Tag Archives: Carbon Footprint

Oxford Student Union’s beef and lamb ban is laughable when compared to the Uni’s air travel emissions.

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Screenshot 2020-11-24 at 12.15.33

There has been considerable publicity devoted to the announcement that the University of Oxford Student Union Council have voted to approve an on-campus beef and lamb ban, citing a desire to reduce greenhouse gas emissions.

The greenhouse gas emissions associated with beef production comprise methane, nitrous oxide and carbon dioxide, with methane accounting for ~60-80% of the total, depending on the production system. Ironically, climate researchers at the University of Oxford (who presumably don’t sit on the Student Union Council) have reported that atmospheric methane breaks down over ~20 years, unlike carbon dioxide from fossil fuel combustion (e.g. aviation fuel) which continues to accumulate over time.

I grew up in Oxford and have always loved the diversity added to the city residents by the truly global university community of students, researchers and staff.  However, it’s worth thinking about the carbon emissions of all the international flights that are therefore associated with the university (see infographic above).

To put flights into context:

  • The carbon emissions associated with a return flight to Paris = 4.8 months of beef consumption* per passenger.
  • The carbon emissions associated with a return flight to JFK = 2.8 years of beef consumption* per passenger.
  • The carbon emissions associated with a return flight to Sydney = 9.5 years of beef consumption* per passenger.

We should all take strides to reduce our greenhouse gas emissions wherever possible – surely we can only assume that banning air travel will be next on the Student Union Council agenda?

It’s worth noting that this vote doesn’t actually have any legislative power, as each college within the University runs its own catering and therefore makes independent decisions as to food sourcing. Furthermore, a vote by the Student Council is a vote by a very small proportion of students on the council, rather than the 22,000 students across the entire University. It therefore seems unlikely that the ban would be mandated without significant student revolt, but given how many kebab and burger vans line the streets of Oxford after 9pm, I imagine the proprietors are looking forwards to a huge increase in demand if it is ever enforced.

*at an average UK consumption of 18.2 kg beef per capita 

How Now, Old Cow? Do “Slaughter-Free” Dairy Farms Come at an Unsustainable Cost?

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As consumers, we’re more like sheep than we’d like to admit – that is, if sheep were tempted to buy food based on “free from” marketing. Gluten-free, fat-free, lactose-free, dairy-free and GMO-free labels are already firmly stamped on many of the foods we buy in shops and restaurants, and are associated with an invisible yet potent, virtuous halo. After all, if a slice of cake is gluten-free, it must be positively healthy.

The latest marketing wheeze appears to be “slaughter-free” dairy production – a 30 cow herd in Rutland, described as a bovine spiritual utopia, where calves are not weaned but run with cows as “grazing partners”; male calves (renamed as ”oxen”) are used for draught power rather than reared as beef; and once cows retire from milking, they are literally put out to pasture rather than being culled.

There’s no doubt that this ticks an entire list of ethical boxes – who doesn’t want to imagine that cows live a happy life browsing the buttercups once they’re too old to produce milk? Yet, given the critical need to produce food sustainably (in terms of economic viability, environmental responsibility and social acceptability), it also leads to a number of questions.

While there may well be a niche market of consumers who are prepared to pay £4.50 per litre for slaughter-free milk; in an era when we primarily choose foods based on price, is this endeavour going to achieve long-term economic sustainability?

Food purchases for EU consumers

The environmental impact of dairy production increases with the proportion of non-producing (dry cows, growing heifers or “retired” cows) in the population – keeping retired cows out on pasture would be expected to add a huge quantity of greenhouse gases to the carbon footprint per litre of milk produced. Carbon footprint and resource use per litre is also negatively correlated with milk production – the low yields associated with this type of hand-milking operation would further add to its environmental impact. How do we, as consumers, balance the relative values of animal welfare and planetary health?

FAO LCA 2

In a system where no cattle are slaughtered, but where cows need to have a calf on a regular basis to produce milk, the herd size will increase exponentially over time. In two, five or ten years time, how will the owners reconcile philosophical arguments against slaughter with the difficulty of supplying enough feed to fulfil the requirements of an ever-expanding herd using a fixed quantity of pasture?

Finally, and most importantly, animal welfare should be the cornerstone of any dairy farm. Euthanasia is upsetting, yet is the only option when animals are too sick or injured to survive. As consumers, we need to take responsibility for the fact that slaughter of both healthy animals (for meat) and sick animals (for humane reasons) is an unavoidable, if unpalatable truth. Just as the recent ban on cattle slaughter for beef in India is going to have negative impacts on food security, economic sustainability and environmental impacts, it’s time that we faced up to the reality of food production and stop thinking that we can have our slaughter-free dairy and eat it!

