interventions on which researchers and policy makers can act to achieve these benefits (and which animal and environmental advocates can work together to push forward).
http://www.pnas.org/content/113/15/4146.abstract