More and more people are moving to vegetarian, or mostly-vegetarian, diets these days as a way to improve health and longevity. There is a strong connection between eating a plant-based diet and the reduction of health risks like type 2 diabetes, heart disease, cancer, and early mortality.
There’s another reason to eat a mostly vegetarian diet: It could help reduce the buildup of greenhouse gases that has been escalating and help keep the earth and its atmosphere much cleaner and greener.
The new research looked over past studies on various diets, their long-term health effects, costs of food production, and dietary trends over recent years to arrive at a picture of how both health and the earth would be affected if people switched from diets heavy on animal protein to mostly vegetarian diets.
The same dietary changes that can add about a decade to our lives can also prevent massive environmental damage.
“We showed that the same dietary changes that can add about a decade to our lives can also prevent massive environmental damage,” said author David Tilman in a news release.
“In particular, if the world were to adopt variations on three common diets, health would be greatly increased at the same time global greenhouse gas emissions were reduced by an amount equal to the current greenhouse gas emissions of all cars, trucks, plans trains and ships.”
The three diets Tilman mentions are a vegetarian diet, Mediterranean diet, and a pescetarian diet (in which one eats fish but no other animal protein). It may seem like more Americans are switching to these diets, but the reality is that the typical Western diet — heavy on red meat, eggs, and dairy — is becoming more widespread in other parts of the world, which may previously (and ironically) have eaten healthier diets.
The researchers predict that the current trends, by 2050, could lead to an 80% increase in greenhouse gasses due to both deforestation and gas emissions from animal farms.
So eating a plant-based diet is good not only for health, but it could also mostly or completely cancel out the huge increase in greenhouse emissions that’s projected over the coming years, they found. Parts of the U.S. may be slowly moving in that direction, but many people continue to eat diets heavy in meat and animal products.
And for countries that used to eat plant-based diets, but are increasingly favoring a diet heavier in meat, things are slightly more complicated. Rather than convincing these people to try a new kind of diet, public health messages should perhaps convince them that what they were doing in the first place is really the better way after all.
The study was carried out by a team at the University of Minnesota and published in Nature.