The Future’s Bright; The Future’s…Meaty? A Response to Breakthrough’s Essay on Meat Production

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jims-charolais-in-feedyardThis week I was asked to respond to an excellent Breakthrough article on the environmental impacts of beef production. As ever, I hope the comments below provide food for thought (pardon the pun) and I urge you to read the full Breakthrough article as well as the other comments by Jayson Lusk, Maureen Ogle and Alison van Eenennaam.

Every food has an environmental impact, whether it’s cheeseburgers or tofu, coffee or corn.

That shouldn’t come as a surprise to any of us and, as a scientist, sustainability consultant and parent, I don’t have a problem with food production being one of the biggest contributors to global environmental impacts. Why? Because food production is one of the few industries that are absolutely essential for human life. However, it’s clear that we need to take steps to reduce environmental impacts from human activity, and as such, the livestock industry is often criticised for both resource use and greenhouse gas (GHG) emissions.

Although meat production is predicted to increase from now until at least 2050, it should be noted that the trends for improved productivity and efficiency within global livestock industries also reduce environmental impacts. As described in Marian Swain’s essay on meat production, the US beef industry cut resource use and greenhouse emissions considerably between 1977 and 2007. Meanwhile, the rise of modern feedlot-finishing systems cuts land use, water use, and emissions per unit of beef compared to grass-finished meat.

These findings may seem intuitively incorrect as we’re constantly exposed to marketing and media messages suggesting that only grass-fed meats are environmentally sustainable, and that intensive livestock systems are undesirable. The data speak for themselves however—the majority of extensive systems finish cattle at lighter weights (thus requiring more total animals to maintain beef supply), have lower growth rates (so cattle take longer to grow to their finish weight) and often have lower reproductive performance in female cattle.

All these factors combine to increase environmental impacts. But when I presented this data to a group of French Masters-level Livestock Engineering students earlier this month, they were (in their own words) shocked. Even among experts and students, there remains a great deal of misunderstandings when it comes to meat production.

Does this mean that every beef producer worldwide should embrace feedlot-finishing and reduce pasture use? Absolutely not. One of the major benefits of cattle compared to swine and poultry is that they digest and use human-inedible forages, such that dairy and grass-fed beef cattle actually produce more human-edible protein in the form of milk and meat than they consume; and feedlot-finished beef cattle have a ratio of human-edible feed intake to human-edible protein output similar to that of swine, despite their greater overall land use. In keeping with the themes discussed in the Swain’s essay, there is no magic bullet—it is essential to fit production systems to the cattle, climate, market, and culture within each region and to improve productivity within each and every system.

So rather than reducing animal protein consumption as we move towards 2050, we might ponder keeping total consumption relatively stable, with a more equitable distribution across the globe? This would allow for a decrease in over-consumption in high-income regions, while providing a greater quantity of milk, meat, and eggs to those who have dire need for adequate animal proteins to maintain health and to promote adequate child growth and development. While the environmental impact of beef production is a key concern, we also have to examine the role of livestock in economic and social sustainability.  For billions of small-scale farmers, cattle provideeconomic viability, improved nutrition, social status and a means to diversify agricultural production as well as tangible benefits in terms of fertilizer, hides and other by-products.

Should we insist that global beef production is abandoned in favour of increased legumes, nuts or lab-created proteins? No. We simply need to give producers worldwide the education, tools and technologies to make the best and most efficient use of their resources. Only then will we have a truly sustainable (environmentally responsible, economically viable and socially acceptable) global meat industry.

Where’s the Beef? Not in Danish Diets.

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Culvers burgerFor those of us in the UK, mentioning Danish livestock production almost inevitably leads to thoughts of Danish bacon (be still my beating heart) – a considerable proportion of their 90% of domestic pork products that are exported. However, any beef lovers in Denmark may be in trouble, as recent news articles suggest that red meat (beginning with beef) will soon be taxed in order to cut consumption and meet greenhouse gas targets.

Despite the number of voices clamouring for reduced meat consumption, it seems clear that the average consumer isn’t going to forgo meat and dairy simply because a new study is publicised in the lay press. I’m firmly of the opinion that the only way that meat consumption will decline is if it becomes too expensive to include in the weekly shopping basket. Indeed, although meat consumption per capita has declined in the USA over the past 10 years, demand (as measured by the price that the consumer is willing to pay) has increased over recent years.

