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
TEXT SIZE - +

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

Video Pope Francis Hopes Dual Canonizations Will Reconcile Church

John the XXIII and John Paul II will be made saints in a ceremony at St. Peter’s Square on April 27 More

Thailand Reacts to Plots Targeting Israelis

Authorities hope arrest of two Lebanese suspects will disrupt plot to attack young Israeli tourists More

Video In Capturing Nature's Majesty, Film Makes Case for Its Survival

'Once Upon a Forest' takes viewers deep into heart of tropical rainforest 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.
Pope Francis Hopes Dual Canonizations Will Reconcile Churchi
|| 0:00:00
...
 
🔇
X
Jerome Socolovsky
April 22, 2014 4:14 PM
On April 27, two popes - John the XXIII and John Paul II - will be made saints in a ceremony at St. Peter’s Square. VOA religion correspondent Jerome Socolovsky says the dual canonization is part of the current pope’s program to reconcile liberals and conservatives in the Roman Catholic Church.
Video

Video Pope Francis Hopes Dual Canonizations Will Reconcile Church

On April 27, two popes - John the XXIII and John Paul II - will be made saints in a ceremony at St. Peter’s Square. VOA religion correspondent Jerome Socolovsky says the dual canonization is part of the current pope’s program to reconcile liberals and conservatives in the Roman Catholic Church.
Video

Video In Capturing Nature's Majesty, Film Makes Case for Its Survival

French filmmaker Luc Jacquet won worldwide acclaim for his 2005 Academy Award-winning documentary "March of the Penguins". Now Jacquet is back with a new film that takes movie-goers deep into the heart of a tropical rainforest - not only to celebrate its grandeur, but to make the case for its survival. VOA's Rosanne Skirble reports.
Video

Video Boston Marathon Bittersweet for Many Runners

Monday's running of the Boston Marathon was bittersweet for many of the 36,000 participants as they finished the run that was interrupted by a double bombing last year. Many gathered along the route paid respect to the four people killed as a result of two bombings near the finish line. VOA's Carolyn Presutti returned to Boston this year to follow two runners, forever changed because of the crimes.
Video

Video Pacific Rim Trade Deal Proves Elusive

With the U.S.-led war in Iraq ended and American military involvement in Afghanistan winding down, President Barack Obama has sought to pivot the country's foreign policy focus towards Asia. One aspect of that pivot is the negotiation of a free-trade agreement among 12 Pacific Rim nations. But as Obama leaves this week on a trip to four Asian countries he has found it very difficult to complete the trade pact. VOA's Ken Bredemeier has more from Washington.
Video

Video Robotic Mission Kicks Up Lunar Dust

A robotic mission to the moon was deliberately crashed onto the lunar surface late last week, but not before scientists had collected data gathered by the spacecraft which was designed to self-destruct. VOA's Rosanne Skirble reports on the preliminary findings of the craft, called LADEE - an acronym for Lunar Atmosphere and Dust Environment Explorer.
Video

Video Boko Haram Claims Responsibility for Bombing in Nigerian Capital

The Nigerian militant group known as Boko Haram has claimed responsibility for a bombing in the capital on April 14th that killed 75 people. In the video message, Abubakar Shekau, the man who says he ordered the bombing, says nothing about the mass abduction of more than 100 teenage girls, most of whom are still missing. Heather Murdock has more for VOA from Abuja.
Video

Video Ukraine Developments Hang Over Obama Trip to Asia

President Barack Obama's trip to Asia this week comes as concerns over Beijing's territorial ambitions are growing in the region. Those concerns have been compounded by Russia's recent actions in Ukraine and the possibility that Chinese strategists might be looking to Crimea as a model for its territorial disputes with its neighbors. VOA's Bill Ide has more from Beijing.
Video

Video Autistic Adults Face Housing, Job Challenges

Many parents of children with disabilities fear for the future of their adult child. It can be difficult to find services to help adults with disabilities - physical, mental or emotional - find work or live on their own. The mother of an autistic boy set up a foundation to advocate for the estimated 1.2 million American adults with autism, a developmental disorder that causes communication difficulties and often social difficulties. VOA's Faiza Elmasry reports.
AppleAndroid