Carbon Footprints: Vegan Proteins Vs. Animal Proteins
By Jeanne Yacoubou, MS
In our recent article on the carbon footprints of vegan vs. meat pizza, we relied on the average carbon emissions – expressed as kilograms of carbon dioxide equivalents – associated with the production of each pizza component, whether it be broccoli or bacon. These values were based in large part on the 2018 article by Poore & Nemecek titled Reducing food’s environmental impacts through producers and consumers.
Using estimates based on averages was the easiest way to deal with huge amounts of data from more than 38,000 farms in 119 countries. We cannot fault the investigators for choosing this way to present their findings.
However, a closer look at the data reveals major differences from farm to farm. We created a table that shows the wide variations – and which leads us to draw a few important conclusions that our pizza calculations don’t reveal. These numbers refer to the kilograms of CO2eq emitted per 100 grams of protein. The median (middle value in a range) is in the last column. This table is based on the graphical analysis by Our World in Data:
| Protein Source | Lowest kgCO2eq | Highest kgCO2eq | Median kgCO2eq |
| Beef | 9 | 105 | 25 |
| Pork | 4.5 | 14 | 6.5 |
| Chicken | 2.4 | 12 | 4.3 |
| Cheese | 4.5 | 14 | 8.4 |
| Tofu | 1.1 | 3.5 | 1.6 |
| Beans | 0.2 | 2.2 | 0.65 |
| Peas | 0.1 | 0.8 | 0.36 |
| Nuts | -2.2 | 2.4 | -0.8 |
The major general conclusion from this table is that all four plant proteins – even when their production yields comparatively higher emissions than more efficient methods of producing them – are generally associated with fewer carbon emissions than animal proteins produced by the lowest-emitting (most efficient) method. This is true all over the world considering all food production systems.
Based on this conclusion, we see that even “sustainable” meat (produced with the fewest carbon emissions) is not as carbon-friendly as even the least efficiently produced plant proteins in every case except two (chicken vs. nuts or tofu). “Sustainable” meat is certainly never carbon-friendlier than the most efficiently produced plant proteins.
We also learn from this table that:
- In the case of high efficiency production (second column), dairy cheese has a higher carbon footprint than chicken and the same as pork.
- The trees nuts grow on often absorb more carbon emissions than nut production creates, resulting in nuts’ negative carbon footprint.
