Carbon Menu Labeling Methodology
Sweetgreen is a mission-driven restaurant brand serving healthy food at scale and since day one, we’ve been dedicated to leading with purpose and making sustainable decisions that last longer than we will.
The sweetgreen sustainability team, in partnership with its enterprise climate platform, Watershed Technology, Inc. (Watershed), has calculated the greenhouse gas emissions associated with each item on our menu. The purpose of this document is to provide transparency as to the methodology our team uses to calculate these emissions1. This document details the current methodology used to calculate emissions, the data sources used to inform those calculations, and future improvements that we hope to make to further refine emissions estimates.
We are excited to share the emissions impact of our meals, and equally recognize that carbon measurement is an evolving practice. Over time we anticipate improvements in climate science, data availability (especially pertaining to the emissions factors we use to calculate emissions from each of our specific food products), and changes to the world generally (e.g., agricultural practices and growing conditions) to improve our understanding of emissions, and enable us to produce even more detailed and accurate estimations of the emissions of our meals. We will update our carbon calculations periodically to reflect these evolutions, and provide even more granular and accurate emissions impacts associated with sweetgreen meals.
The Sweetgreen Menu
At sweetgreen, we serve fresh, flavorful feel-good food. We cook with whole ingredients, and our menu is prepared fresh daily – free of artificial preservatives and stabilizers, and refined sugars. We have designed our menu to be delicious and convenient, to empower our customers to make healthier choices.
We currently offer signature salads, warm bowls, plates, and sides that are complemented by limited-time menu drops that feature in-season produce and customer-requested ingredients.
Salads consist of a greens base (romaine, kale, etc.), a protein (if applicable), toppings, crunches and dressings.
Our Warm Bowls are a heartier option that feature a half-grains (warm quinoa or wild rice) and half-greens base.
We currently serve sides such as rosemary focaccia sourced from local bakery partners across each of our markets, and roasted sweet potatoes, as well as seasonal limited-time side dishes.
We also recently added a Crispy Rice Treat as our first dessert.
In addition to our standard menu, we also typically serve geographic-specific items that differ across sweetgreen locations.
With Watershed, sweetgreen has calculated the emissions associated with each of these meals based on the average ingredient portions included in each meal. We’ve included additional detail below on the specific methodologies used.
Sweetgreen regularly engages with its ingredients suppliers about their sourcing and harvesting practices and prioritizes transparency in the food it provides to its customers. We leverage this information to engage our existing suppliers in discussions aimed at helping them improve their sustainability practices and use similar questionnaires to assess potential suppliers. Both of these efforts are designed to ensure that we’re continuing to work towards a future where all of the ingredients in sweetgreen’s meals continue to be high quality and delicious, while generating fewer emissions across their lifecycle.
Sweetgreen has calculated the emissions associated with its menu items in kilograms (kg) of carbon dioxide equivalent (CO₂e). Our calculations reflect the total greenhouse gas emissions (including carbon dioxide, methane, nitrous oxide, and greenhouse gasses) associated with the production of each ingredient. Other greenhouse gasses were converted to carbon dioxide equivalents in accordance with global warming potential values provided in the Fifth Assessment Report (AR5) by the Intergovernmental Panel on Climate Change (IPCC).
For each menu item, we have calculated the cradle-to-grave emissions associated with each individual ingredient. This includes emissions from producing feed for animals, direct emissions (e.g., nitrous oxide emitted from crop fertilizer), land use change (e.g., emissions from clearing forest to make arable land) and other product-related emissions, including end-of-life treatment (e.g., disposal)2. The per-item emissions provided on menus do not include emissions from operating sweetgreen locations, corporate operations, or transportation of products and ingredients3. These emissions are included in sweetgreen’s corporate carbon footprint, which is measured separately.
The menu carbon calculator is designed to calculate the carbon footprint of menu items (e.g., salads and bowls). Emissions figures associated with each meal are based on standard portions for each individual ingredient and dressing. The actual carbon footprint of every meal might slightly differ as there are minor deviations when a meal is made fresh from scratch in our restaurants every day. Further, substitutions, additions, and omissions made by customers of certain ingredients will impact the carbon footprint of any menu item and are not included in the calculations.
