The carbon foodprint of 5 diets compared

by Lindsay Wilson in Food

Comparing Carbon Foodprints

It is well understood that meat production has a big carbon footprint.

Numerous studies detail the climate impact of livestock, but just how big is it’s impact on a person’s foodprint?

This post compares the carbon footprints of five different American diets and finds that when it comes to foodprints vegan’s lead the way.

The carbon footprint of different diets

Even since the FAO announced that 18% of global emission result from livestock people have talked about the climate benefits of reducing meat consumption.

More recent studies show that food system emissions could account for as much as quarter of all human emissions.  That is 12% from agricultural production, another 9% from farming induced deforestation, and a further 3% from things like refrigeration and freight.

Such studies beg the question, what is the impact of meat on an individual’s foodprint?

This analysis tries to answer that question using data from the US.  In it we compare five different diets:

Meat Lover, Average, No Beef, Vegetarian and Vegan

For each diet we look solely at the emissions associated with food supply, so we do not include those from consumer’s transportation, storage or the cooking of food.  Nor do we consider land use change emissions.

Rather than bore you with the methodology let’s start with the results and work back through how they were calculated.

The results of our analysis look like this:

The Carbon Foodprints of Different Diets

A Vegetarian’s foodprint is about two thirds of the average American and less than half that of a meat lover.  For a Vegan it is even lower.  But perhaps most interestingly, eating chicken instead of beef cuts a quarter of emissions in one simple step.

An Average American’s diet has a foodprint of around 2.5 t CO2e per person each year.  For a Meat Lover this rises to 3.3 t CO2e,  for the No Beef diet it is 1.9 t  t CO2e, for the Vegetarian it’s 1.7 t CO2e and for the Vegan it is 1.5 t CO2e.  Each of these estimates includes emissions from food that is eaten, wasted by consumers and lost in the supply chain.

In the average diet animal products make up 60% of emissions despite accounting for just a quarter of food energy.  For the Meat Lover beef consumption causes almost half of emissions from just a tenth of food energy.  In the No Beef diet all the reductions from the Average foodprint come by switching from beef to chicken.  The difference between the Vegetarian and Vegan diets arises from dairy consumption being switched to a mix of cereals and vegetables.

Perhaps the most fascinating thing is that although the foodprints vary greatly, three fifths of each diet is identical.  In other words, 60% of food energy consumed is the same in each of these four diets.

The share that is constant accounts for 1550 kcal of food energy per day and about 0.7 t CO2e of each foodprint.  So all the variation depends on the remaining 1,000 kcal per day.  The Vegan gets these 1000 kcal for 0.8 t CO2e, the Vegetarian for 1 t,  No Beef for 1.2 t, Average for 1.8 t and the Meat Lover for 2.6 t.

The diets we compared

Each of these five diets are variations of the average American diet based on data from the USDA’s Economic Research Service.

For each of our diets we assume consumption of around  2,600 kcal of food energy each day, roughly equal to an average American.  This should not be confused with total food supply which is around 3,900 kcal each day.  In each diet food energy is split up among nine different food groups.

The five diets are all variations on the average diet.  We assume the Meat Lover eats more red meat, white meat and dairy in place of some cereals, fruit and vegetables.  The No Beef diet is just the average diet with all beef consumption switched to chicken.  The Vegetarian switches away from beef and chicken to fruit and vegetables, while also reducing oils and snacks.  The Vegan does much the same as the vegetarian while also eliminating dairy through further switching to cereals, fruits and vegetables.

In terms of food energy distribution the diets look like this:

The diets we compared

The food energy that remains the same is each diet is roughly 450 kcal of cereals, 80 kcal of fruit, 50 kcal of vegetables, 580 kcal of oils, 220 kcal of snacks and 180 kcal of drinks.

Comparing food group emissions

The reason that these five foodprints vary so much despite being so similar is that the carbon intensity of food consumption differs greatly between the food groups.

To estimate each foodprints we first calculated the carbon intensity of food consumption in each group.  This involved estimating the cradle to retail emissions of food production (kg CO2e/kg product), converting each to emissions per unit food energy produced, and then adjusting for food waste and supply chain losses.  This gives emissions per unit of food consumed (g CO2e/kcal).  For a more complete explanation see our shrink your food footprint page.

The carbon intensity of food consumption for each food group is as follows:

Comparing emissions of consumed food

These figures estimate the emissions produced in the process of supplying a kilocalorie of food energy for each food group.  They show on average how carbon intensive it is for Americans to get their energy from the different food groups.

Unsurprisingly red meat is the most carbon intensive way to get food energy, followed by dairy, fruit and chicken.  Cereals, oils and snacks are the least carbon intensive.  These factors are the reason why foodprints gets smaller as less red meat, dairy and chicken are consumed.

Although the carbon intensity of food production is the main driver in these figures, each is also influenced by how calorific foods are and what scale of supply chain losses and consumer waste they suffer.

