As the world starts to eat more meat, two bad things happen. One, people's health suffers, because high-meat diets are associated with higher rates of cardiovascular disease, diabetes, and cancer. And two, greenhouse gas emissions go up, because ruminant animals, like cows, produce more methane (a potent climate-altering gas) than plants do.
A new study, from researchers at Oxford University, quantifies how bad things could be for the planet if the developing world follows the U.S. standard of meat consumption, and, conversely, how much better things would be if people ate their recommended dose of vegetables and fruits. By 2050, it estimates a global reduction in premature deaths of 6%-10% (or 5.1 million deaths avoided per year) and that greenhouse gas emissions could be reduced by 29%-70% compared to a business-as-usual scenario. In money terms, the benefit savings of more carrots and leeks would be staggering: $1 trillion to $31 trillion by mid-century.
The numbers are so great because agriculture is associated with a quarter of all greenhouse emissions, with 80% of that coming from livestock production. Meanwhile, coronary heart disease, stroke, type 2 diabetes and cancer accounted for 40% of all deaths in 2010, the reference year for the study.
Led by Marco Springmann, from the Oxford Martin Program on the Future of Food, the research also models the impact by region and development status. The largest environmental and health benefits are in developing countries. Low-income countries in the Western Pacific alone could see a reduction of 264,000 deaths just from the climate change side. East Asia (31%–35%) and South Asia (15%–19%) account for the greatest percentage of deaths avoided for health reasons.
"The size of the projected benefits ... should encourage researchers and policy makers to act to improve consumption patterns," the researchers say. But they're not under any illusion about the size of the task. Just meeting standard dietary guidelines would mean a 25% increase in vegetable and fruit consumption, and an enormous 56% reduction in red-meat intake. At the same time, people would also need to eat less calories. The possible dividends of less meat are enormous, but so are the changes required.