Vegans love to extol the benefits of their diet, and from environmental impact to animal welfare, there are many. But when it comes to helping feed our expanding global population using the land we've got here in the US, a vegan diet isn't the best option, according to a new study from US researchers.
In fact, continuing to eat some meat would allow American farmlands to feed more people overall, than if everyone switched over to veganism.
Figuring out how to feed an exploding global population without converting ever more swaths of land to agriculture is an ongoing challenge. The UN's Food and Agriculture Organization estimates we need to increase food production globally by 60 percent over the next 35 years to meet demand. How America uses its farmland affects not only how secure food is in the US, but it could also impact the availability of food worldwide.
In this context, researchers compared 10 different diets, based on how efficiently they use America's farmland. The "baseline" diet was modeled off what the average American eats, according to the Department of Agriculture. They compared this to other diets, in which various percentages were either "healthy omnivorous"—calories came from all sources, including meat, plants, eggs and dairy—or vegetarian, which included milk and eggs, but no meat. Three strictly vegetarian diets were also included in the study (egg and dairy, just dairy, and vegan).
The results, published Friday in the journal Elementa, showed that while reducing meat consumption can increase the number of people fed by America's farms, there's a limit to that advantage. A completely vegan food system would actually feed fewer people than vegetarian or some omnivore diets.
According to this study, the number of people who could be fed by US farmland increased as meat consumption was reduced, but only up to a certain limit. While American farmlands could feed 402 million people eating the average diet, it could feed more than double—807 million—on a dairy-only vegetarian diet. However, when it came to vegan diets, our available farmland could feed 735 million people.
What's key here is that not all farmland is suitable for every purpose. Some grazing areas used to raise livestock like cows simply wouldn't be viable for growing crops, which means that it would be wasted in a vegan-only world. Likewise, our current average diet devotes about 80 percent of our croplands—acreage could be used to grow food for people—to producing feed crops for livestock instead.
Researchers found the most efficient use of our land was supporting a dairy-inclusive vegetarian diet, because it maximized how much land was used to produce food, and could feed the highest number of people.
"Our approach challenges the 20th century emphasis on increasing yield and production," lead author Christian Peters, an associate professor at Tufts University Friedman School of Nutrition Science and Policy, said in a press release. "Improving crop yields remains vitally important, but it is not the only way to increase the number of people fed per acre. Our aim is to identify potential agricultural-sustainability strategies by addressing both food consumption and production."
But convincing the entire US population to switch to a vegetarian diet, even one that includes cheese and ice cream, is an unrealistic goal—only 2 percent of Americans are vegan or vegetarian, and that number has stayed stable for decades. Luckily, that's not the only takeaway from this research: it also showed that simply reducing how much meat we eat could have a major impact. The study found that eating a mostly omnivore diet and just being vegetarian 20 percent of the time increased the number of people who could be fed by 36 percent.
There won't be a magic bullet solution to food insecurity, but practical steps—like switching to Meatless Mondays—will help us get closer to a solution.