If everyone became vegetarian, would the planet actually be better off?

Cutting back on red meat is probably the best place to start, but eating the right types of veggies is important, too.

People forego eating meat for a variety of reasons. Some do it in an attempt to eat healthier meals while others make the shift because they think cows and pigs are simply cuter than they are delicious. Some might even switch over because they think it will help the planet. But what would happen if every single human decided to become a vegetarian? Would we be harming or helping our planet? It turns out, reducing our animal product intake (especially red meat) might not be such a terrible place to start.

How exactly does meat consumption affect the environment?
Red meat production, which includes all of the steps that go into supplying the animals that turn into hamburgers, takes a toll on the environment in the form of greenhouse gases and the land we use.

“Red meat production has major impacts on almost every aspect of [the] environment,” says Walter Willett, a Professor of Epidemiology and Nutrition at Harvard. “The greenhouse gas production is probably one of the most serious and acute because it’s apparent that our planet is warming faster than anybody anticipated even just a few years ago.”

Willett says this comes from two steps in the cattle production process. The first is that we lose a lot of energy in the process between growing the grains that we feed the cattle and using the animals for food. That's because many farm animals, especially cattle, are inefficient converters, meaning that they consume more food than they are able to provide. The second problem is the amount of methane that cows create. On average, cows produce around 100 to 500 liters of methane per day in the form of flatulence. That methane is about 30 times more potent as a heat-trapping, or greenhouse gas.

“The biggest piece of grain use is about 45 percent, which is fed to animals, largely cattle," says Willett. "We produce a huge amount of carbon dioxide and methane in that process. Then we eat the red meat, and the red meat itself is very damaging to human health in the amount that we consume it. That is both damaging planetary and human health at the same time."

So, to sum up, cow farts plus the massive amount of grain production needed to feed them is pretty disastrous for both land use and greenhouse gas production.

“Certainly the way that we produce meat currently and in the quantities that we produce meat, it’s much more impactful on the environment from a variety of indicators including carbon footprint, land use, and water use,” says Martin Heller of the Center for Sustainable Systems at the University of Michigan.

What if we all became vegetarians?
If meat, especially red meat, is so bad, what if we just stopped eating it all together? Would that solve all of these problems?

Switching from an omnivorous to vegetarian diet could reduce a person's carbon footprint by about 30 percent, says Martin Heller, an engineer at the Center for Sustainable Systems at the University of Michigan. However, he says, some meat might not be a terrible thing if you’re struggling with the idea of giving it up.

“The caveats to why a vegetarian diet may not be the lowest. There are opportunities [for] using ruminant animals to eat grass on land that isn’t suitable for cultivation of other crops,” he says. “There’s kinds of small niche types of productions systems that are rather atypical in our current agricultural production that could offer situations where significant high quality calories could be produced at a lower impact than growing a field of beans.”

In other words, if there’s grazing land that couldn’t sustainably grow anything, that land could be used for cattle. That way, cattle could be raised in a way that doesn’t destroy our environment. And if we only raised cattle on this type of land, that would end up reducing our worldwide consumption of red meat dramatically, says Willett.

There’s also the concern for human health. Just because a plant based diet is in fact plant based, that does not mean it’s necessarily healthy.

“You do need to be careful there, because not all plant foods are health foods,” Willett says. “Coca Cola and Dunkin Donuts are plant-based foods and are obviously bad for human health. But, a plant-based diet should really focus more on fruits, vegetables and whole grains, and for protein sources, legumes and seeds would be much better for human health than the average American diet.”

So, if I’m a vegetarian, am I at least environmentally off the hook?
Giving up meat, especially red meat, isn’t a bad start to making your dietary carbon footprint shrink a bit. However, even if you’ve done that, there’s other ways to make sure that you are making the most sustainable choices.

“For example, a vegetarian may be eating a diet with major environmental impacts because they are eating berries flown in from South America or tomatoes grown in greenhouses in January,” Willett says. “Those have very big environmental impacts and greenhouse gas production.”

You’ve probably heard about eating locally and in season, but sometimes this isn’t a perfect system either. Willett recommends looking not just at the distance your food has traveled, but also at the transportation involved, especially when it comes to fruits and veggies.

“There’s no single factor that captures all of this. Local has value, but not all local is the best sometimes,” Willett says. “Driving a truck in from 100 miles away is relatively local but may have much more adverse environmental impact than bringing some fruits [in from] several hundred miles away by train in large amounts.”

Additionally, it may be worth it to think about your region and the stress that certain types of foods have on the local environment, both in the cases of animal-produced food and plant-based food.

“There’s big differences in water use for producing dairy, milk, in California versus Wisconsin, right?” says Heller. “Not only because there’s water shortages in California so they don’t get enough rain so it requires more irrigation, but also because the region is under water stress. Using that irrigation water in those regions is much more impactful both for environmental systems as well as other users of the water.”

Eating right for the environment is certainly enough to make your head spin, but the moral of the story is reducing the amount of meat (especially red meat) and thinking twice about where your favorite foods come from and how they got there is a pretty good start.