The Environmental Working Group released a study and subsequent guide illustrating how the proteins we most commonly consume rank in environmental impact.
When most people hear the term “carbon footprint” they immediately think of automobiles and the greenhouse gasses emitted from them. Many people do not consider the carbon footprint of the foods that supply supermarkets all over the world. A recent study by the Environmental Working Group (EWG) ranks our favorite sources of protein in terms of carbon emissions.
The study conducted by the Environmental Working Group and CleanMetrics, an environmental analysis firm, began with analyzing lifecycle assessments on the 20 most popular varieties of protein, including dairy and vegetable proteins. The study looked at the greenhouse gas emissions that are produced when that food is raised, processed, transported, cooked, and finally disposed of. There are variables to be considered when conducting such a study such as the fertilizers, pesticides, feed and grain, etc. that are being used to cultivate and produce meats and proteins. This study attempted to take these variables into consideration.
It should be noted that the study only gauged conventionally raised meat—animals that had been fed non organic grain and were raised in intensive systems typical to conventional animal farming. The carbon footprint illustration provided does not consider meat that was grass-fed, or pasture raised meats. All vegetable proteins in the study were likewise grown using conventional, non-organic methods.
The study results were surprising on some fronts, and expected on others. For example, beef is widely accepted as having a high carbon footprint; however cheese, which ranked number three, is not. In terms of methane (CH4) and carbon dioxide (CO2) emissions, lamb, beef and cheese ranked in the top three highest carbon footprint.
Pounds of CO2 Per Kilo of Protein
- lamb = 86.4lbs
- beef = 59.6lbs
- cheese = 29.7lbs
The study also showed that discarded leftovers of these proteins may account for 20% of the emissions associated with their production functions. One more reason why cooking only what you need and composting or recycling packaging is an important way to help reduce your dietary carbon footprint.
The 20 proteins studied are illustrated in the article Eat Smart: Your Food Choices Affect the Climate
, which offers a graph that measures the carbon footprint of the proteins in comparison to car miles driven per 4 ounces of each protein consumed.
For example, the protein with the lowest carbon footprint, lentils, equals less than one car mile driven per 4 ounces consumed; whereas the highest protein, lamb, equals greater than 7 car miles driven per 4 ounces consumed. Falling in the middle are proteins such as chicken, fish, eggs, nuts, rice, etc. Each of these popular middle menu items equal less than 3 car miles driven per 4 ounces consumed, making them a more environmentally friendly protein option than lamb, beef, pork, and cheese.
There are a number of ways that you can help reduce your carbon footprint. Other than going strictly organic and vegan, one popular method is “Meatless Mondays” where you take a pledge to skip meaty menu items for one day per week. True, this will not eliminate your carbon footprint, but it will help as you join thousands of others who have done the same. Here are some other comparisons of how the carbon footprint of an automobile stacks up against meaty meals, and what you can do:
- Eat one less burger per week = taking a car off the road for 320 miles
- A family of four skips meat and cheese one day a week = taking a car off the road for five weeks
- A family of four eats one less steak per week = taking a car off the road for almost three months
- Every individual in the United States skips meat and cheese one day per week = taking 7.6 million cars off the road