The Future of Meat
Each year, humanity produces more than 310 million metric tons of meat.1 That entails raising and slaughtering billions of chickens, pigs, and cows and processing and distributing meat all over the world. The sheer volume of global livestock generates massive environmental impacts. Pasture land for cattle alone covers a quarter of the world’s land area,2 and the global livestock sector is responsible for about 14% of human-caused greenhouse gas emissions.3
It’s fair to say that producing food leaves the largest environmental footprint of any human activity, and meat plays a leading role.4 By mid-century, meat production is projected to rise by 42% over 2014 levels, to 450 million metric tons.5 Despite growing awareness of the impacts of meat production, global trends toward increased consumption remain robust.
In recent years, conversations about mitigating this impact have focused on two strategies: convincing people to eat lower on the food chain and shifting meat production toward more extensive systems. But a growing body of evidence suggests that the former may not prove particularly practical, while the latter may not always bring about better environmental outcomes, particularly at global scales. This essay considers trends in meat consumption and production to assess what sorts systems might be best equipped to mitigate the environmental impacts of global meat production.
Pulling the Demand Lever
Since at least the publication of Frances Moore Lappé’s Diet for a Small Planet in 1971, drastically reducing meat consumption has provided a common, if not a popular, prescription for addressing the food system’s environmental impacts. It is undeniable that eliminating meat consumption would obviate the need for meat production, and a variety of scientific studies confirm that eliminating meat from diets would reduce environmental impacts. For example, one study finds that substituting a vegetarian diet for current omnivorous diets could reduce future food system GHG emissions by 55%.6
There is little evidence, however, that growing environmental or health consciousness has appreciably influenced rates of vegetarianism. In the United States, the rate of vegetarianism falls somewhere between 3 and 5% of the population,7 a rate much the same as that of two decades ago (the earliest available data).8 Rates of attrition among vegetarians appear to be high,9 and one study found that two-thirds of those who described themselves as vegetarian also reported eating meat in the last day.10
More promising, perhaps, is “flexitarianism,” or a diet of reduced meat consumption, which may prove a more achievable goal for most than strict vegetarianism. In a 2015 poll, 36% of Americans reported that they eat at least one vegetarian meal per week, reflecting efforts to moderate meat consumption.11 In part for this reason, meat consumption has plateaued in affluent regions like Europe and North America, albeit at relatively high, but below peak, levels (Figure 1).
Figure 1. Regional Meat Consumption (per capita), 1961-2011
Data source: FAOstat
The composition of meat consumption in the United States has also shifted from predominantly beef to predominantly chicken, a trend driven by lower cost and health concerns.12 In the United States, per capita beef consumption has fallen 40% since its peak in the 1970s, while poultry meat has emerged as the most popular type of meat by far.13 The shift from beef to chicken gives rise to substantial environmental benefits, as chicken provides a much more environmentally efficient source of protein than beef. Producing a pound of chicken requires less than a quarter of the land and produces less than a quarter of the emissions than that for a pound of beef.14
Thus, in affluent economies with relatively high levels of health and environmental concern, efforts to moderate the impacts of meat consumption through behavior change might be best focused on moderating, rather than eliminating, meat consumption and encouraging consumption of less resource-intensive meats such as chicken and pork.
The majority of global meat demand growth, however, is projected to occur in Asia, Latin America, and Africa15 where not only are populations growing, but average meat consumption is well below developed country levels and rising strongly (Figure 1). Indeed, historically, meat demand tends to increase as incomes rise, a pattern nutrition researchers call the “dietary transition.” When people’s incomes rise from very low levels, they begin to increase their overall calorie consumption. As incomes rise further, they substitute away from simple starches towards refined carbohydrates like wheat, and from plant-based protein like beans towards animal products.16 Rachel Laudan, a food historian, explains that for many around the world, “Meat eating is not just a matter of taste or the environment, it’s a foothold, it’s a stake in the rich, modern world. It’s a sign that they too can leave behind the hierarchical societies of the past and be full citizens and enjoy what we already enjoy in the United States.”17
A meat market in Kolkata, India.
Although the dietary transition is visible worldwide, food is also a cultural product, and societal norms do impact patterns of meat consumption. Mongolia, for example, has unusually high meat consumption rates for its income level due to its tradition of nomadic livestock rearing. India, by contrast, has very low meat consumption because of the cultural and religious tradition of vegetarianism there. However, while beef and pork consumption remain taboo for many Indians, poultry consumption in India has risen considerably in recent decades.18
Given how robust the dietary transition has proven globally, it is reasonable to assume that global meat production will continue to increase as incomes rise in developing countries. Changes in meat-eating behavior in affluent countries have been modest so far, and consumption levels there remain much higher than in emerging economies. As such, successful efforts to significantly mitigate the environmental impacts of meat consumption will likely need to focus on meat production.