For example oils, snacks and cereals are each highly calorific and have relatively low losses and waste, which results in them performing very well.  The opposite is true of fruits and vegetables which are less calorific per unit weight but have a very high share of consumer waste and supply chain losses.

Using food groups also hides great variation of carbon intensity within each group.  A hot housed tomato can have emissions 5 times higher than one grown in season, potatoes have tiny footprints compared to many other vegetables, and cheese has much higher emission than milk.  So by limiting ourselves to just nine food groups we greatly understate the potential that changing diet has to reduce food emissions.

What about my foodprint?

This analysis attempts to show the important role animal products, and red meat in particular, have in determining the scale of a person’s foodprint.  It’s relevance to your own foodprint will depend on what your own diet is like.

Because we use national averages for food consumption, production emissions, food energy content, food losses and food waste  our estimates may vary significantly from an individuals diet.

Such caveats aside, this analysis does highlight that a small share of the food we eat can cause the majority of our food emissions.  Beef, lamb and cheese are among the most carbon intensive things we can eat, while milk, out of season fruit and other meats can also have relatively high emissions.

Shifting some of your diet away from these foods towards cereals or in-season fruit and vegetables is a very effective way to shrink your foodprint.  If your aiming for a very low carbon diet, you won’t do much better that a seasonal vegan diet, particularly if you also limit food waste.

 

For further reading food emissions check out:

Don't forget to grab your free copy of our eBook, Emit This.

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  • Gerardo Tristan

    You should make this information into a full campaign and also an app for cell phones and other gadgets! This informations is sooooo needed!Where I can find this very same info in Spanish?

    • Lindsay Wilson

      If you can find data on the average Spanish diet you could calculate something similar. The US is an easy choice because the USDA provide a lot of data about diet. Cellphones and apps . . maybe one day ;-)

  • adam

    Does this study account for the impact of Methane and Nitrous Oxide gas releases from Animals? If not, these results are misleading and inaccurately reflect the Warming impact of a Meat vs Vegetarian diet.

    • Lindsay Wilson

      Yes it does, all figures are in CO2e, thus inclusive of NOx and CH4. Across the average US diet the emissions are reasonably well split between all three. In terms of the groups nitrous oxide and methane emissions have a much bigger role in the beef and dairy groups. I’ll add a note to make this more obvious

      • Kias Henry ?

        also what about water? surely very important as well.

        I heard recently that the dairy industry in Australia uses 35 times more water then any other industry.. it would be good if you had some info on this.

      • wideEyedPupil

        Not really it underplays methane to express it in 100 year timeframe.

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  • Lori

    It just kills me that you think vegans eat so much cereals and breads! Almost 50% of vegan diets is cereal and breads? Where are you getting these numbers from?
    I also think vegetarians (other than the ones heading towards vegan) eat more dairy as they give up meat and try to eat a lot of dairy thinking they need the protein (so so wrong!) You also have vegans and vegetarians eating less fruit than the meat eaters and average diet eaters. I think you percentages of foods eaten in most of the catagories all wrong!!

    • Lindsay Wilson

      Hi Lori, thanks for your feedback. I have some sympathy with your point about the cereals, but it is worth remembering that cereals are highly calorific, and that is why they dominate the vegan diet in terms of calories, but not mass.
      As stated the analysis also assumes all people eat the same number of calories, while it is well known that vegans eat fewer in general. Lastly, I think you misread the legend for fruit and veg, as in these diets both vegans and vegetarians eat more than double the fruit and vegetables of the normal diet. You can run your own numbers using our carbon calculator. Best, Lindsay

      • Alexandra Belzon

        Quite interestingly, my boyfriend (who is vegan) only eats bread on occasion as he finds it boring. He eats cereals from time to time but mostly he eats fake meat. He really dislikes fruit and does eat quite some veggies at dinner, but it’s mostly food based around fake meat. Is that considered in the study? I don’t know in which category that falls O:

        • http://www.EcoReality.org/ Jan Steinman

          Interesting… I think vegans who “mostly eat fake meat” are perhaps much higher up the impact scale than this study would indicate.

          It really bothers me that most products targeted to vegetarian/vegan diets are heavily processed and heavily packaged.

          A vegan who cooks all their food from basic ingredients has my undying respect. One who subsists from “fake meat” is only smugly fooling themselves about their impact.

          • Alexandra Belzon

            Nah he doesn’t imply that his carbon footprint is small, he just doesn’t want animals to suffer.
            I guess that’s it. But yeah I wonder about their carbon footprint.
            Maybe the author knows.

          • http://www.EcoReality.org/ Jan Steinman

            “he just doesn’t want animals to suffer…”

            … at least directly.

            Mechanized industrial agriculture causes a lot of animals to suffer. I’ve seen a flock of vultures following a combine around the field, gobbling up the many small rodents and snakes killed.

            To be true to his desires, he needs to grow his own food, and get off the fake meat fake “no animal suffering” kick.

