Land-use Change

It's not just what you eat, but what your food eats.

Or... why animal feed needs to be a key indicator for sustainable foodservice.

Most sensible people agree that animal products have a disproportionate impact on natural resources, climate change and, in certain cases, our own health.  And whilst most metrics for understanding your impacts tend to make beef look like the bad boy of food sustainability, there is also a consensus that we need to reduce our intake of animal products in general, and eat more fruit, vegetables and healthy grains.  What is less clear is how we decide what meat/fish/dairy we should be eating, even when we are eating less (you can watch a short explanation of what "Less But Better" meat really means here).  For example greenhouse gas emissions always make beef, lamb and cheese look like a bad choice.  The same goes for land-use requirements, when "land-use" does not differentiate between cropland versus grassland and so on. 

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So this is all helpful to give us metrics to reduce our overall meat intake, but it does not help us make decisions between and within types of meat.  Is pork better than chicken?  Is this chicken better than that chicken?  Here we use data from FAO as a baseline to illustrate how knowing the type and source of animal feed can help us make informed decisions.

Impacts from different types of animal feed

Firstly, some definitions.  Here I use two key impacts:

- land-use change carbon impact, estimating the carbon emissions from deforestation etc to clear land for growing animal feed.  You could also see this as a very rough proxy for biodiversity loss, albeit with some caveats.

competitive land-use, estimating the land-use requirement to produce animal feed when that land could have been used to produce food that could be eaten directly by humans.  This matters in a world of limited agricultural land, growing populations and persistent hunger in some regions.

In this article I use three different types of feed to show the different impacts:

- soy from South America.  High land-use change impacts; high competitive land-use (assuming the land is now competing with human food since it has been changed from a natural habitat).

- grains from Europe.  Low or no land-use change impacts; high competitive land-use.

- ecological leftovers (eg grass, byproducts from agriculture that are not suitable for human consumption). Low or no land-use change; low competitive land-use.

Bear in mind that these types of feed have different feed efficiencies (ie the conversion rate of feed to meat) with ecological leftovers being generally associated with lower feed efficiency.  So the below scenarios are simply models to illustrate how we can use this as a principle to go "Beyond Carbon" in terms of indicators for more sustainable meat choices.

This chicken or that chicken?

Imagine that two staff restaurants both serve a chicken casserole for five hundred guests each, using 100g of chicken per serving.  So each kitchen buys 50kg of chicken breast.  Restaurant A uses chicken that has been fed an even split between soy from Brazil and grains from Europe.  Restaurant B uses chicken that has been fed only grains from Europe and ecological leftovers.  Based on FAO data for land-use change, crop yields and taking an average feed efficiency of 3:1 (3 kg of feed produces 1kg of meat), Restaurant A will have an additional land-use change carbon impact the same as driving over 1000km in a family car, whereas Restaurant B will arguable have no additional land-use change climate carbon impact.  For competitive land-use, Restaurant A's chicken meat would need over twice as much cropland than the chicken meat from Restaurant B.  So the chicken in Restaurant B is demonstrably a better choice.

This beef or that chicken?

The next day Restaurant A serves chicken (again... but today it's a curry), but Restaurant B serves a beef wok.  The same volumes as before, and Restaurant A uses the same chicken supplier, but Restaurant B uses beef that has been fed only ecological leftovers.  Classic LCA research shows that beef has a carbon footprint of around 25kg of greenhouse gases per kg of meat (give or take a bit), and chicken normally comes in around 5kg of greenhouse gases per kg of meat.  However, this normally assumes a low impact for land-use change carbon impact for the chicken, so in this case (based on FAO data for soy from South America) the actual carbon footprint of Restaurant A's chicken could increase to around 9kg of greenhouse gases per kg of meat.  It is still lower than the beef, but the gap has been closed a bit.  Note that we have not included the potential for carbon sequestration on the land the cattle may be grazing or indeed put a value on the carbon stock of that land if the carbon is stable, so the beef could in fact be no worse that the chicken based on carbon footprint alone.  And then let's look at competitive land-use: the beef is fed on ecological land-use so has virtually zero competitive land-use requirements, but the chicken's cropland requirement would be very significant (around 500 metres squared of cropland, loosely calculated from feed efficiency rates and FAO yield data). 

And remember this is just one day in the life of two restaurants.  Multiple that fifty times and we're still nowhere near the volume of chicken being served on a daily basis, even for a medium-sized foodservice business.  So the beef has a higher carbon footprint, but the chicken is putting more pressure on limited cropland, and in this case, deforestation.  Are we done with the "just eat less beef" thing now?

Animal feed as an indicator

These scenarios are just examples, using FAO data with a big old bundle of assumption thrown in.  It is not a peer-reviewed research paper and it of course does not mean your chicken has this impact, or your beef is not impacting competitive land-use (it almost certainly is).  But it does show how understanding what your food eats is really important for understanding the impacts of what you eat, and what decisions you can make to reduce your impacts.  Eat less meat, but eat better meat.  Animal feed is one of the factors you need to consider, and IntoFood can help you start to understand this.