An Evolution in Meat Production
Although beef has the largest environmental footprint of any form of meat production, it is not in fact the most popular type of meat. Pork dominates global meat production, followed by chicken, with beef in third place.19 Additionally, large-scale beef production tends to conjure images of feedlot systems for many of us in the United States, but again, these systems are responsible for a minority of production globally: feedlot systems dominate in North America, while the rest of global beef is produced in extensive grazing systems.20 For pork and poultry production, on the other hand, intensive systems do already predominate globally.21
The distinctions between “extensive” and “intensive” meat production are manifold, from how animals are bred and housed, to what they are fed, to how their waste is handled. Most beef today is raised in extensive systems, where cattle graze on pasture areas, eating grass and other forages. Cattle have historically been highly valued in many societies because of this trait: they produce high-quality animal protein by grazing on lands that may not be suitable for growing crops.22
Unlike cattle, pigs and chickens cannot survive on grass. In extensive farming systems they are mostly fed locally produced crop residues or swill, rather than specially grown feeds.23 In this way, extensive livestock function as an integrated part of a broader agricultural system, feeding on waste products from crop production and providing manure for fertilizer.24 This integration provides advantages for producers, since the livestock produce both fertilizer and animal protein while requiring relatively few external inputs.
It was the tectonic economic and demographic shifts of the twentieth century that initiated an intensification of meat production in the United States and other Western countries. Rising wealth increased demand for meat, and new technologies like refrigeration and cold supply chains enabled centralized production and distribution. Labor shortages in the post-war era helped drive intensification as well: confined, indoor housing of animals required fewer workers, reduced problems from weather exposure, and sped up animal growth.25 With cattle production, a scarcity of grazing lands in the American West also contributed to the increased use of feedlots, and feeding cattle grain resulted in faster growth and more fat-marbled meat.26 Today, intensively managed livestock systems dominate in the United States for all meat types, and for pork and poultry production intensive systems dominate globally.27
US cattle ranchers in the early 1920s
These intensive livestock systems are defined by their reliance on external feeds that are nutritionally optimized to promote growth. For cattle, this means fattening the animals on grain- and soy-based feeds in feedlots during the last few months before slaughter. It should be noted, however, that even feedlot-finished cattle spend the first part of their lives on pasture.28 With intensive pork and poultry production, the animals are exclusively fed purchased feeds. Farmers also use selective breeding to optimize for size and rapid growth in intensive systems, and animals are kept in controlled, confined settings, often indoors.
While intensive systems are well-established in many wealthy countries, many emerging economies today are currently undergoing the process of intensification in response to burgeoning demand. For instance, China’s livestock sector, which already produces one-quarter of the world’s meat supply, has undergone rapid intensification in the past two decades to meet growing demand.29 The Chinese government has also incentivized consolidation among smallholder farmers, offering them subsidies to move their animals to “concentrated livestock raising areas” on the outskirts of town in order to facilitate better disease and environmental management.30
Many developing countries, however, are still in the early stages of the transition from traditional extensive livestock rearing. In the Horn of Africa, for instance, land fragmentation and urbanization have begun to put pressure on pastoral livestock systems. Pastoralists are responding by keeping their animals on smaller pasture areas and substituting away from cattle towards pigs, which require less land.31 This type of land pressure drove intensification in the United States in the early twentieth century, but without access to modern feeds and veterinary techniques, productivity remains very low in the Horn of Africa, with some plots hardly able to support livestock.32 The infrastructure and policy needed to enable successful intensification are not yet in place.