          • Alexandra Belzon

            Well in an ideal world all humans should kill themselves.

          • http://www.EcoReality.org/ Jan Steinman

            “in an ideal world all humans should kill themselves.”

            With climate change, peak oil, burgeoning population, nuclear melt-downs, disappearing topsoil, and looming financial collapse, we appear to be working steadfastly toward that goal!

  • Fireweed

    Nice work, Lindsay! I’ve been unsuccessful in finding you on FB. I thought you might be interested in the following page: The Elephant in the Room is a COW. I hope you will drop by for a visit! https://www.facebook.com/groups/515390858491078/

    • Lindsay Wilson

      Thanks Fireweed, I had a quick look. Really gald that you clicked through to the CGIAR Big Facts page, as I think it is one of the best resources on the web for agricultural emissions, Lindsay

  • Boris

    According to your calculator a raw vegan’s foodprint is around 3.5! You must be joking.

    • Lindsay Wilson

      Well, I must say I’d love to see the numbers you entered to get that figure. Although it could be possible, I very much doubt it. The problem is likely to come from the carbon intensity.

      In the calculator the carbon intensity of vegetables per unit energy is based on the US average, which while lower than red and white meats is much higher than grains, sugars or oils due to their lower energy content as well as the considerable spoilage of them that occurs.

      In the case of a raw vegan it is likely they eat many more legumes and starchy vegetables than the typical American, which means you would need to reduce the carbon intensity of the vegetables group considerably as these are very low carbon compared to things like salad vegetables.

      Although it isn’t in the food section of the calculator a raw vegan must save considerable cooking energy too.

      Regards, Lindsay

      • Boris

        Well actually my main source of calories comes from fruits. Around 2000 and around 200 from vegetables. The remaining 200 calories are nuts and seeds.

        • Lindsay Wilson

          2000 calories of fruit! That is pretty impressive. If you eat a lot of bananas, apples, oranges or melons you should dial the intensity right down. Avocados, strawberries, raspberries on the other hand can be very high, as can exotic and perishable fruits which are flown in. Hopefully one day I’ll make it more granular than food groups.

          • Boris

            Lots of bananas, oranges and apples yes and some dates. Strawberries, raspberries, blueberries, apples, pears, tomatoes and most of the vegetables come from our own garden. Thank you for the quick response, I feel relieved now :)

          • Lindsay Wilson

            The scary thing is that in the US only half of fruit produced is actually consumed, which is half the reason the intensity is so high. 27% of total production is ‘lost’ before being sold due mostly to spoilage or poor aesthetics, while 23% is wasted by consumers. http://shrinkthatfootprint.com/shrink-your-food-footprint

            On the grow you own front if you avoid artificial light and heat, go easy on synthetic fertilizer and make your own compost that food can be incredibly low carbon, not to mention delicious. We grow salads, herbs, tomatoes, peppers, zucchini, eggplant, beans, strawberries, broccoli, carrots and blackberries. Really wish we had more space for apples, pears, raspberries and corn.

          • Boris

            Agree. We do make our own compost. I’m from Europe.

          • Lindsay Wilson

            Well there you go. You should dial everything down then as production, losses and waste each tend to have lower footprints here with the exception of hot housed vegetables and air-freighted fruit

          • http://www.EcoReality.org/ Jan Steinman

            “in the US only half of fruit produced is actually consumed”

            This is where Permaculture strategies would improve things!

            We waste nothing!

            So many of the calculations are based on open-ended systems — the feed that goes in has a carbon cost, the poop that comes out has a carbon cost, etc.

            What we need are models for looking at closed systems. Then I think you’d see the carbon cost of many so-called “carbon-intensive foods” drop like a rock.

            The problem is not what we eat. The problem is how what we eat is produced!

            Back to your assertion about fruit: we pick tens of kilograms of wild blackberries each year. We steam-juice them, resulting in a room-temperature-stable feedstock for jelly making. We strain the resulting pulp and freeze it, for subsequent use in baking. Then we feed the seedcake to our goats, who turn it into milk! (And they also turn it into “brown gold” plant food, which we pile up with water-filled tubing that heats part of our greenhouse.)

          • wideEyedPupil

            No it’s what we eat too. In Australia 55% of emissions come from the land use sector and the vast majority of that is from livestock industries, even if you could convert that to permaculture (your ‘how we eat’ but it’s not possible in Australia’s vast semi-arid regions anyhow) there would still be massive emissions from enteric fermentation even if savannah burning and deforestation were stopped like they should be.

            BZE and MSSI in Australia will be releasing data on this already presented at the Tyndall Radical Emissions Reductions conference (December 2013) in a couple of months, watch this space…

          • http://www.EcoReality.org/wiki/User:Jan_Steinman Jan Steinman

            I’m not feeling heard.

