Why Going Vegetarian Isn't Necessarily The Best Diet For The Planet

Giving up meat and dairy has been said to be the best thing you can do for the planet.

The climate impact of the two food groups is huge ― meat and dairy are responsible for 14.5% of all human-made greenhouse gas emissions. If people in wealthier countries like the U.S. don’t cut back on eating meat, climate analysts have said, we’re not going to be able to prevent dangerous levels of global warming.

For many people, making the full switch to a vegetarian or vegan diet can seem daunting. But this week brings some good news: You don’t have to forgo meat entirely to have a diet that is good for the planet.

New research published in the journal Global Environmental Change shows that if enough people adopt a mostly vegan diet that includes small amounts of animal products, it would go a long way toward reducing America’s climate emissions to where they need to be to help the planet avoid catastrophic levels of climate change.

“Much of the communication around the need to shift away from diets high in animal foods has resulted in people feeling like we all need to move towards a vegan diet,” said Keeve Nachman, an assistant professor at Johns Hopkins University and a co-author of the study. “It’s more nuanced than that.”

In fact, Nachman’s research found that limiting meat or dairy to once per day would actually have a lower carbon footprint than going vegetarian, which often involves multiple servings per day of eggs and dairy. That’s because of the sometimes overlooked climate impact of dairy products. Milk, cheese and other dairy products mostly come from cows, and cattle farming uses large amounts of land and resources. Cows also emit methane, a potent greenhouse gas.

Of course, the exact climate impact of a person’s diet very much depends on the individual, said Dr. Tara Garnett, a food and climate researcher who was not involved in the study. There’s a big difference between the kind of vegetarian diet where you have “eggs for breakfast, a large cheese sandwich for lunch and then maybe a quiche for dinner followed by ice cream,” she said, and the kind where you eat “toast for breakfast, a hummus sandwich for lunch and dhal with a dollop of yoghurt for dinner.”

Dairy has an “underappreciated climate footprint,” Marco Springmann of the University of Oxford, who has previously called for a tax on bacon and burgers, told HuffPost. “A vegetarian diet may not be a solution [to tackling climate change], of course, it always depends on the proportion, but if you eat high amounts of dairy it would have a high impact.”

Nachman said the research findings are not an attempt to provide dietary advice. But he hopes people will realize that making a difference with their food choices is perhaps not as difficult as they might have thought.

He said food writer Mark Bittman inspired the researchers to test the climate impact of continuing to eat small amounts of meat. Bittman adheres to what he calls a ‘vegan before 6’ diet, where he eats animal products during only one meal a day. He’s described it as a way of encouraging himself to eat more healthfully.

Nachman calls his version of this diet ― where animal products are only consumed once a day ― the “two-thirds vegan” diet.

“One of the greatest barriers to folks changing their diets is that it’s tough to reconcile that you are going to have to give something up for good and totally exclude it from your diet,” Nachman said. “I think it’s really exciting to see that people can include things in their diet, just at lower quantities, and still help work to our goals of reducing climate emissions significantly.”

While the study does not look at this directly, Nachman estimates that if the entire U.S. population adopted the two-thirds vegan diet, it would cut national climate emissions by approximately 6%.

The research acknowledges that poorer countries will see dietary emissions rise, as they need to consume more animal products to meet nutrition and hunger targets. This puts corresponding pressure on rich countries to reduce their overconsumption of meat and dairy.

Other meat reduction campaigners have welcomed the research, saying it will help people understand the many factors that determine the true impact of reducing meat consumption, such as where and how the meat was produced and what people eat instead.

“There are lots of other small steps people can take, like reducing portion sizes of meat or trying to incorporate more vegan meals throughout the week,” said Peggy Neu, president of Meatless Monday, an international campaign that encourages people not to eat meat on Mondays to improve their health and the health of the planet. “The most important thing is for people to find strategies that work for them, then build on it over time.”

Nachman said he hopes the findings will also influence future versions of the U.S. dietary guidelines, which are up for revision next year and which do not currently take environmental factors into account.

The guidelines have a major impact on Americans’ dietary habits, as they form the basis of federal nutrition programs, including nationwide school lunch and food assistance programs. They are also used to guide local, state and national health promotion and disease prevention initiatives.

Diets are important, but they can only do so much without more fundamental changes to our food system. A report published Monday by the Food and Land Use Coalition, for example, calls for governments to completely overhaul the $700 billion a year in subsidies that currently support climate-intensive animal farming.

For Nachman, though, his two-thirds vegan diet is a good place to start the debate. “These dietary scenarios and their corresponding environmental footprints can be the starting points for us working out how can we make [the two-thirds vegan diet] feasible from a nutritional, cultural point of view,” he said, “and shift our diets from a form today that is unsustainable to one that is not going to result in us spiraling into catastrophic climate change.”