So will taxing meat lead to a reduction in consumption? For those who routinely order a 16 oz (454 g) steak in a restaurant or think nothing of tucking into a chateaubriand, probably not. High end cuts of beef are associated with celebrations and luxury dining, and going out for a broccoli pasta bake just doesn’t have that same ring to it.

However, we live in a world where 793 million people (10.7 % of the global population) are undernourished – and that isn’t simply confined to people in developing regions. That means that almost 1 in 9 people do not have enough food. To low-income consumers, food availability isn’t simply a function of what is on the shelf in the supermarket, it’s directly related to economic cost and convenience. If red meat is taxed, it will still be eaten, but there will be a disproportionate shift towards consumers with a greater income and away from those who are in most need of affordable high-quality protein, including growing children.

Do beef alternatives exist? Absolutely – protein can be supplied from other meats, fish or vegetable-based foods. Yet here’s where the convenience aspect comes in – most of us can probably think of a quick and easy recipe involving beef, but how many can you think of involving tofu or lentils? That’s not to say that we shouldn’t expand our cooking repertoires, but when time is at a premium, quick easy recipes that will feed a family win every time.

If beef becomes unaffordable, it will have to be replaced by another protein – but this substitution does not occur at zero cost. Can tofu or lentils be produced on low-quality pastureland where we can’t grow other human food or fibre crops? Do pork or poultry make such efficient use of forages, pastures and by-products from human food and fibre production that, far from competing with humans for food, the animals produce more human-edible energy or protein than they consume? No. The only livestock that do this are those pesky greenhouse gas-belching bovines.

Greenhouse gases are important, but they are not the only factor that we should consider when advocating for sustainable dietary choices. In a world where millions of people are food-insecure, removing a protein choice from the table of those with low incomes simply adds to the problem of how to feed the world – sustainably.

Seeing the Bigger Picture – Why One-Dimensional Panaceas Do Not Solve Sustainability Issues

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This week, another paper has been released claiming that we should change to a vegetarian diet in order to “…cut global food emissions by two thirds and save millions of lives“. As ever, media coverage of the paper by Springmann et al. ignored salient points regarding the importance of increasing fruit and vegetable consumption and reducing energy intake in reducing deaths from heart disease, cancer and diabetes; and simply focused on the claim that reducing meat intake would improve health and cut greenhouse gas emissions (GHGs). The simple message to the consumer? Go vegetarian.

So are GHGs the only important environmental metric? Absolutely not. What about land use? Air quality? Fossil fuel consumption? Water use? Biodiversity? The myopic focus on GHGs as the only arbiter of environmental sustainability completely ignores these factors, yet the results of the current study (and similar papers) are promoted worldwide as a panacea to solve all environmental issues.

Can you imagine a world where we only look at one consequence of our actions? Where our only consideration when buying a car is the colour of its paint? Or the criteria for accepting a new job is whether they have good coffee in the canteen? Surely a ridiculous idea – all of our actions have direct and indirect consequences, some predictable, some entirely unforeseen, and we weigh up these outcomes with every decision that we make – including dietary choice. If we examine a number of the assumptions and recommendations within the current paper, it’s apparent that the negative consequences of the one-dimensional GHG focus may outweigh any benefits gained.

Although a regional approach was used to assess population health impacts, greenhouse gas emissions in the paper were based on reference values for various foods, with the inherent presupposition that all livestock production systems are equally productive and efficient. This is a fatally-flawed assumption. If we take beef as the example: in the USA, 90% of cows have a calf every year, cows first calve at 24 months of age and growing cattle are slaughtered at 15 months of age. By contrast, in Brazil, 60% of cows have a calf every year, cows first calve at 36 months of age and growing cattle are slaughtered at 42 months of age. Both systems are suited to the resources and market available, but have wildly different efficiencies. Consumption of a US-produced steak (16.7 kg CO2/kg) will therefore have a far lesser contribution to the average person’s carbon footprint than a Brazilian steak (62.0 kg CO2/kg).

All food have an environmental impact

Replacing milk, meat and eggs with plant-based foods (legumes, nuts, etc) is entirely possible, yet it does not occur at zero environmental cost. Every single food that we consume has an environmental impact, and although the greenhouse gas emissions associated with a unit of lettuce or beans may be less than pork or beef (asparagus is a notable exception), the land required to produce equivalent energy or protein from plants is significant.