            I said we should be looking at ways of improving the carbon footprint of many things that we already eat, and WidEyedPupil came back with statistics on the current way of doing things, while asserting that Permaculture, which was invented in Australia, was somehow unsuited for Australia!

            Since we seem to be talking right past each other, I think I’ll bow out of this conversation now.

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  • Space

    Very nice, although I can’t find stats for legumes, seeds and nuts…

    • Lindsay Wilson

      Annoying no simple answer. The data is USDA. In general seeds are part of fruit, legumes in veg and nuts in fruit or snacks (peanuts). I will break them out in to individual food eventually

  • maxemoose36

    Thanks for writing this article.

    I’ve had numerous people belittle my decision to go mostly (but not strictly) vegetarian/vegan because they point out cheese comes from cows…of course they themselves aren’t doing anything to help the environment; they’re just looking to criticize.

    Glad I can point to this now.

    Thanks again!

    • Lindsay Wilson

      While it is theoretically possible for beef and dairy to be close to carbon neutral (through soil carbon sequestration) the current reality is livestock causes about a tenth of global emissions, and this is growing sharply. This link is excellent for more info: http://ccafs.cgiar.org/bigfacts/livestock-emissions/

      • wideEyedPupil

        My hunch is that is under playing it a lot. New research to be released in Australia by MSSI will demonstrate agriculture in Australia accounts for 55% of national emissions using 20 yr timescale and latest IPCC AR 5 (2013) GHG values and of that it’s almost entirely from the livestock industry due to enteric fermentation and land use patterns. One of the most extensive land use patterns is burning of savanna in northern Australia from regrowth of open forest and woody weed vegetation to promote shirt term grassland. In the USA one must consider the deforestation of Sth Amercia rainforests at a frightening pass to grow feed crops (typically soy).

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  • CleanOttawa

    How does this study not include eggs for vegetarians? Surely factory farming chickens for their eggs creates a footprint.

    • Lindsay Wilson

      The food groups are defined by the USDA data

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  • whitenoise23

    Does this study account for the difference in carbon footprint for raising meat in factory farms vs. small scale organic agriculture?

    • Lindsay Wilson

      No it doesn’t. It is based on the national averages. Most studies don’t show a lot of difference between organic and normal production for emissions. The thing that can make a big difference is how extensive the farming is. If carefully managed on large areas of grass cattle can help to sequester soil carbon thus reducing their net emissions, but it is very hard to get right and rarely happening on commercial scale.

      • peterspendelow

        Hi Lindsay – A lot of people get it wrong about grass-fed beef and global warming. The great work by Nathan Pelletier and others (http://www.leopold.iastate.edu/sites/default/files/pubs-and-papers/2010-04-comparative-life-cycle-environmental-impacts-three-beef-production-strategies-upper-midwestern-unite.pdf) demonstrates that pasturing animals unfortunately produces much more methane (from digesting the cellulose in grass) and also takes longer for the animals to reach market weight, meaning that they are producing greenhouse gases for a much longer time per pound of meat. The arguments that pasturing animals sequesters more carbon are weak. Usually they try to compare pasture to degraded farmland. In fact though, many animals are grazed on land that once was forest, and that would grow back to being forest again, sequestering much more carbon dioxide, if they were not continually maintained as pasture. The methane impacts on their own are pretty substantial.

      • http://www.EcoReality.org/ Jan Steinman

        “Most studies don’t show a lot of difference between organic and normal production for emissions.”

        I’d invite you to challenge that!

        Specifically, the Rodale Institute has done some excellent work, showing that small-scale, organic agriculture has a significant reduction in carbon output.

        Also, look at the work Alan Savory has done. In short, he claims that we must manage cattle the way that wolves managed bison, and a net carbon sink will result.

        I think we operate our Permaculture farm as a net carbon sink, but all the models I look at have many mainstream assumptions, such as how much carbon your home costs, based solely upon its size. (We close off unused rooms and only heat the core, from locally-collected dead wood, incorporating the ash and biochar into our growing media — net-zero carbon, as far as I can determine.)

        In other words, what people are seeking is guidance, not judgement. “How can I keep eating meat and still improve?” rather than “You must stop eating meat, or the Earth is doomed!”

        I am a vegetarian, but I believe that is a luxury, supported by the industrial food system. Goats and cattle can forage on land not useable for agriculture, but that is rarely included in studies.

  • Neil Fedder

    who the hell pays for these useless studies. and just wanted to say just grabbed a nice juicy striploin out of the fridge for dinner tonight

    • Lindsay Wilson

      Nobody pays for them. That’s why they are useful

      • Neil Fedder

        excuse me but do you live in such a delusional world that you believe that this study was done for free, must be nice in your world where everything is free. Did you even bother to check the sources for this study. Believe me these companies do not work for free.

        • Lindsay Wilson

          I’m the author. And while appreciate nothing is done for free, not all rewards are economic

        • Mark Stentson

          lolololololololol you’re so idiotic it’s painful, neil.

