Carbon Footprint: The Food We Eat

You’ve probably seen this statement if you read sustainability news: going fully vegan could reduce the carbon footprint associated with the food you consume by up to 73%. However, many sources misquote this statistic, and state that going vegan could reduce your overall carbon footprint by up to 70 or 80%. This is not true. The carbon footprint associated with the food we eat makes up only 15-17% of the average carbon footprint of a household. So, if you reduce your food carbon footprint by 73%, you will impact your total carbon footprint by 10-12%. As well, it is worth noting this is based on a small number of research papers, and requires further scientific validation. However, it is the best measure we have at this time.

In short, don’t stress if you cannot face the possibility of going vegan, or if a vegan diet is not the healthiest choice for you. There are lots of ways you can reduce your carbon footprint by 10-12%. These numbers are simply useful in helping us to understand the scale of impact we can have by changing the way we eat. They are certainly not meant to be proscriptive, and I am skeptical of those who use them in that way.

The carbon footprint linked to the food you eat has many elements. The type of food, the method of production, and the distance between food production and food consumption are all things that can impact the carbon footprint associated with the food you consume. By regularly choosing foods that have a lower carbon footprint, you can have a measurable impact. Let’s keep it in perspective, though. The changes you make are not likely to reduce your overall carbon footprint by more than 10%.

Food Production

The Environmental Working Group has put together a handy chart that shows you how different foods stack up against each other with regard to the carbon footprint associated with their production. Carbon emissions are highest amongst ruminant animals: beef and lamb, for example. Cattle beef by far has the highest estimated emissions associated with its production. Ruminant animals emit methane when they burp and toot, significantly increasing the emissions they produce in a lifetime. Methane has a warming capacity 80 times greater than CO2 in the 20 years after it enters the environment. However, methane does not stay in the environment as long as CO2, so there is the opportunity to have a greater impact in the “short”-term by reducing methane emissions. As well, there is encouraging research regarding the impact of adding seaweed to cattle feed, which holds the potential to reduce methane emissions in future (research on this is emerging). Chicken and responsibly farmed fish, on the other hand, emit one-tenth of the emissions associated with cattle beef, on average.

When looking at these figures, however, it is very important that we keep in mind that they are global averages, which mask huge variability across the regions. For example, beef production is the worst offender in the EWG chart, with an estimated 50 kilogram Carbon Dioxide Equivalent (kgCO2e) globally per 100g of protein. However, in the UK, beef production has much lower emissions associated with it, as compared to the global average. Beef production in the UK has a kilogram Carbon Dioxide Equivalent (kgCO2e) per 100g of protein of between 6.53 and 8, depending on the method of farming. The lowest emissions are associated with organic farming methods. The next lowest is grass fed beef, and the highest are associated with more intensive, feedlot farming practices. The global figure cited by the EWG above is 7.6 times higher than this, at 50 kgCO2e. We find similar results across the EU and USA, where CO2e associated with beef production are in the same average range as the UK.

Oklahoma State University has put together a lovely graphic that demonstrates the relative emissions of beef production globally. There is good reason to conclude that, yes, reducing red meat consumption will reduce emissions. However, much more achievable and equally important for Western European and North American omnivores is to consume locally and responsibly produced beef over imports. The emissions associated with beef produced in the EU, US and Canada are up to 80% lower than the global average.

There are some really positive and exciting stories coming from farms focused on regenerative and circular farming methods. For example, White Oak Pastures in my home state of Georgia, USA, has achieved carbon positive beef production. They estimate carbon sequestration of 3.5 pounds per pound of beef produced.

Food Transport

Other emissions associated the food supply chain that get a lot of focus are the transport miles between the farm and your local distribution center (as in, how far did your vegetables travel to get to the shop), and the miles between your house and the shop or distribution center. You can reduce the carbon footprint associated with your weekly shop by choosing produce that was grown closer to home. However, you can see from this World in Data chart that compared to food production itself, the carbon footprint associated with food transport is relatively small. Consuming food grown closer to home does offer greater transparency into the method of production, however, and could have a double benefit of lower emissions associated with transport and lower emissions associated with sustainable, less intensive production. (I say could because this has not been repeatedly proven in all regions or contexts; it would be highly dependent on a number of external factors.)

So, if you are deciding between beef farmed down the road or beans grown half-way around the world, the emissions associated with the beans will still be lower. That is not to say that beans grown half way around the world are always the appropriate choice – as certainly there are other factors to consider. It is safe to say, however, that locally grown beans have a much lower carbon footprint than ruminant animals, particularly those farmed irresponsibly. Therefore, swapping a beef stew for a bean stew every once in a while does make a difference in emissions.

Conclusions

One benefit of eating less meat is that it frees up more budget for higher quality food items that are farmed less intensively, which can also have a positive impact on emissions. Intensive farming refers to farming practices that rely on large amounts of capital and labor inputs in order to maximize agricultural outputs across a land area. Organic farming relies primarily on natural methods of pest control and does not allow the use of chemical pesticides. The research on the emissions impact of farming method is mixed and emerging. While organic and regenerative farming methods are showing great results, they cannot keep up with the productivity rates of intensive farming overall, meaning more inputs to produce the same weight of output. Put plainly, organic and regenerative farms have less emissions per acre, but industrial farming produces way more meat per acre, and therefore looks better when the numbers are reduced down to per kilogram equivalents.

According to the research available, it is reasonable to conclude that an individual farm could reduce its emissions by switching to organic farming methods. Organic farming requires fewer chemical inputs and fertilizers, all of which have emissions associated with them. Studies looking at less intensive farming practice, coupled with organic methods do show significant reductions in emissions. However, they also show much lower crop and livestock yields which have to be made up elsewhere.

So, the scientific community cannot say, with confidence, that local switching to organic farming will result in global GHG emission reductions. You see, in order to maintain consumption levels, it is assumed we would start importing more food to make up for the shortfall in domestic production caused by switching to less intensive organic farming methods. That imported food has higher emissions associated with it. So, when you consider a switch to organic farming in a global context in which consumption patterns remain the same, the results are mixed.

Overall, this is a complex topic with a small but growing body of research supporting it. There are a few things that we, as individuals, can take away from the existing evidence. Firstly, if you can reduce your meat consumption, and consume organic or sustainably farmed livestock instead of intensively farmed livestock, that will have a small impact on your overall carbon footprint. If you can source as much of your food supply as possible from local, sustainable farms, that will reduce the emissions associated with the food you eat. However, the scale of that impact as it relates to your household’s overall carbon footprint is relatively minor. But, lots of people making a relatively minor impact translates into a major impact. So, take what steps you can and don’t feel guilty about the steps you can’t.