We cannot simply remove cattle from the low-quality range and pastureland that they occupy in the majority of grazing regions and assume that we can plant brussels sprouts or soybeans instead. Only a small percentage of pastureland is productive enough to produce human food or fibre crops (8.0% in the USA and 10.8% in the UK). The fact that pastureland would have to be converted to cropland, releasing sequestered carbon dioxide to the atmosphere and increasing the use of fertilisers and irrigation water, was not accounted for in Springmann et al.’s study. Indeed, from where would we source fertilisers for crop production if we significantly cut meat consumption and thus livestock populations? Is an increased reliance on dwindling reserves of inorganic N, P and K really a sustainable solution?

Finally, and most importantly, cattle do not simply exist as a source of milk or meat. In many developing countries, immense cultural significance is placed upon livestock ownership and ruminant animals play a vital role in supplying draught power, capital assets and agricultural enterprise diversification. Should a single mitigating factor for reducing GHG emissions overcome the moral obligation to support and assist subsistence farmers in developing regions? It’s vital that we take a holistic view that encompasses environmental responsibility, economic viability and social acceptability in order to improve food system sustainability rather than simply focusing on one aspect of the problem. Rather than taking a whole-system approach to environmental and human health, the study by Springmann et al. is akin to amputating both legs in order to try and cure arthritis. Short-term pain may be reduced, but long-term suffering is inevitable.

Cutting Meat? Or Just Cutting Corners?

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DexterIt is equally interesting, inevitable and lamentable to see that another study has come out claiming that the only way to reduce climate change is to cut meat consumption per person.

Meat consumption appears to be the only human activity subject to continuous “we must cease/reduce this” claims on the basis of environmental impacts. If we compare to other greenhouse gas sources, a considerable proportion come from transportation. Yet rather than insisting that every car-owner cut their annual mileage by 25%, the focus has been on reducing emissions by producing more fuel-efficient vehicles. Similarly, no one has yet claimed that we should reduce household lighting by four hours per day, but the compact fluorescent lightbulb (CFL) has become the poster child for improving household energy efficiency.

We have demonstrable proof that beef and dairy producers have improved greenhouse gas emissions (as well as land use, water use, energy efficiency, etc) over time through improved efficiency, and can continue to do so into the future. So why are the gains made by livestock producers dismissed, and reduced meat intakes seen as the only solution? I have an absolute hatred of conspiracy theories, but it is difficult not to see an latent agenda in the preponderance of “Cut meat consumption” papers. Jumping on the bandwagon? Promoting individual dietary opinions as science? Or simply bowing to NGO/media opinions and looking for easy funding and publicity?

As the global population increases to over 9.5 billion people by 2050, with the majority of this growth occurring in the developing world, the demand for milk, meat and eggs is going to increase by 60%. If we are serious about cutting greenhouse gas emissions, it’s time to examine the impacts of all of our actions and concentrate on further efficiency improvements rather than constraining dietary choice.

The Paradox of the Roasted Vegetable Sandwich – Do We Eat What We Preach?

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Large Veggie BurgerSo here’s the question: who has been out to eat with friends, family or work colleagues, ordered what’s perceived as a virtuous (low-fat, high-fibre, gluten-free or vegetarian) meal in a restaurant, and then grabbed a Snickers bar on the way home? Or, when completing a survey, stated that you are highly concerned about animal welfare or environmental issues, then gone to the grocery store and chosen food simply based on price, taste and convenience?

I’d suggest that this is a situation common to most of us – the behaviours and image that we present to the world (including our carefully-posed selfies) do not always reveal our real personality. Which brings me to the paradox of the roasted vegetable sandwich.

Yesterday, a friend complained that as a consequence of being last in the lunch line at a conference, all that was left was a “soggy veggie sandwich.” Now I attend a lot of meetings and conferences, many of which serve sandwiches, and despite being a voracious meat eater, I’ll almost always choose the vegetarian sandwich. I love egg, hummus or roasted vegetables and really hate slimy catering mayonnaise tainting the deliciousness of roast beef or ham. Luckily for me, in my experience any sandwiches left after the initial rush are inevitably vegetarian or vegan.

Obviously my view may be biased in that I attend far more meetings with a farmer or agricultural industry audience than those attended by, say, Hollywood actors or animal rights activists. But given the number of untouched meatless sandwiches, are caterers overcatering for vegetarians and vegans in an attempt to be sensitive to diverse dietary requirements; or do survey results indicating that people intend to cut meat consumption vastly overestimate the extent to which this is actually happening? Do many people who claim to be vegetarian or vegan actually eat mostly plant-based foods (Hello Beyoncé!) with the occasional hamburger?