          • Neil Fedder

            wow the best you can come up with is that. Whats painful is reading comments written by moronic imbeciles such as yourself. When I read the kind of tripe that you write I wonder to myself “That’s the sperm that won!”

    • Melody

      Ooh, you don’t care about animalas or the environment, you’re so edgy!

  • D fong

    Hi, the info is helpful. Please advise the date of your article, Lindsay. Also, there was a study / publication in 2009 showing that animal agriculture could account for up to 51% of all GHG emissions worldwide. The significant jump apparently was due to the CO2 that all animals had to breathe out. This wouldn’t change the picture and conclusion of your article. But I wonder whether or not the 25% carbon-equivalent GHG emissions cited in your article was underestimated. Any comments please? Thx.

  • idamae

    I don’t eat red meat or pork, and haven’t since march of this year, and I can’t lie, when I read this I did feel a little good about myself, considering the fact that the reason I cut it out was for the animals and the carbon emission issue… it’s really cool to see it set up this way

    • Lindsay Wilson

      Curiously enough the biggest benefit you’ll see yourself will know doubt be health

    • http://supercarrot.com/ supercarrot

      i don’t want to be a killjoy, but it takes a whole lot more individual chickens/turkeys to produce the same amount of meat that one cow would have. (so if you’re going to choose between eating large animals vs small animals, you need to make a decision of whether you care more about reducing lives lost or reducing your carbon footprint.)

      • Lori Wheeler

        Or make the decision to do both and go 100% plant based vegan :)

        • http://supercarrot.com/ supercarrot

          well, yeah, but i didn’t think i had to state the obvious. :-)
          (some people have to take baby steps. and that’s okay)

          • Lindsay Wilson

            I don’t think that is a killjoy point at all, but then climate is already quite depressing. And surely there are more ethical vegans than environmental ones, reinforcing your point. The stuff I’ve seen about battery farming certainly affected me.

          • http://supercarrot.com/ supercarrot

            i was just referring to idamae’s comment that she was feeling good about herself because she cut out eating large animals “for the animals” but the chart above shows that small animal consumption is increased when people cut out large animals. (therefore a total killjoy point when you stop to think about it.)

            it’s entirely possible she replaced her red meat consumption with produce (in that case, not killjoy! yay!) but if she replaced it with small animals, then :-(

          • Lindsay Wilson

            Oh yes, I’ve followed back up the thread. Nonetheless you make a solid point. If you are just looking for protein the mycoprotein comes in a bit better than chicken. Without the awful conditions. Seasonal vegan with lots of tree fruit still trumps all

          • http://supercarrot.com/ supercarrot

            don’t forget the beans! (especially lentils) and quinoa too. mmm.

          • Lindsay Wilson

            I do love my pulses, but quinoa? I keep on trying but it never floats my boat

          • http://supercarrot.com/ supercarrot

            are you rinsing it thoroughly? (i avoided it for nearly a decade because my first experience was unrinsed. so so bad! talk about soapy!)

          • idamae

            I actually have been slowly eating less meat since I cut out red meat. I used to be a big meat eater but not so much now. So I guess it all depends on the person.

      • idamae

        No I get it…. I mean its really not making a big difference, but I’m really trying to go vegetarian and I’m just trying to make steps in the right direction…. it really would be amazing to go vegan, but I don’t think that will be for a long time for me…. and thank you for that comment… I didnt know that about chickens

        • D fong

          Hi Idamae, it is easier than you think to go vegan. Please check out http://www.pcrm.org and sign up for the 21-day vegan kickstart. Even if you don’t want to go vegan right away, you can get an idea as to what to eat and how to put food items together. PCRM (Physicians Committee for Responsible Medicine) was formed by a group of medical doctors 30 years ago and is doing many wonderful things. They recently won a debate on the topic ‘Don’t eat anything with a face’. Cheers, Debbie

          • idamae

            Thank you! I will definitely look into it :)

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  • Xana Villa

    Very cool way of presenting data, I like your shrinking pie charts at the beginning. Also, very well explained within the text. I notice you cite several sources for your emission factors (LCA, I/O, etc…), did you have to calculate your own or did you use already published data?

    • Lindsay Wilson

      The calculations are my own, but the underlying data comes from a bunch of sources as shown. I used a hybrid bottom up and top down approach, then double checked it against a few existing studies.

      • Xana Villa

        thanks for your quick reply. I was just wondering if I had missed the publishing of new data. So, did you make average product groups (e.g. dairy) to determine the calories per kg and the emission per kilogram, or are these groups the ones you say are defined by the USDA? If so, are they available anywhere?

        • Lindsay Wilson

          Had to start with defined food groups from ERS/USDA (http://www.ers.usda.gov/) for the food availability (you can get this calories too), then use every IOLCA/LCA bit of data I could get to work out weighted averages for the intensities. This is easier for more homogenous groups like cereals, harder for something like fruit.