A cattle farmer in the Blue Nile Valley, Ethiopia (Tim E White / Alamy Stock Photo)
On the whole, extensive systems are being displaced by intensive ones throughout the world because intensive livestock systems offer higher productivity that can more easily meet demand from rapidly urbanizing, wealthier populations.33 Intensive livestock operations produce more meat, more quickly, and with fewer animals. Rather than requiring a nearby integrated farm environment, producers purchase commercial feeds and often house animals indoors. Specially formulated feeds promote faster growth,34 while the controlled environment reduces animal losses from disease and predation.35
This evolution of livestock production around the world “is shifting the balance of environmental problems caused by the sector,” explains the UN Food and Agriculture Organization (FAO) in its landmark report on the global livestock sector.36
Comparing Environmental Performance
At the global level, livestock’s environmental “hoofprint” is significant. Due to the high land demands and GHG emissions associated with beef production, beef is the main event as far as most environmental impacts associated with meat production are concerned. The vast majority of environmental impacts from beef production stem from extensive systems for the simple reason that the vast majority of beef is raised extensively.37 With pork and poultry production, on the other hand, intensive systems already predominate globally and are thus responsible for the majority of impacts.38
Broadly speaking, the higher productivity that characterizes intensive systems also often results in lower environmental impacts per pound of meat, especially when it comes to beef production. This positive relationship between productivity and environmental efficiencies points to the possibility of win-win outcomes for livestock intensification. Realizing that systems are likely to continue to intensify as meat demand rises in the coming decades, it will be important to understand these relationships and purposefully leverage them moving forward.
Greenhouse Gas Emissions
The difference in productivity between extensive and intensive production systems has major climate implications. Growing animals to slaughter weight faster can dramatically reduce emissions, most notably for beef. Fully two-thirds of all greenhouse emissions from global beef production consist of methane from enteric fermentation, a natural process that occurs during digestion.39 Cows belch out enteric methane emissions throughout their lifetime, so getting cows to slaughter weight faster also reduces the amount of time they are emitting methane. Intensive systems realize these environmental gains; in the United States, for example, grain-finished cattle take a fraction of the time to reach slaughter weight compared to grass-finished cattle.40 Feedlot-finished cattle are also usually larger than pastured cattle, which means each cow’s emissions are divided by a larger amount of meat.41
Producing feeds for intensive beef production also generates greenhouse emissions, but since animals only occupy feedlots for a short period, the added emissions from feed production are dwarfed by the savings from months of avoided enteric fermentation emissions.42 Feed emissions result from general agricultural practice (fertilizer production, machinery), but can also be attributed to land-use change if the feeds are sourced from a region undergoing deforestation for agricultural conversion.
When it comes to the question of emissions reductions, the role of carbon sequestration in cattle grazing has gained increased attention in recent years. Although well-managed pasturelands can help soils sequester carbon43 an equilibrium in soil carbon is reached fairly quickly,44 and the carbon benefits are not enough to offset the overall higher emissions in grazing-based ranching systems.45 Furthermore, the benefits of good pasture management can accrue to both grass-finished and feedlot cattle, since both spend time on pasture. Ultimately, due to the difference in productivity and thus in enteric fermentation emissions, feedlot-finished cattle generate fewer emissions per unit of meat than pastured cattle (Figure 2).
Figure 2. Emissions intensities of beef in the United States (emissions per unit of meat)
Pork and poultry production, on the other hand, complicate the emissions story. Since enteric fermentation does not occur in chickens and is very minimal in pigs, the majority of emissions associated with pork and poultry come from feed production and manure.46 (Only a relatively small portion of emissions originate in direct fossil fuel use, even in intensive systems—specifically, 17% of emissions for poultry and 12% for pork.)47 As with beef, using dedicated feeds in intensive production systems generates emissions but also improves productivity: the specially formulated feeds result in larger animals and a quicker time to slaughter. In extensive systems, lower-quality feeds are more difficult for animals to convert to body weight, which results in more volatile solids and nitrogen in their manure.48 Manure emissions are thus lower per pound of meat in intensive systems that use nutritionally optimized feeds.49
With poultry, these productivity gains outweigh the added emissions from feed production, and intensive systems win out with regard to emissions intensities (Figure 3). Pigs, however, take longer and require more feed to mature. As such, the productivity improvements of intensive systems fail to fully compensate for the added emissions from feed production when it comes to pork (Figure 3).
Figure 3. Global meat emissions intensities (emissions per unit of protein)
Data source: FAO GLEAM database
The relevance of the relationship between productivity and GHG emissions is best demonstrated with a regional example: the livestock sector in South Asia generates the same level of greenhouse emissions as North America, but produces only half the amount of protein.50 In extensive systems found in developing countries, animal mortality is generally higher, feeds are lower quality, and animals are slaughtered older and smaller, all of which increase emissions intensities.51 Many of the interventions producers would implement to improve their productivity would also result in decreased emissions intensities, demonstrating an important win-win characteristic of intensification.