We are inundated with messages suggesting that meat is a socially-irresponsible choice. That Meatless Mondays are wildly popular and an increasing number of people are turning to vegetarian and vegan diets to improve their health, animal welfare or environmental impact. Indeed, one UK study of the sandwiches available in grocery stores and fast food restaurants showed that less than 3% were plant-based, and suggested that this was a significant problem for the (alleged) 35% of people who are willing to cut their meat consumption. Yet if over a third of the population were really determined to cut meat intake, wouldn’t that demand have filtered back to sandwich retailers?

Despite stated consumer interest in buying earth-friendly or high-welfare products, interest seldom translates into real-life buying behaviours. Those opposed to livestock farming often state that we could feed the world (political, social and infrastructural barriers not withstanding) if we all adopted a vegetarian or vegan diet, but it seems that we simply don’t want to.

CIWF TweetCould we give up growing crops for animal feed and feed more people with tofu and Quorn? Absolutely. Yet there’s a huge gap between philosophical ideology and real world behaviour. Rather than bewailing the allegation that one-third of global grain crops are fed to livestock (ignoring the fact that a high proportion consists of human-inedible byproducts from cereal crops grown for human use), perhaps it’s time to celebrate the fact that two-thirds of global cereals are used to feed people, without being made to feel guilty for enjoying a roast beef sandwich (no mayo please).

Defending Conventional Beef in The Wall St Journal Today!

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WSJShameless self-promotion, but very excited to have an essay published in The Wall St Journal today defending conventional beef production.

Given my blog subtitle, I thought I should link to it! Would love to read your comments. Article here: http://www.wsj.com/articles/is-feedlot-beef-bad-for-the-environment-1436757037

Planes, Trains and Automobiles: Why Mass Food Transport is Eco-Friendly

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Food transportation. It’s the curse of the modern world. Just think how much brighter and sunnier the planet would be if we all shopped locally, tootling along on our bicycles to pick up freshly-baked bread and a dozen eggs just as our grandparents would have done. A brave new world unemcumbered by gas pumps and trucks. Except…. Well, no. It’s not that simple.

Food miles 2 In many cases, transport is a tiny proportion of total greenhouse gas emissions per unit of food – for example, it’s less than 1% of the carbon footprint of one lb of beef. However, food miles are often cited as an environmental proxy to differentiate between food choices, the assumption being that an egg which travels 2,000 miles across the country is less environmentally-friendly than one produced in the next county. Indeed, one farm website proclaims that “We do not ship anything anywhere. We encourage folks to find their local producers and patronise them”, while on the same page, a customer testimonial proudly proclaims: “I drive to <Farm X> 150 miles one-way in order to buy clean meat for my family”.
Food miles 4Given the dichotomy between these two statements, let’s compare buying eggs from a grocery store with a local farm (full analysis here). Food miles are far greater for eggs that have traveled from Texas to Virginia to be sold in the grocery store (2,405 miles round-trip), compared to driving to the local farm (300 miles round-trip); and the fuel efficiency is far worse for a truck (5.4 mpg) than a car (22.6 mpg); yet a modern truck can carry 23,400 dozen eggs.
Food miles 6Unless your car is packed to the roof with eggs, traveling to the farm to buy them emits 55X more greenhouse gas emissions than driving to the store to buy them. Bottom line? Unless the local farm is closer than the store, or you’re able to walk/cycle there*, it’s more environmentally-friendly to buy eggs from the store, because the greenhouse gas emissions attributable to one dozen eggs out of 23,400 dozen is a tiny fraction of the total.
One report claims that greenhouse gas emissions from one large container ship is equivalent to 50 million cars – however, in this instance it’s the result of sulphur dioxide emissions from poor quality shipping fuel rather than inefficiency. Mass transport may not have a feel-good factor associated with driving out to a farm, but it allows us to enjoy a wide variety of affordable foods with a low carbon footprint – essential factors for a sustainable food future.
*Which begs the question of how many eggs you can carry on a bicycle…

Is It Time We Stopped Shouting About The Dietary Guidelines?