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  • Katie Hart

    im not any of those lol i’d be the “average” one but i eat more vegies, fruit, and a hell of a lot more drinks than meat xD

  • Andrea

    Wow, I am amazed at the ability of people to focus on the negative in an obviously important thought experiment, whether or not there may be a few limitations to the study. This is why the earth is doomed, because of people who would rather criticize and nitpick a meaningful investigation than admit or care that making a few simple changes in their lives could make a difference to the planet. Thank you for this!

    • Lindsay Wilson

      Thanks Andrea. The study obviously has some limitations, but I’m pretty upfront and transparent about them. I think its popularity show’s many people find it useful.

    • jude arsenault

      it’s because most people are selfish and stupid

  • http://www.EcoReality.org/ Jan Steinman

    You note the 5:1 difference between a hot-house tomato and a field-grown one, and yet there is surely a similar range of “error bars” for dairy and eggs, no?

    It would be good to see what options people have in each diet type. It may be easier to get people to eat free-range beef (for example) then to have them give up beef completely. Similarly, I am certain our free-range goats and chickens, incorporated in a Permaculture system that feeds them from poor land and returns their nutrients to food production, have a negligible carbon footprint.

    A similar argument can be made about heavily-processed vegan food. I’ll bet my Permaculture-based raw goat dairy products are way lower in impact than tetrapacked soy milk! And I don’t have to take heavily-packaged B12 supplements, either.

    Overall, this view of things seems divisive. It would be nice to see a comparison based on food sources, rather than types. Does a zero-carbon subsistance-farmed omnivore really have more impact than a industrially-supported vegan?

    • Lori Wheeler

      If everyone ate free range beef our planet could not sustain that as there wouldn’t be enough grassland with the large population. We also wouldn’t have enough fresh water for all this cattle. But getting rid of factory farming is a must, and if more went vegan then yes the rest could eat free range beef!
      I would like to see dairy eliminated all together as it is not needed for human health and is such a cruel industry. This would be a huge positive for our planet :)

      • http://www.EcoReality.org/ Jan Steinman

        You need to come see our raw goat dairy operation, Lori. :-)

        Also, check out the work that Allan Savory has done.

        He has an enticing, logical argument: humans have killed off the megafauna, and we need to re-synthesize that entire system through biomimicry.

        We can’t bring back millions of bison, roaming the Great Plains, kept moving by sabre-toothed cats. But we can mimic that via fast-rotational grazing on marginal lands, which ends up sequestering carbon, rather than releasing it.

        The vegan argument seems to come down to ruminants using too much land — land that could better be used by growing grain for people.

        The Permaculture argument is that ruminants are efficient gatherers of basic productivity — you can’t harvest a field with mechanized agriculture as efficiently as you can employ ruminants to do so! And especially if you manage their by-products as a resource, rather than a waste product, it’s a win-win.

        I admit that few are doing this. I wish it could get more attention. Lindsay seems skeptical.

        • Lori Wheeler

          But goats are mammals just like us and they too produce milk for one reason and that is to feed their babies. Having goats graze in fields is fantastic but let them lactate naturally when their are caring for their babies.
          No species needs another species milk. I guess this had now gone off topic from the environment to health and ethics. lol

          • http://www.EcoReality.org/ Jan Steinman

            Sorry, Lori — we must agree to disagree.

            I reject “for one reason” arguments.

            Iron ore is on earth “for one reason,” to be buried in the ground and to hold oxygen — so no one should ever use any metal artifacts. Fossil sunlight was put in the ground “for one reason,” to keep the Earth from getting too hot, so no one should ever use any petroleum energy.

            No species “needs” anything in particular from another species. We weigh advantages and disadvantages and make choices.

            I’m convinced my raw goat milk trumps tetra-pack soy milk on so many levels — carbon, nutrition, kindness to animals, etc. (Have you ever seen the vultures following a soy combine as they gobble up the snakes and rodents maimed by the machery?)

            Perhaps you don’t consume tetra-pack soy milk. Regardless, please try to understand my point that what you eat is less important than how it is produced.

          • Lindsay Wilson

            My own blog and I’m missing all the banter ;-) Jan + Lori, thanks for all the interesting points, I’ve added my take above as I needed a little width

        • D fong

          Hi Jan, quite a number of scientists have produced facts debunking Savory’s claim. You may want to check out at least Dr. Richard Oppenlander’s website. Oppenlander also made an excellent speech, available on YouTube. Let me know please if you can’t find the link(s). Cheers.

          • http://www.EcoReality.org/ Jan Steinman

            “Debunk” is a pretty strong word for what many consider a matter of scientific debate.

            One doesn’t win the Buckminster Fuller Prize by being a crackpot. A number of studies have shown merit in his contention that biomimicry can re-establish grassland that has been driven by human (mis)management into near desert.

            Yes, let’s have debate! But this is not on the lines of AGW deniers; there is hardly a consensus of criticism of Savory’s Holistic Management system.

