Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Vegan diets healthier for planet, people than meat diets

18.04.2006


The food that people eat is just as important as what kind of cars they drive when it comes to creating the greenhouse-gas emissions that many scientists have linked to global warming, according to a report accepted for publication in the journal Earth Interactions.



Both the burning of fossil fuels during food production and non-carbon dioxide emissions associated with livestock and animal waste contribute to the problem, the University of Chicago’s Gidon Eshel and Pamela Martin wrote in the report.

The average American diet requires the production of an extra ton and a half of carbon dioxide-equivalent, in the form of actual carbon dioxide as well as methane and other greenhouse gases compared to a strictly vegetarian diet, according to Eshel and Martin. And with Earth Day approaching on April 22, cutting down on just a few eggs or hamburgers each week is an easy way to reduce greenhouse-gas emissions, they said. "We neither make a value judgment nor do we make a categorical statement," said Eshel, an Assistant Professor in Geophysical Sciences.


"We say that however close you can be to a vegan diet and further from the mean American diet, the better you are for the planet. It doesn’t have to be all the way to the extreme end of vegan. If you simply cut down from two burgers a week to one, you’ve already made a substantial difference."

The average American drives 8,322 miles by car annually, emitting 1.9 to 4.7 tons of carbon dioxide, depending on the vehicle model and fuel efficiency. Meanwhile, Americans also consume an average of 3,774 calories of food each day.

In 2002, energy used for food production accounted for 17 percent of all fossil fuel use in the United States. And the burning of these fossil fuels emitted three-quarters of a ton of carbon dioxide per person. That alone amounts to approximately one-third the average greenhouse-gas emissions of personal transportation. But livestock production and associated animal waste also emit greenhouse gases not associated with fossil-fuel combustion, primarily methane and nitrous oxide.

"An example would be manure lagoons that are associated with large-scale pork production," Eshel said. "Those emit a lot of nitrous oxide into the atmosphere."

While methane and nitrous oxide are relatively rare compared with carbon dioxide, they are--molecule for molecule--far more powerful greenhouse gases than carbon dioxide. A single pound of methane, for example, has the same greenhouse effect as approximately 50 pounds of carbon dioxide.

In their study, Eshel and Martin compared the energy consumption and greenhouse-gas emissions that underlie five diets: average American, red meat, fish, poultry and vegetarian (including eggs and dairy), all equaling 3,774 calories per day.

The vegetarian diet turned out to be the most energy-efficient, followed by poultry and the average American diet. Fish and red meat virtually tied as the least efficient.

The impact of producing fish came as the study’s biggest surprise to Martin, an Assistant Professor in Geophysical Sciences. "Fish can be from one extreme to the other," Martin said. Sardines and anchovies flourish near coastal areas and can be harvested with minimal energy expenditure. But swordfish and other large predatory species required energy-intensive long-distance voyages.

Martin and Eshel’s research indicated that plant-based diets are healthier for people as well as for the planet.

"The adverse effects of dietary animal fat intake on cardiovascular diseases is by now well established. Similar effects are also seen when meat, rather than fat, intake is considered," Martin and Eshel wrote. "To our knowledge, there is currently no credible evidence that plant-based diets actually undermine health; the balance of available evidence suggests that plant-based diets are at the very least just as safe as mixed ones, and most likely safer."

In their next phase of research, Eshel and Martin will examine the energy expenditures associated with small organic farms, to see if they offer a healthier planetary alternative to large agribusiness companies. Such farms typically provide the vegetables sufficient to support 200 to 300 families on plots of five to 10 acres.

"We’re starting to investigate whether you can downscale food production and be efficient that way," Martin said.

Steve Koppes | EurekAlert!
Further information:
http://www.uchicago.edu

More articles from Studies and Analyses:

nachricht Researchers simplify tiny structures' construction drip by drip
12.11.2018 | Princeton University, Engineering School

nachricht Mandibular movement monitoring may help improve oral sleep apnea devices
06.11.2018 | Elsevier

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>