Going veggie would cut global food emissions by two thirds and save millions of lives – new study
Marco Springmann, Researcher, University of Oxfor,
March 22, 2016
THS29092017
Eating more fruit and vegetables and cutting back on red and
processed meat will make you healthier. That’s obvious enough. But as
chickens and cows themselves eat food and burn off their own energy,
meat is a also major driver of climate change. Going veggie can
drastically reduce your carbon footprint. This is all at a personal level. What about when you multiply such
changes by 7 billion people, and factor in a growing population? In our latest research, colleagues and I estimate that changes towards more plant-based diets in line with the WHO’s global dietary guidelines could avert 5m-8m deaths per year by 2050. This represents a 6-10% reduction in global mortality. Food-related greenhouse gas emissions would also be cut by more than
two thirds. In all, these dietary changes would have a value to society
of more than US$1 trillion – even as much as US$30 trillion. That’s up
to a tenth of the likely global GDP in 2050. Our results are published
in the journal PNAS. Future projections of diets paint a grim picture. Fruit and vegetable
consumption is expected to increase, but so is red meat consumption and
the amount of calories eaten in general. Of the 105 world regions
included in our study, fewer than a third are on course to meet dietary
recommendations. A bigger population, eating a worse diet, means that by 2050
food-related GHG emissions will take up half of the “emissions budget”
the world has for limiting global warming to less than 2℃. To see how dietary changes could avert such a doom and gloom
scenario, we constructed four alternative diets and analysed their
health and environmental impacts: one reference scenario based on
projections of diets in 2050; a scenario based on global dietary
guidelines which includes minimum amounts of fruits and vegetables, and
limits to the amount of red meat, sugar, and total calories; and two
vegetarian scenarios, one including eggs and dairy (lacto-ovo
vegetarian), and the other completely plant-based (vegan).
Millions of avoidable deaths
We found that adoption of global dietary guidelines could result in
5.1m avoided deaths per year in 2050. Vegetarian and vegan diets could
result in 7.3m and 8.1m avoided deaths respectively. About half of this
is thanks to eating less red meat. The other half comes thanks to eating
more fruit and veg, along with a reduction in total energy intake (and
the associated decreases in obesity). There are huge regional variations.
About two thirds of the health benefits of dietary change are projected
to occur in developing countries, in particular in East Asia and South
Asia. But high-income countries closely follow, and the per-person
benefits in developed countries could actually be twice as large as
those in developing countries, as their relatively more imbalanced diets
leave greater room for improvement.
Room for improvement.Lightspring / shutterstock
China would see the largest health benefits, with around 1.4m to 1.7m
averted deaths per year. Cutting red meat and reducing general
overconsumption would be the most important factor there and in other
big beneficiaries such as the EU and the US. In India, however, up to a
million deaths per year would be avoided largely thanks to eating more
fruit and vegetables. Russia and other Eastern European countries would see huge benefits
per-person, in particular due to less red meat consumption. People in
small island nations such as Mauritius and Trinidad and Tobago would
benefit due to reduced obesity.
Vegans vs climate change?
We estimated that adopting global dietary guidelines would cut
food-related emissions by 29%. But even this still wouldn’t be enough to
reduce food-related greenhouse gas emissions in line with the overall
cutbacks necessary to keep global temperature increases below 2°C.
India could cut its emissions and save lives – at the same time.Christopher Fynn, CC BY
To seriously fight climate change, more plant-based diets will be
needed. Our analysis shows if the world went vegetarian that cut in
food-related emissions would rise to 63%. And if everyone turned vegan? A
huge 70%.
What’s it worth?
Dietary changes would have huge economic benefits, leading to savings
of US$700-1,000 billion per year globally in healthcare, unpaid
informal care and lost working days. The value that society places on
the reduced risk of dying could even be as high as 9-13% of global GDP,
or US$20-$30 trillion. Avoided climate change damages from reduced
food-related greenhouse gas emissions could be as much as US$570
billion. Putting a dollar value on good health and the environment is a
sensitive issue. However, our results indicate that dietary changes
could have large benefits to society, and the value of those benefits
makes a strong case for healthier and more environmentally sustainable
diets. The scale of the task is clearly enormous. Fruit and vegetable
production and consumption would need to more than double in Sub-Saharan
Africa and South Asia just to meet global dietary recommendations,
whereas red meat consumption would need to be halved globally, and cut
by two thirds in richer countries. We’d also need to tackle the key
problem of overconsumption. It’s a lot to chew on.