            Personally, I don’t want to be seen as unconditionally defending Savory. But what he espouses is strongly rooted in Permaculture Principles, and it deserves study, rather than dismissal.

            I’d rather the bison and wolves be brought back. But lacking that, and given the mess that human (mis)management has given us, I think Savory’s methods deserve a cautiously applied chance — better than laying waste to millions of acres with RoundUp every year.

  • Lindsay Wilson

    Jan + Lori, here’s my take on it, purely in terms of emissions, leaving ethics to the side (even-though I think they are important too).

    I genuinely wish the message I could give for animal products was ‘what you eat is less important than how it is produced’, because I think that is a much better sell. And given the continuing rise in global animal product consumption this would seem a more pragmatic way to tackle the issue. Sadly, the data does not support this view. And climate is about emissions, not opinion. And everything on my site is about helping people with data driven information.

    Firstly, at a micro level it is true their is huge variation in the emissions intensities of different systems. However, this variation does not always reflect kindly on free-range or organic systems, unless they do a very good job of soil carbon sequestration.

    For ruminant animals feed efficiency is a key driver of emissions intensity. That is why numerous studies show free roaming pasture fed beef as having higher emissions. These animals grow far more slowly, hence emitting much more methane per unit of weight.

    Some example are linked below:

    http://www.leopold.iastate.edu/sites/default/files/pubs-and-papers/2010-04-comparative-life-cycle-environmental-impacts-three-beef-production-strategies-upper-midwestern-unite.pdf

    http://www.pnas.org/content/early/2013/12/12/1308149110.full.pdf

    For grass fed beef to be of lower carbon intensity these greater methane emission must be exceed by the carbon sequestration resulting from their grazing. This is possible, and is an area of ongoing research. But this is not happening on a wide scale currently, and is far beyond the control of consumers. The study below gives a good example:

    https://s3.amazonaws.com/s3.documentcloud.org/documents/838344/whatsyourbeef.pdf

    If you are interested in a really comprehensive systemic look at improving livestock emissions at a global scale I recommend the recent UN document. It looks at feed quality, feed balancing, manure management . .

    http://www.fao.org/docrep/018/i3437e/i3437e.pdf

    Finally, as much as I would love to believe Allen Savory’s caim that we can use animals to tackle climate change, their is very little data to support this idea. Sure, better practices can reduce livestock emissions, but this won’t put a dent in the global carbon budget. Real climate had a lucid take on the reality of the data:

    http://www.realclimate.org/index.php/archives/2013/11/cows-carbon-and-the-anthropocene-commentary-on-savory-ted-video/

    Jan, I would very much like to see the goats. From all these studies you can see that generalizations about global systems may be far from the reality in a local system. For example you system may have great carbon lock in, non-till etc

    However, given the average carbon intensities of protein production globally from beef and lamb is 58-1000kg CO2e/kg, from milk is 12-140 kg CO2e/kg, from pork is 24 kg CO2e/kg and from chicken and eggs is 4 kg CO2e/kg, I can say very safely that the easiest way for a normal consumer to cut their foodprint is to eat fewer high carbon animal proteins, and more low carbon alternatives.

    Each of the following foods comes in under 1 kg CO2e/kg: almonds, apples, apricots, avocados, beans, cabbages, carrots, cherries, chestnuts, chickpeas, currants, dates, lemons, lentils, maize, millet, oats, oranges, peaches, pears, peas, plums, potatoes, raspberries, sugar, wheat

    Based on the data, and how most people buy their food, it is much easier for a normal person to look at what they eat

    • http://www.EcoReality.org/ Jan Steinman

      “… the easiest way for a normal consumer to cut their foodprint… how most people buy their food… much easier for a normal person…”

      I guess I’m more ambitious than you. I think we need to change “normal consumers” and “most people” and the “normal person” into a very different way of doing things, rather than suggesting they merely eat different things. The new “normal” will be that nothing is normal any more!

      As ecosystems degrade and fossil sunlight goes into decline, “most people” are going to be much more intimately involved with their food. I’d rather see this happen sooner, rather than when there’s no other choice.

      Since the fall of the Soviet Union, most Russians supply a great deal of their own food. So-called “dacha gardens” supply over a third of Russia’s nutritional needs on 10% of its arable soil, versus the large, collective farms supplying only about 20% of nutritional needs, using 80% of arable land.

      Coming soon to a large, formerly-industrial nation near you!

      • Lindsay Wilson

        My ambition is to help people cut carbon, I’d like to engage as many people as possible in that idea. The use of the word normal was also in response to your suggestion people don’t want to be lectured at.

        I’ve just listed a long group of resources that show that changing how we produce animal products can only marginally reduce their emissions. In contrast, swapping those products for some plant proteins provides enormous carbon reduction.

        I very much enjoy growing my own food, using my own compost. I’d love to see a revolution on that front.