Land use for livestock production is dominated by pastureland for cattle grazing, which covers a quarter of the world’s ice-free land.52 Unlike cattle systems, which require grazing areas, intensive pork and poultry systems require virtually no land for the animals themselves; their land demand almost exclusively takes the form of cropland for feed production.53 Given the need for pasture and the fact that cows are less efficient feed converters, beef has a far higher overall land-use intensity than pork or chicken (Figure 4).
Figure 4. Land-use intensity of meat production
(bars represent range of results from a literature review by de Vries & de Boer, 2010)
Data source: de Vries & de Boer (2010)
In all intensive livestock operations, the need for external feed presents a demand for crops and land to grow them that must be weighed against food security and biodiversity considerations. Today, about one-third of global cropland is used to produce feed crops.54 Soybean production for livestock feed becomes especially relevant in this regard because of its concentration in areas like the Brazilian Amazon that have undergone major deforestation in the wake of agricultural expansion.55 The added impacts of land-use change in systems that source feeds from high-deforestation areas can certainly outweigh the gains from higher productivity—this impact in fact explains the higher overall emissions associated with intensive pork production at the global level as shown in Figure 3.56 Additionally, since markets for livestock feed are global, any increase in demand can result in continued pressure for land conversion in deforestation regions.57 For example, while sourcing feeds from the United States may not result in direct deforestation, the increase in overall demand that it generates can displace production to regions where agricultural conversion is driving deforestation.
Nevertheless, there is some controversy over how much livestock should be held accountable for crop demand. With soybeans, for example, livestock are fed soybean meal, or the remains of soybeans after they are pressed for oil.58 Both soybean oil and meal are valuable commodities—they are considered co-products.59 Thus, livestock feed serves as a component of the demand for soybean meal, in combination with other food demand pressures. Demand for soy in virtually all cases cannot be attributed to livestock alone.
With beef production, land demand is primarily driven by the need for grazing area, even in intensive systems that also require cropland for feed production.60 In fact, feedlot-finished cattle require less overall land than grass-finished cattle, even when feed crop area is included (Figure 5). Providing cattle grain- and soy-based feeds during the last few months before slaughter accelerates the growth process and allows a given grazing area to support more cattle. Improving pasture quality with high-quality forages, fertilization, and irrigation can also increase productivity,61 which suggests that combining improved pasture and feedlot finishing could optimize land-use efficiency in beef systems.
Figure 5. Land requirements for grass-finished and feed-finished beef cattle
Feed production is the driver of virtually all freshwater consumption in livestock systems; the amount animals drink and the water needed for on-farm tasks is negligible in comparison.62 In some cattle systems, irrigating pasture to promote grass and forage production also results in significant water consumption.63
At the global level, beef again stands as the most intensive resource user: beef requires more water per pound of meat produced than either pork or chicken.64 In terms of “blue water” use (water extracted from surface and groundwater), extensive and intensive production systems vary in efficiency. The United States uses less blue water to produce beef and pork in intensive systems than in extensive ones, but the opposite is true at the global level (Figure 6).
Figure 6. Blue water consumption per metric ton of meat
Source: Mekonnen & Hoekstra (2012)
Regional differences in rainfall levels and irrigation practices drive these variations. In areas with high natural rainfall, less irrigation may be needed for crops or pasture, reducing blue water consumption.65 Irrigation is also expensive and requires technology that is not available to many farmers and ranchers in poor regions; in these settings, blue water consumption may be lower, but often so is productivity.66
There are also trade-offs between water use and other environmental impacts. For example, an irrigated pasture area can support more cattle because it increases forage production. In this way, increased water use can substitute for land. However, this trade-off may not pay off in arid regions where water is in high demand for food crop production; in those cases, larger unirrigated land areas may be preferable for cattle production.
