Cows emit greenhouse gases, so what does this mean for beef lovers’ diets?

From her home in eastern Nebraska, Angie O’Brien is doing what she can to protect the environment.

She reduces, reuses and recycles, even taking the time to clean dirty items like peanut butter jars so they can be recycled.

“My husband is always like, ‘You’re wasting water. Throw it away!'” she says. “I’m like, ‘I know, but I think it’s a good thing.'”

O’Brien also tries to know where her food comes from: For example, she often buys her beef from a local rancher.

“I’ve always wanted to be more conscious of where my beef comes from,” O’Brien says, “and I thought if it was local, grass-fed, pasture-raised, it’d be a little better than something that’s been taken to a feedlot and fattened up.”

Beef, in particular, can increase the human contribution to climate change. In the United States, beef production is Approximately 4% According to the U.S. Department of Agriculture, it is one of the nation’s top global warming pollutants.

Some researchers and environmentalists have suggested that eating less beef could help reduce emissions. A study According to a study published in the American Journal of Clinical Nutrition, substituting beef for a meal can cut your daily food intake in half.

But O’Brien, from Nebraska, doesn’t plan on cutting out red meat completely.

“No,” she said, laughing, “we’re in the beef state!”

The Emissions Footprint of Beef

Diego Rose, director of the nutrition program at Tulane University in New Orleans, says most people don’t think about how their diet affects the environment.

“They’re usually thinking about energy use,” he says. “Do you fly a lot? What kind of car do you drive? How often do you drive? Those questions take precedence over food and diet.”

But his study tallied the daily dietary emissions of about 17,000 people, and when he ran through the list, he found that most foods had roughly the same emissions.

“Then all of a sudden you find something that’s 10 times, maybe 100 times, more valuable than anything else,” he says, “and every time, it’s beef.”

Burgers, steaks and roasts have been added.

“If we could get the highest meat eaters to reduce their consumption to average levels, we could reduce greenhouse gas emissions so significantly,” Rose said, “that we could actually have a small impact on our original commitments to the Paris Agreement.”

Joshua Specht said beef’s cultural role in the US makes it a tough sell. In his book “Red Meat Republic: How Beef Changed America, From Hoof to Plate,” he argues that beef is associated with American pioneering, affluence and masculinity.

“Beef consumption is at the core of what it means to be American. Ranching was central to the creation of America,” said Specht, the Notre Dame professor. “Whenever we talk about meat consumption today, it’s all in the hamburger that we take a bite of.”

Burping increases gas emissions

Cow burps have a huge impact on the environment, according to Aaron Smith, an agricultural economist at the University of California, Berkeley.

“Some people say they’re cow farts because they’re fun and entertaining to talk about,” he says, “but in reality, they’re mostly burps.”

As cows break down grass and hay, they produce methane through digestion, a process that’s unique to animals like cows, sheep and goats; chickens and pigs have different digestive systems.

“That’s one of the reasons cows can digest foods that humans can’t,” Smith says. “If you eat coarse grass, it just goes straight into your digestive tract. But cows can break it down.”

The cows then burp methane, releasing a potent gas that contributes to climate change. Methane initially traps much more heat than carbon dioxide, but doesn’t stay in the atmosphere for long.

“It’s similar to how much heat comes from a campfire,” Smith says. “Methane is like a dry twig that burns very hot, so it produces a lot of heat in a short amount of time, whereas carbon is like a big log that burns steadily for a long time.”

Methane stays in the atmosphere for about 10 years, while carbon dioxide produced by burning fossil fuels can stay there for hundreds of years. But it traps more heat, even as scientists say emissions need to be sharply reduced to prevent the worst impacts of climate change.

Environmentally friendly beef farming

Some in the beef industry are thinking about how cattle affect the environment, including central Nebraska rancher Jim Knopic.

About 20 years ago, Nopic changed his ranching strategy when he decided he wanted to take better care of the land where his family had raised cattle and grown crops for four generations.

“What I really want is to give the next generation clean water, a good environment and good, clean food,” he said, checking on his cows one summer morning.

Nopic once practiced traditional grazing, in which ranchers would graze their cattle in large pastures for months at a time, but now he moves his herd to smaller areas of the pasture more frequently, sometimes as often as twice a day.

This is called “herd grazing” and the idea is that the cows help the soil by compacting organic matter on the ground, allowing the grass time to recover between grazing.

Knopic said he’s seen environmental benefits on his ranch: What was once dry and bare soil is now healthy pasture, with grass thriving despite years of drought that has withered pastures across Nebraska.

“It’s something I regret not doing sooner,” he said. “We’re raising cattle, helping the soil and growing grass at the same time.”

Most of Nopic’s cattle end up in feedlots, but some ranchers and researchers say forcing the cows to graze on grass for their entire lives could reduce the cattle’s overall impact on the environment.

Grass-fed beef

Tong Wang, a researcher at South Dakota State University, compared emissions from different beef production operations in North America.

Her research suggests that ranches like Nopic, which graze cattle for short periods and convert cropland to grass, could offset methane emissions by resequestering carbon in the soil.

Wang stressed that further research is needed.

“You have to consider not just the cow but the whole system the cow is in,” she says. “Feedlots probably aren’t going to sequester carbon, but grass-fed systems could.”

The challenge, Wang acknowledges, is that cows eating only grass take longer to gain weight, which means they live longer and emit more methane gas.

“Strictly speaking, grass-fed cattle are not necessarily better for the environment from a greenhouse gas standpoint,” says Al Lotz, an agricultural engineer and researcher at the U.S. Department of Agriculture, “but there are real benefits to grass-fed cattle in terms of soil quality, electricity savings and water use.”

Lotz has spent about a decade studying the environmental impacts of the U.S. beef supply chain, and he said that ultimately, beef emissions will be difficult to significantly reduce.

He doubts whether carbon neutrality, which would mean all emissions from an operation are offset by an equal amount of removal, is achievable.

“There are lots of ways we can reduce carbon emissions by 5 to 10 percent, which is a good thing, meaning we need to do something,” Lotz said, “but to achieve a 50 percent reduction, or carbon neutrality, is a very difficult task.”

That’s why Diego Rose of Tulane University says the answer is simple.

“If you want to reduce your carbon footprint, eat less beef,” Rose says. “There are ways to make a change without giving up beef entirely. Anything you reduce or substitute will have an impact on the environment.”

For Angie O’Brien, cutting back on her beef intake seems more doable.

“I might cut back a little bit because I’m not eating beef every night,” she says. “I’m okay for a few days, but then I’m like, ‘Oh, a burger sounds so good.'”

This story begins: Harvest Public MediaA collaboration of Midwest public media newsrooms covering food systems, agriculture and rural issues.