To do so, they used Exiobase, an input-output database that represents the world’s economy. The platform allows users to track the environmental costs of growing a variety of foods and the machinery needed to produce and distribute it to supermarkets. The site is also able to adjusts its figures based on a different countries’ production efficiency.
Scientists gathered information on the average diets of citizens living in 39 countries as well as its nationally recommended diets. They then entered the data into Exiobase to examine how it would affect greenhouse gas emissions, land use and eutrofication, which is the addition of nutrients to water sources that can lead to toxicities and lack of oxygen in water.
After analyzing the results, they found that if people in 28 high-income nations, including the United States, Germany and Japan, followed the dietary recommendations set by its respective governments, greenhouse gases related to the production of the food would drop by 13 to 25 percent.
Additionally, the amount of land needed to grow the food would decrease by 17 percent.
“The study shows that choosing to follow an NRD over the average national diet would have the biggest environmental savings in the United States, Australia, Brazil and Canada. Most of these savings are due to the reduction of meat in the diet. There are reductions also in most EU nations, with Greece, Ireland, and the Netherlands saving the most,” the authors wrote in a statement.
As for lower-income nations, researchers discovered following a NRD over the average national diet would result in higher environmental impacts, because these areas rely on higher consumption of animal product to combat low levels of protein.
But they say the overall benefits would still be positive.
“Although I think we could do even better, the message is a positive one, overall, especially if middle- and high-income countries modify their diets to align with nationally recommended diets,” they wrote. “This will generally mean eating more plant products such as legumes and vegetables, and fewer animal products. If you know your diet isn't healthy, you have one more reason to change, for our environment too. It might just be possible to have your cake and eat it!”