In Conversation

Rate the plates: serving up info on the environmental impact of food

What’s better for the planet, quinoa or kale salad? Yale College seniors Gemma Shepherd and Addison Luck are letting their fellow students find out.
Addison Luck and Gemma Shepherd

Addison Luck and Gemma Shepherd (Photo credit: Dan Renzetti)

Later this month, you might spot Yale College seniors Gemma Shepherd and Addison Luck plastering dining halls around campus with posters about some ingredients often in the news: greenhouse gases.

It’s part of an effort endorsed by both Yale Hospitality and the Office of Sustainability to inform students about the environmental footprint of food items on the menu. The posters will provide detailed information about the carbon dioxide (e) emissions (this includes other greenhouse gases such as methane) associated with main ingredients in each dish, from mashed sweet potatoes to turkey meatloaf.

Luck and Shepherd ran a pilot version of the program at Pierson College last year and found that students care about the degree to which their food choices affect the environment.

YaleNews talked with Shepherd and Luck about the project. Interview condensed and edited.

What prompted this work?

Shepherd: Addison and I took (Tweedy-Ordway Professor of Environmental Health and Political Science) John Wargo’s class on “Global Food Challenges” last semester, and one week of the class was devoted to the carbon impacts of different foods. I remember we were in the dining hall eating lunch before section one day and I thought it would be so helpful if Yale Dining provided rankings of each of their food items, and from there the idea grew. I don’t think the connection between what we eat and the environment is an obvious one, but the impact of our diets is huge.

Honestly, I think carbon-impact ratings should be a requirement for all foods. It provides transparency and allows people to make informed decisions. A college campus, where people are eating every meal for up to four years, is a perfect place to try out this sort of project.

What role did Yale Hospitality and Yale’s Office of Sustainability play?

Luck: Allison Arnett, wellness manager of Yale Hospitality, really supported the project and its goals, and gave us the OK (along with a few others) to run the pilot in Pierson.

The Office of Sustainability has similarly been very helpful and has provided great feedback and help with poster designs, CO2 calculations, and manpower for the surveys. Additionally, we have received awesome guidance and inspiration from John Wargo and Robert Klee from the School of Forestry and Environmental Studies, Dr. Marney White from the School of Public Health and School of Medicine, and Grant Calderwood, an Ezra Stiles residential fellow.

What did you learn from the pilot program?

Luck: We surveyed 220 students and learned two valuable things: First, 76% of those students said that seeing the high environmental impact of certain foods, such as beef, lamb, and cheese, made them reconsider eating those foods.

Second, 91% of students reported that they would like to continue seeing environmental impact ratings in the dining halls. Considering the disproportionately large environmental impact of meat and other animal products, and the fact that America has one of the highest rates of per capita meat consumption in the world, these findings are super inspiring.

What goes into assessing the environmental footprint of specific meals?

Shepherd: If you wanted to do a complete environmental footprint there are many aspects to consider: greenhouse gas (GHG) emissions like CO2 and methane, land use change, water use, pesticide use, and ecotoxicity are some of the biggest concerns.

For our project we only looked at GHG emissions, as this is an important factor in the current climate crisis. For each entrée, we used a global systematic review of GHG emissions in order to determine the average kilograms of GHGs released, per serving size, of the production of the top ingredients in one meal.

What are some examples, understanding that lower figures are more eco-friendly than higher figures?

Luck: We converted the pounds of produce per 25 servings into kilograms. Then we multiplied the kilograms of produce times the kilograms of carbon dioxide (e) released per kilogram of produce.

For quinoa, the figure is 5.22 CO2e kg per 25 servings, or .209 kg per serving. For vegan gumbo, it’s 22.86 kg per 25 servings, or .914 per serving. For turkey meatloaf mesquite, it’s 41.46 kg per 25 servings, or 1.66 kg per serving.

How will you determine the impact of the rankings?

Luck: Our basic goal with this project is to help educate the campus on the varying impact our food choices have on the planet. We will be surveying students in the dining hall for one week before introducing the environmental impact posters, as well as during one week with the posters. If our results from this larger round of the project are as promising as the pilot, we believe Yale Hospitality will consider providing environmental impact rankings full-time, for every meal. We also hope this information will stay with students for the rest of their lives.

What are your go-to entrees at Yale?

Luck: My go-to entrees at Yale are any and all dishes that have beans and tasty veggies, and Yale Dining makes some mean lentil dishes.

Shepherd: I have been shifting my diet to a more plant-based one for several years now, but this project, the climate crisis, and some interesting health science behind plant-based diets inspired me to cut out all animal products. I’m a big fan of lentils, and some of the lentil dishes at Yale are delicious. I also love the hummus, some of the meat substitutes, the bean burgers, the vegan pancakes, and loads of the vegetables are really tasty too.

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