News / Health

Online Tool Shows How What You Eat Affects Pollution

Reducing animal protein consumption cuts nitrogen pollution.
Reducing animal protein consumption cuts nitrogen pollution.

Multimedia

Audio

Looking to lead a more eco-friendly lifestyle? You could start by cutting back on meat. A new nitrogen footprint calculator shows you the impact your diet has on the environment.  

You may have heard of the concept of a carbon footprint. That's how much of the greenhouse gas carbon dioxide your lifestyle generates. Now researchers have developed a way to measure how our lifestyle - and in particular our diets - impacts another major source of climate-changing pollution: nitrogen.

Everything needs nitrogen, from plants to plankton to people. It's a key element in the proteins that make up our bodies.

Good news, bad news

In the early twentieth century, scientists figured out a way to take nitrogen out of the air and turn it into a form that plants could use. The invention of synthetic nitrogen fertilizer dramatically improved food production.

"That's the good news," says environmental sciences professor Jim Galloway at the University of Virginia. "We're able to feed the world's population because of this wonderful invention."

The bad news, Galloway says, is that many parts of the world use far too much nitrogen fertilizer. Burning fossil fuels also creates nitrogen pollution. Galloway says the excess nitrogen "contributes to smog, acid rain, loss of biodiversity, dead zones along the coast, global warming, stratospheric ozone depletion. The list is quite long."

Visualizing impacts

Galloway and his colleagues developed the nitrogen footprint calculator to show how people's behaviors contribute to that long list of environmental impacts.

The calculator starts with a graph showing the amount of nitrogen pollution produced by the average person. One of the first things you notice is that food is far and away the biggest contributor: 72 percent of the 42 kilograms the average American produces comes from food consumption. Housing, transportation and goods and services make up the rest.

To see exactly how your diet affects your nitrogen footprint, the calculator lets you adjust how many times a week you eat 16 different kinds of foods.

"As you change your consumption, you can see how the graph changes," says co-creator Allison Leach at the University of Virginia. "So as you scale down one bar, you can see your nitrogen footprint shrinking."

Too much protein

Americans eat far more protein on average than the U.S. Department of Agriculture recommends, Leach says. "Reducing your protein to the recommended levels is going to have a huge impact on reducing your nitrogen footprint. [That] reduces it by almost half."

Reducing the amount of animal protein is one of the quickest ways to shrink that footprint. Galloway says that's because feeding plants to animals is an inefficient use of nitrogen.

"For large animals like beef, a very large fraction of the nitrogen that enters the cow's mouth is excreted out the back end," he says.

Beef is less efficient than chicken or pork, while plant sources like legumes are the most efficient, Leach says.

Nitrogen footprints around the world

She and her colleagues also created nitrogen footprint calculators for Germany and the Netherlands. She says their footprints are smaller largely because they tend to eat less meat, not because of major differences in their farming practices.

"Industrialized agriculture production is pretty consistent among developed countries. But it's going to be very different in developing countries."

The next step, Leach says, is a nitrogen footprint calculator for India, a developing country where farming practices are very different from in the industrialized world.

Footprints growing

But even in the developing world, nitrogen footprints are changing. The world's population is not only growing, it's also growing richer. One consequence is that people are eating more animal protein. Galloway says they have looked at what the world might look like in 2050 - and it raises concerns.

"If the entire world had the per capita resource-use habits that people in North America have, then we would be putting three to four to five times more reactive nitrogen into the environment than we are now," he says. "And that's frankly untenable. Our ecosystems can't handle that."

Galloway says that’s why it’s so important that we all do a better job managing the amount of nitrogen we put on our fields, in our mouths, and into our environment.

You May Like

UN Watchdog Urges Israel to Probe Possible Gaza War Crimes

More than 2,100 Palestinians, most of them civilians, were killed in a 51-day war in Gaza, along with 67 Israeli soldiers and six civilians in Israel More

New Kenyan 'Thin SIMs' Poised to Transform African Mobile Money

Equity's new technology is approved in African nation for one-year trial, though industry leader Safaricom says thin SIMs could lead to data theft and fraud More

Solar's Future Looks Brighter

New technology and dropping prices are contributing to a surge in solar power More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Talks to Resume on Winter Gas for Ukrainei
X
Al Pessin
October 25, 2014 4:21 PM
Ukrainian and Russian officials will meet again next week in an effort to settle their dispute over natural gas supplies that threatens to leave Ukraine short of heating fuel for the coming winter. VOA’s Al Pessin reports from London the dispute is complex, and has both economic and geopolitical dimensions.
Video

Video Talks to Resume on Winter Gas for Ukraine

Ukrainian and Russian officials will meet again next week in an effort to settle their dispute over natural gas supplies that threatens to leave Ukraine short of heating fuel for the coming winter. VOA’s Al Pessin reports from London the dispute is complex, and has both economic and geopolitical dimensions.
Video

Video Smugglers Offer Cheap Passage From Turkey to Syria

Smugglers in Turkey offer a relatively cheap passage across the border into Syria. Ankara has stepped up efforts to stem the flow of foreign fighters who want to join Islamic State militants fighting for control of the Syrian border city of Kobani. But porous borders and border guards who can be bribed make illegal border crossings quite easy. Zlatica Hoke has more.
Video

Video China Political Meeting Seeks to Improve Rule of Law

China’s communist leaders will host a top level political meeting this week, called the Fourth Plenum, and for the first time in the party’s history, rule of law will be a key item on the agenda. Analysts and Chinese media reports say the meetings could see the approval of long-awaited measures aimed at giving courts more independence and include steps to enhance an already aggressive and high-reaching anti-corruption drive. VOA’s Bill Ide has more from Beijing.
Video

Video After Decades of Pressure, Luxembourg Drops Bank Secrecy Rules

European Union finance ministers have reached a breakthrough agreement that will make it more difficult for tax cheats to hide their money. The new legislation, which had been blocked for years by countries with a reputation as tax havens, was approved last week after Luxembourg and Austria agreed to lift their vetoes. But as Mil Arcega reports, it doesn’t mean tax cheats have run out of places to keep their money hidden.
Video

Video Kobani Refugees Welcome, Turkey Criticizes, US Airdrop

Residents of Kobani in northern Syria have welcomed the airdrop of weapons, ammunition and medicine to Kurdish militia who are resisting the seizure of their city by Islamic State militants. The Turkish government, however, has criticized the operation. VOA’s Scott Bobb reports from southeastern Turkey, across the border from Kobani.
Video

Video US ‘Death Cafes’ Put Focus on the Finale

In contemporary America, death usually is a topic to be avoided. But the growing “death café” movement encourages people to discuss their fears and desires about their final moments. VOA’s Jerome Socolovsky reports.
Video

Video Ebola Orphanage Opens in Sierra Leone

Sierra Leone's first Ebola orphanage has opened in the Kailahun district. Hundreds of children orphaned since the beginning of the Ebola outbreak face stigma and rejection with nobody to care for them. Adam Bailes reports for VOA about a new interim care center that's aimed at helping the growing number of children affected by Ebola.

All About America

AppleAndroid