Adopting certain diets could help both humans and the planet avoid chronic health ailments.
Shifting to diets that buck global trends of increased meat consumption could cut projected greenhouse gas emissions and conserve natural habitats, according to a University of Minnesota study published last week.
The research found that an international adoption of regimens low in meat and high in grain and produce would reduce the amount of land clearage necessary to meet global food demands.
Converting to Mediterranean, pescetarian or vegetarian diets would also diminish projected agricultural
production emissions per capita by 30 percent, 45 percent and 55 percent, respectively, the study found.
“We showed that the same dietary changes that can add about a decade to our lives can also prevent massive environmental damage,” said ecology, evolution and behavior regents professor David Tilman in a University press release.
According to the research, rising global incomes have grown the demand for diets high in refined sugars, fats, oils and meats.
“Generally, as people get more affluent, they eat more calories, more meat and more empty calories,” said Mike Clark, a natural resources science management doctoral student who worked with Tilman and co-authored the two-year study.
Producing more food requires clearing more land, which contributes to rising greenhouse gas emissions, Clark said. Current dietary trends are expediting those environmental impacts, he said.
If unchecked, the current global dietary trends could contribute to an 80 percent jump of greenhouse gas emissions by 2050 stemming from agriculture, the study said, while also driving an increase in illnesses like type 2 diabetes and coronary heart disease.
The research traced worldwide trends using dietary consumption and agricultural yield data from the Food and Agricultural Organization of the United Nations. It also aggregated the results of other scientific studies focused on the health outcomes and gas emissions of different diets and foods, Clark said.
Switching to the nutritional regimens suggested by the research’s findings would have a major impact across the globe.
“This dietary shift would prevent the destruction of an area of tropical forests and savannas as large as half of the United States,” Tilman said in the press release.
The ‘extremely difficult’ road to protecting land, human health
Increased consumption of meat has driven agricultural production away from more efficient plant-based systems, said Don Wyse, agronomy professor and co-director of the Center for Integrated Natural Resources and Agricultural Management.
“Most of the production of grain crop products in the Midwest does not feed people directly,” Wyse said. “Most all of that goes through livestock to produce meat.”
We put more protein into cattle than we get back from them, as they require more space and consume large amounts of feedstock, Clark said.
“You have 20 units of plants going in to feed one unit of beef,” he said, “whereas you could instead be eating those 20 units of plants.”
As wealth in developing countries increases, so does the demand for luxury items — which include meat, he said.
Clark said when he visited communities in the Ecuadorian stretch of the Andes Mountains in South America, he saw firsthand how communities tend to model the lifestyles of wealthy nations as they develop economically.
“People there would have TVs and cars even if they didn’t necessarily need them,” Clark said. “This is what other people who are more affluent have, and so they want to strive towards that.”
He said it could take a mix of public awareness, education and, potentially, new policies to transition consumption patterns toward more sustainable diets.
“It’s going to be extremely difficult,” Wyse said. “Diets are a part of culture.”
Researching new agricultural systems that can produce plants to feed livestock while also maintaining healthy landscapes could also address environmental concerns raised in the study, he said. University researchers have been developing ecologically friendly farming methods since the start of the millennium, he said.
“What I think the grand challenge is, is to figure out how to do both — how to produce agricultural systems that … provide for landscape health and for human health,” Wyse said.