Vegetarian and “Healthy” Diets Could Be More Harmful to the Environment

Phionah Musumba
Posted December 16, 2015 from Kenya

Carnegie Mellon Study Finds Eating Lettuce Is More Than Three Times Worse in Greenhouse Gas Emissions Than Eating Bacon By Shilo Rea / 412-268-6094 / shilo@cmu.eduContrary to recent headlines — and a talk by actor Arnold Schwarzenegger at the United Nations Paris Climate Change Conference — eating a vegetarian diet could contribute to climate change. In fact, according to new research from Carnegie Mellon University, following the USDA recommendations to consume more fruits, vegetables, dairy and seafood is more harmful to the environment because those foods have relatively high resource uses and greenhouse gas (GHG) emissions per calorie. Published in Environment Systems and Decisions, the study measured the changes in energy use, blue water footprint and GHG emissions associated with U.S. food consumption patterns. Bacon and Lettuce Eating lettuce is more harmful to the environment than eating bacon.

“Eating lettuce is over three times worse in greenhouse gas emissions than eating bacon,” said Paul Fischbeck, professor of social and decisions sciences and engineering and public policy. “Lots of common vegetables require more resources per calorie than you would think. Eggplant, celery and cucumbers look particularly bad when compared to pork or chicken.” Fischbeck, Michelle Tom, a Ph.D. student in civil and environmental engineering, and Chris Hendrickson, the Hamerschlag University Professor of Civil and Environmental Engineering, studied the food supply chain to determine how the obesity epidemic in the U.S. is affecting the environment. Specifically, they examined how growing, processing and transporting food, food sales and service, and household storage and use take a toll on resources in the form of energy use, water use and GHG emissions. On one hand, the results showed that getting our weight under control and eating fewer calories, has a positive effect on the environment and reduces energy use, water use and GHG emissions from the food supply chain by approximately 9 percent. However, eating the recommended “healthier” foods — a mix of fruits, vegetables, dairy and seafood — increased the environmental impact in all three categories: Energy use went up by 38 percent, water use by 10 percent and GHG emissions by 6 percent. “There’s a complex relationship between diet and the environment,” Tom said. “What is good for us health-wise isn’t always what’s best for the environment. That’s important for public officials to know and for them to be cognizant of these tradeoffs as they develop or continue to develop dietary guidelines in the future.” CMU’s Steinbrenner Institute for Environmental Education and Research and the Colcom Foundation funded this research.

Comments 9

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Liz Poulsen
Dec 17, 2015
Dec 17, 2015

Hi Phionah - 

This is really interesting to me, as I have read a lot of research about how a vegetarian diet is really environmentally friendly, and I have changed my own diet accordingly. I notice that this article doesn't mention beef or dairy.

Would you please post the original source that this content came from? I'd be really interested in learning more about this research.

Thanks!

Liz

Phionah Musumba
Dec 19, 2015
Dec 19, 2015

Hey Liz, Thank you for taking the time to read and comment on this article. I would really love to provide more information, but I posted the article as it was. Nothing was added or removed. I want to believe that you would be able to find more information by clicking on the link within the article. Thanks again.

Best regards,

Liz Poulsen
Dec 19, 2015
Dec 19, 2015

Hi Phionah - 

I found a link to an original article: http://www.cmu.edu/news/stories/archives/2015/december/diet-and-environm... But unfortunately, you have to pay to see the full study. Oh well!

I'm still very suspicious of the fact that beef was not mentioned in this article...there are many ways that research findings can be manipulated and I think this is one example! I think it is unlikely that a vegetarian diet would be more harmful that a diet than includes beef and dairy products. Thanks for sharing, you've made me very curious about this research :)

Liz

Phionah Musumba
Jan 09, 2016
Jan 09, 2016

Hey Liz, You made me more curious too. I followed your link and hit the same snag. Am hoping that we will keep our eyes open and feelers out for when the whole study is shared.

Thanks for sharing.

Nusrat Ara
Dec 21, 2015
Dec 21, 2015

"What is good for us health-wise isn’t always what’s best for the environment. "

True. What we need is balance, a healthy balance for that .

Phionah Musumba
Jan 09, 2016
Jan 09, 2016

I am totally with you on this one, Nusrat. Thanks for your comment.

bgebstadt
Dec 21, 2015
Dec 21, 2015

Hi Phionah,

Thanks for raising this issue.

I was looking for articles that may elaborate on this study when I came across this article in Scientific American which discusses the concept of resources per calorie (including waste ). This article clarifies some of the research and methods from the original article. It is worth looking at to look at the concept of resources to produce food based on a per calorie perspective and the consideration of waste, excess, fragile foods, water intensive, etc. The article can be found at:

http://www.scientificamerican.com/article/lettuce-produces-more-greenhou...

Thanks for raising the issue about the resources necessary to grow/raise/develop food. It is a complicated topic in balancing what is good for the environment (and hence climate), human health and culture. At least from what I see in the US these three things (environment, human health and culture) are often in conflict with one another.

Phionah Musumba
Jan 09, 2016
Jan 09, 2016

Hello bgebstadt,

Thanks a lot for taking the time to read, comment and even provide more resources to expound on the same article.

In Africa, environment, human health and culture are always in conflict with each other.

Thanks again.

Maya Norton
Feb 02, 2016
Feb 02, 2016

Hello Friends,

Glad to have just learned of and joined this group.

There's no way that meat consumption is more environmentally friendly than eating the fruit of the earth (literally). Meat production, that is to say the raising and slaughtering of animals for human consumption, is incredibly damaging to the vitality of the land and water supply, not to mention the animals' own welfare. 

Here's one article. There are a multitude more, just google "environmental consequences of meat consumption," or some version thereof. 

https://sustainabletable.org.au/Hungryforinfo/Theenvironmentalimpactsofe...

~ Maya

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