        It doesn’t change what the data says

        • http://www.EcoReality.org/ Jan Steinman

          I don’t have a lot of time to play “dueling URLs,” right now, and I will try to look over the links you’ve provided — suffice to say, there seems to be a lot of variance — the data I have seen draws very different conclusions from the data you assert.

          I’d invite you to look at, in particular, the work of the Rodale Institute, which seems to contradict your assertions regarding the potential for reducing impact by how we produce all kinds of food, including animal products.

          Without having read your links yet, I’m not casting aspersions, but the vast majority of agricultural “data” out there does not come from independent sources any more. Data deprecating organic methods generally is funded by agribusiness — often “laundered” as a grant to a University. As Upton Sinclair put it, “It is difficult to get a man to understand something when his salary depends on his not understanding it.” (Sinclair was not at all a fan of the meat packing industry! But the knife cuts both directions.)

          You might also want to check in with the Union of Concerned Scientists, who have been very active in “outing” funding sources for so-called “scientific studies” that support status-quo data.

          In short, there is a growing movement afoot to change the way we do things in order to affect change. I’m convinced this is the key.

          • Lindsay Wilson

            I’ve also got little interest in dueling URLs. I’ve read at least 100 studies on food emissions. I know all the UCSUSA stuff, I’ll check out the Rodale stuff tomorrow. Some the UN work is superb

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  • wideEyedPupil

    This series of calculations drastically under estimates meat based diets footprint. When I get a chance I’ll post some reliable data to refute it but for starters you very much need to look at land use patterns and emissions associated with it. You also need to do accounting for 20yr time frame not 100yr because it downplays the roll of methane from entropic fermentation greatly. 20yr timeframe is significant given climatic tipping points of methane and COx burps in frozen sea beds/ice in polar regions which are devastating positive feedbacks which cannot be reliably predicted but remain a clear and present danger given the trajectory we are on with polar ice melt (consultant my outstripping IPCC’s most radical prediction sets)

    • Lindsay Wilson

      This data is accurate for its scope, but yes it does fail to address the land use issue. This is common to all lifecycle approaches on food. Because the majority of food land use emissions occur in Brazil and Indonesia it is hard to enter them into a lifecycle approach. Tara Garnet at the Food Climate Research Network has the most interesting take on it. I touch on it here

      http://shrinkthatfootprint.com/shrink-your-food-footprint

      As I noted in another post the 20 v 100 year time frame is less important than the next forcing effect. 90% of forcing growth through 2100 is expected to result from CO2 according to the IPCC RPCs, so we need some context when discussing methane.

      • wideEyedPupil

        More and more scientists are reconsidering the emphasis on CO2, sans methane. While it is more short-lived in the atmosphere (about 12 years) it’s potency (some papers say 105x Co2) is continually being upwardly revised. IPCC AR 5 (2013) now pegs it at 84x over twenty years and 28x over 100 years. Twenty years is significant because of climatic tipping points we may cross inside twenty years. Using 100 years is effectively averaging the damage away while it is methane and warming the atmosphere much much more than a CO2 molecule because for 90% of that 100 years it’s a CO2 molecule in the atmosphere or sequestered or absorbed by a water body.

        I don’t understand what you are saying by this:

        “less important than the next forcing effect. 90% of forcing growth through 2100 is expected to result from CO2 according to the IPCC RPCs”

        IPCC has continually missed the mark on polar warming and ice melt. In the next twenty years polar warming could hit irreversible tipping points, bringing more positive feedbacks into the system like frozen methane and CO thaw that completely dwarf our carbon budget. In fact Australian scientists are now calling it game over for a massive glacier on the Western peninsula of Antarctica even though it’s still 80% intact from fifty years ago over whenever they can get measurement data back to.

        • Lindsay Wilson

          Radiative forcing is the correct measure of what is warming the earth, that is why I refer to it rather than GWP. I would concur that the major concern with methane is the possibility of permafrost methane gushing into the atmosphere. But the major agent causing this warming is CO2, that is entirely my point

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  • Tim Small

    Nice illustration of just how many of us, and our livestock there now are:

    http://xkcd.com/1338/

  • Anne

    I have been vegan for 13 years, and for the rest of my life. It’s about giving back, and about growing and becoming a better person than you were. And along the way you help the animals, the environment and helping those who don’t have anything to eat; we could grow food to feed those who are going hungry, instead of feeding it to the animals. And the way farm animals are treated, is the most disrespectful thing I have ever seen.These poor animals are mass produced; kicked, beaten and treated in the most inhumane manner, and the conditions they’re forced to endure. You couldn’t fathom it. My boyfriend recently became a vegan after watching “Best Speech You Will Ever Hear” by: Gary Yourofsky. You will learn things that you may never have known.

  • yamanassaf

    why not reference your article properly like wikipedia references. I need to see some links.

    • Lindsay Wilson

      I try to add links where possible in the hyperlinks, but its a fair point. need to up the references on some of these more academic posts

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