To calculate emissions from each meal, we multiply the weight of each ingredient in the meal by the ingredient’s associated emissions factors, to derive the carbon footprint of each individual ingredient in the meal. We then aggregate all of the ingredients in a meal to calculate the total carbon footprint of that meal4. We use a variety of sources for our emissions factors, and have selected sources that we feel most accurately represent the emissions associated with each ingredient based on available information. Sources for our emissions factors include: ecoInvent (v 3.8), Agribalyse®, Poore and Nemecek (2018), and ESU. As sources update their emissions factors, we will periodically update emissions on sweetgreen’s menu to reflect the latest versions. As referenced in ‘The Sweetgreen Menu’ section, for specific ingredients (chicken, cheese & seafood) we use information provided by our suppliers on their farming and harvesting practices to develop a more nuanced understanding of their emissions, which enables us to develop custom emissions factors for those specific ingredients, and be more transparent about the ingredients we include in our meals5. The emissions factors of various suppliers for the same ingredient are then translated into one number via a weighted average6.
We have elected to use sources for our emissions factors (outlined above) which we feel accurately capture the emissions associated with each individual sweetgreen ingredient. Other sources publish emissions factors for the same ingredients, and there may be some discrepancies in how each source calculates their specific emissions factors. We have attempted to reconcile differences by choosing sources with similar methodologies, but recognize that methodological differences will continue to exist depending on sources used. However, it’s important to note that we have intentionally chosen emissions factor sources that result in conservative estimates to ensure we do not undercount the carbon emissions from our ingredients.
Emissions from the average American meal
Included on sweetgreen’s online menu is a reference to the average range of emissions associated with the average American meal. The average American meal emits between 1.9 - 3.4 kg CO2e. We’ve included this range to help contextualize the emissions associated with sweetgreen meals, but not as a direct comparison given that the methodologies, while similar, are not exactly the same. We calculated the range of per capita emissions per American meal by leveraging several published academic studies that calculated the average per capita emissions from food consumption per day, and then dividing by three, to account for three meals in a day. For this range, we selected studies with methodologies similar to those that we used to measure the emissions on our menu (e.g., cradle-to-consumer). The range reflects the high and low estimates from these peer-reviewed studies7.
Climate science is continually evolving with improvements in methodology and granularity, and thus our menu calculator will also continually improve. Our aim is to inform our customers, as reliably as possible given the methodology available to us, of the carbon impact of their choices when eating at sweetgreen. Ine future, we seek to make the following improvements:
Increase the specificity of our emissions factors by encouraging our suppliers to provide granular emissions data. For ingredients where we have not received granular emissions data, we continue to use emissions factors based on industry averages.
Further increase the granularity of our estimate for average per capita emissions per meal in the United States by monitoring for the release of other published, credible studies that enable us to refine our point of reference.
1Different companies may calculate emissions differently. Emissions provided by sweetgreen are not meant to be used for comparison between different brands.
2Emissions factors include emissions from: food production, land use change, and emissions from production (e.g., embedded carbon) upstream of sweetgreen. Emissions factors pertain to raw ingredients rather than cooked ingredients, with the exception of wild rice & quinoa. For wild rice & quinoa, emissions factors pertain to cooked grains and take water content into consideration.
3On-menu emissions labels do not include emissions from packaging, food preparation, cooking, labor, logistics, or overhead, as these categories are calculated separately in our corporate carbon footprint.
4The carbon number for each menu item assumes a light serving size of dressing (30g) and no bread. Adding a piece of bread increases the emissions of a bowl by 0.045 kg co2e.
5Answers to surveys are self-reported by suppliers and not audited by sweetgreen or its climate enterprise platform providers.
6Weighted average emissions factors are determined based on supply allocation at a given point in time and are subject to change based on market factors
7Jones and Kammen (2011) estimate 5.6 kg CO2e / day (calculated as 1.9 kg CO2e / meal) and Boehm et al. (2018) estimated 10.3 kg CO2e / day (calculated as 3.4 kg CO2e / meal)