The food we consume has an environmental impact, often called a carbon footprint. Food systems contribute significantly to global greenhouse gas emissions, estimated at 26% to 33% of the total. Even a simple BLT sandwich contributes to these emissions throughout its production. This article examines the environmental cost of a BLT, its components, and how its footprint is calculated.
The Carbon Footprint of BLT Ingredients
Each BLT component contributes differently to its carbon footprint, with some ingredients having a notably higher impact. Bacon, from pork, typically carries the largest environmental burden. Raising pigs is resource-intensive, requiring significant land and water for feed and generating emissions from manure. Pork is considered one of the top greenhouse gas-generating animal products, with bacon having a carbon footprint of around 7.03 kg of CO2 equivalent per kilogram. A 30-gram serving accounts for approximately 330 grams of CO2 equivalent.
Plant-based ingredients generally have lower carbon footprints. Lettuce has a relatively low impact, ranging from 0.26 kg to 0.57 kg of CO2 equivalent per kilogram, with over 82% of emissions from growing resources like pesticides, water, and land. Tomatoes have a more variable footprint depending on cultivation. Field-grown tomatoes produce about 80 kg of CO2 per ton, while those from heated greenhouses can emit up to 700 kg per ton. This difference highlights how production methods influence environmental impact.
Bread also contributes to the sandwich’s footprint, generating between 0.5 kg and 1.24 kg of CO2 equivalent per loaf. A major portion of its emissions, about 43%, comes from the energy-intensive production of fertilizers used in wheat cultivation. Mayonnaise also adds to the footprint, with its impact tied to ingredients like eggs and oils. Its carbon footprint can range from 1.17 kg to 2.70 kg of CO2 equivalent per kilogram, largely due to egg farming.
How Emissions Are Calculated
Calculating food’s environmental impact uses a Life Cycle Assessment (LCA). This comprehensive methodology evaluates a product’s entire journey, from “farm-to-fork,” by quantifying greenhouse gas emissions at each stage. This begins with agricultural practices, including emissions from land use, fertilizer production, and livestock methane.
The assessment then moves to processing, including energy consumed in factories for activities like cleaning, heating, and mixing ingredients. Transportation also plays a role, accounting for fuel used to move products from farms to facilities and then to retail. Packaging materials, from production to manufacturing, add to the overall footprint.
Beyond production and distribution, LCA considers emissions from retail operations, including refrigeration, and food waste disposal. Decomposing food in landfills generates methane, a potent greenhouse gas. All greenhouse gases are converted into carbon dioxide equivalents (CO2e) for standardized comparisons. These complex calculations rely on various assumptions and averages, leading to some variability in reported figures.
Putting the BLT’s Carbon Footprint in Perspective
The estimated carbon footprint of a typical BLT sandwich provides a tangible example of food-related emissions. A ready-made BLT has been estimated to release approximately 1,007.4 grams of carbon dioxide equivalent (CO2e). For context, consuming one BLT daily for a year could generate emissions comparable to driving a car from New York to Chicago. For instance, a breakfast sandwich with eggs, bacon, and sausage can have a carbon footprint up to 1,441 grams of CO2e, roughly equivalent to a car driving 12 miles.
Meat and dairy products generally have a much higher carbon footprint than plant-based foods. Beef, for example, generates around 60 kg of CO2e per kilogram, while plant-based options like peas emit only about 1 kg per kilogram. Carbon emissions from most plant-based products are often 10 to 50 times lower than animal-based products. This highlights that the type of food consumed has a far greater influence on its carbon footprint than its travel distance.
Reducing Your Food’s Environmental Impact
Changing dietary habits can significantly reduce an individual’s food-related carbon footprint. Moderating meat consumption, especially red meat, is one of the most effective ways to lower emissions. Shifting towards more plant-based meals can lead to substantial reductions in greenhouse gas emissions.
Minimizing food waste is another powerful action. A substantial amount of food is wasted globally, leading to unnecessary resource depletion and greenhouse gas emissions. Simple practices like meal planning, proper storage, and using leftovers prevent food from ending up in landfills where it produces methane.
Choosing locally sourced and seasonal produce can contribute to a lower footprint, though “food miles” are often less significant than the food type or production method. For instance, greenhouse tomatoes can have a higher carbon footprint than field-grown tomatoes transported long distances. Supporting sustainable agricultural practices, like organic or regenerative farming, reduces synthetic fertilizer needs and improves soil health, further lowering emissions. Opting for less processed foods and reducing unnecessary packaging also contributes to a more environmentally conscious diet.