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The recent report by the advisory committee to the USDA dietary guidelines has certainly caused a media stir in the past week or so. There’s a lot of nutritional common sense in the report – eat more fruit, veg, and dairy, reduce carbs and sweetened drinks/snacks, and moderate alcohol intake. Yet there’s a kicker – from both a health and a sustainability perspective, Americans should apparently be guided to consume less animal-based foods.

10982813_934682089898559_3461048965358255082_oWhen the report was released, my Twitter notifications, Facebook feed and email inbox exploded. Memes like the one to the left appeared on every (virtual) street corner, and the report was mentioned in every online newsletter, whether agricultural or mainstream media. It’s this press coverage rather than the content of the report, that really concerns me.

Individuals don’t pay a lot of attention to a government report on nutrition. Despite the fact that six updates to the guidelines have been released since their inception in 1980, we are all still eating too many Twinkies in front of the TV and super-sized takeout meals in the car, rather than chowing down on broccoli and lentil quinoa bake.

Headlines CollageYet people do pay attention to headlines like “Less meat, more veggies: big food is freaking out about the “nonsensical” new dietary guidelines” and others shown to the left. The media sub-text is that big bad food producers (so different from the lovely local farmer who sells heirloom breed poultry at $18/lb at the farmers market) are appalled by the release of this governmental bad science that’s keeping them from their quest to keep you unhealthily addicted to triple cheeseburgers washed down with a 500-calorie soda, and will do anything to suppress it.

This makes me wonder – at what point do we need quiet, stealthy change, rather than loud protests that attract the attention of people who would otherwise never have read about the guidelines? At what point does industry protesting seem like a modern version of “The lady doth protest too much“?

Rather than posting on Facebook or Twitter that the report is nonsense because the committee of nutritionists ventured into the bottomless pit that is sustainability; why don’t we instead extol the virtues of producing high-quality, nutritious, safe and affordable lean meat, and aim to reach the people who haven’t seen the hyperbolic headlines or read the guidelines simply because they’ve seen a lot of talk about them on Twitter? The old showbiz saying that there’s no such thing as bad publicity certainly applies here – the extent of the reporting on the industry backlash against the report means they have probably been noted by far more people that they otherwise might.

The impact of the dietary guidelines recommendations upon purchasing programs is far higher than on individuals, and does give rise to concern. Globally, one in seven children don’t have enough food, and school lunches are often the only guaranteed source of high-quality protein available to children in impoverished families. I may be being overly sceptical, but I suspect that if meat consumption in schools is reduced, it’s unlikely to be replaced with a visually and gastronomically-appealing, nutritionally-complete vegetarian alternative.

Sustainability doesn’t just mean carbon, indeed, environmentally it extends far further than the land, water and energy use assessed by the dietary guidelines advisory committee into far bigger questions. These include the fact that we cannot grow human food crops on all types of land; water quality vs. quantity; the need to protect wildlife biodiversity in marginal and rangeland environments; the use of animal manures vs. inorganic fertilisers; environmental costs of sourcing replacements for animal by-products in manufacturing and other industries; and many other issues. Simply stating that meat-based diet X has a higher carbon footprint or land use than plant-based diet Y is not sufficient justification for 316 million people to reduce their consumption of a specific food. Indeed, despite the conclusions of the committee, data from the US EPA attributing only 2.1% of the national carbon footprint to meat production suggests that even if everybody reduced their intake of beef, lamb and pork, it would have a negligible effect on carbon emissions.

Could we all reduce our individual environmental impact? Absolutely. Yet as stated with regards to dietary change in the advisory report, it has to be done with consideration for our individual biological, medical and cultural requirements. As humans, we have biological and medical requirements for dietary protein, and some would even argue that grilling a 16-oz ribeye is a cultural event. I have every sympathy for the USDA committee*, who were faced with a Herculean task to fulfill, but in this case, they only succeeded in cutting off one head from the multi-craniumed Hydra – and it grew another 50 in its place.

*Many people have already commented on the suitability (or not) of the committee to evaluate diet sustainability, but to give them their due, they do appear to have looked beyond greenhouse gases to land, water and energy use. They are nutrition specialists, not sustainability experts, but it would be difficult (impossible) to find a committee comprising people who were all experts in nutrition, sustainability, economics, policy, behaviour and all the other facets of the report. Nonetheless, the sustainability recommendations appear to be based on a small number of papers, many of which are based on dietary information from other regions (Germany, UK, Italy) which will also have different levels of animal and crop production. As somebody who was born and bred in the UK before moving to the USA I find it difficult to believe that the average American’s diet uses substantially more land (for example) than the average UK person, as cited in the report.