Manure and Pollution
Animal manure is a final source of greenhouse gas emissions, as well as water pollution, in livestock systems. In extensive systems, manure is recycled as fertilizer for crop production or, with cattle, left dispersed in grazing areas. In intensive production systems, on the other hand, manure presents a pollution problem because it accumulates in a centralized setting. Concentrated manure generates ammonia emissions, which contribute to local air pollution.67 When manure piles are left exposed to the elements, rainfall can cause runoff into waterways, where the excess nitrogen from the manure can lead to algae blooms and create “dead zones” in coastal areas.68
Livestock manure is often left exposed to the elements as a least-cost option, but it can also be stored in a way that safely contains it before being processed or distributed as fertilizer. Anaerobic digesters provide one such form of containment—one that not only reduces pollution risks but also generates energy in the form of biogas—but the technology is not yet in widespread use. A regional example provides a model to follow in this regard: Denmark, a major meat producer for the EU, used a combination of regulation, subsidies, and producer innovation to successfully reduce nitrogen leaching without sacrificing productivity.70 As a result of better manure management techniques, including the practice of containing manure and using it for biogas production, nitrogen leaching in Denmark fell 48% below 1979 levels.71
Opportunities and Trade-offs in Regional Context
Given the sheer scale of global livestock production, how we produce and consume meat in the future will have a significant impact on our environmental future. However, trends in global demand for meat cannot be disentangled from the production systems used to meet that demand. Extensive systems depend on locally available crop residues for feeds, or natural forage production in grazing areas, which limits their ability to scale up production. As the FAO explains, “Extensive systems are incapable of meeting the surging urban demand in many developing countries, not only in terms of volume but also in sanitary and other quality standards.”72
Intensive systems offer higher productivity and scalability, and as a result, rising demand for meat has historically been coupled with increasing intensification. Certainly, shifting from extensive to intensive livestock production introduces new challenges, and the pace and management of the intensification process will be critical to ensuring positive results for producers and the environment. But if well-managed, intensification in the livestock sector has the capacity to leverage productivity gains that also generate environmental savings, helping to boost protein output while minimizing impacts.
Intensification, however, is not automatic or inevitable. Governments can and do promote intensification to increase production as well as improve oversight and management of environmental impacts and health risks. China, for example, has been rapidly intensifying its livestock sector as the country’s population grows and incomes rise.73 The shift towards concentrated production has been actively encouraged by government subsidies, in part to better manage local environmental and health impacts. The experience of bird flu in China demonstrated the manageability of disease control in larger intensive operations, as the majority of bird flu cases occurred in extensive systems.74
During an avian flu investigation, China FETP residents collect samples in a poultry market in Guangdong, China (CDC Globall)
Producers running intensive livestock operations have shown remarkable ability to adopt new techniques to boost productivity and reap environmental savings in the process. In the United States, for one, innovations in veterinary science, animal nutrition, and genetics have allowed for major improvements in the environmental performance of modern intensive beef production. Between 1977 and 2007, the land needed for beef production decreased 33%, water use decreased 12%, and the carbon footprint fell 16%.75 These improvements largely resulted from the continued shift towards feedlot finishing as well as from productivity enhancements like selectively breeding for larger animals and using improved feed formulations.76 Farmers and scientists are still working on ways to reduce impacts in commercial livestock production—for example, by experimenting with feed additives to reduce methane emissions from cattle.77
Accelerating the transition from extensive to intensive production should be prioritized in some cases to address environmental concerns. In Brazil, for instance, an explicit policy of intensification for the beef sector could help relieve pressure on land conversion. Most beef production there remains extensive (grazing only), so finishing beef cattle in feedlots would reduce the overall land demand from the cattle sector. Even if the cattle were fed soy grown in Brazil, the overall land use would be smaller than pasture-only cattle rearing. Considering that demand for pasture land is a key driver of deforestation in the Amazon, this shift could have a dramatic impact.78
Zebu cattle in Brazil, at a recently logged ranch on the edge of the Amazon rainforest. (Frontpage / Shutterstock)
Trade-offs and environmental impacts will vary by region, so context-specific solutions will be necessary. While feedlot finishing may prove a good option for the United States and Brazil, an arid region like Australia may deem it environmentally preferable to continue with a grazing-based system. Increased intensification in pork and poultry production will increase demand for dedicated feed crops in turn, which will require land-use and agricultural planning to minimize pressure on land conversion and competition with food supply. Managing the concentrated local impacts from intensive systems, like water pollution, will require responsible producers and robust regulation.
Looking ahead to the coming decades, continued intensification is likely as developing countries respond to rising demand. Thus, efforts to accelerate the adoption of best practice techniques from intensive management systems will be crucial to boost protein output and leverage environmental savings. No-regrets interventions like optimized breeding, nutrition, and veterinary care can improve animal survival, shorten time to slaughter, and increase productivity, benefiting both producers and the environment. In industrialized countries, ongoing innovations are needed to continue raising the bar for environmental performance in modern intensive systems.
Animal Welfare and Livestock-Free Meat
Environmental impacts are, of course, not the only consideration; for many people, concerns over animal welfare outweigh concerns about emissions or productivity. Conditions like high stocking densities, confinement, and lack of outdoor access can restrict natural animal behaviors and are common in many intensive livestock systems. While trade-offs do exist between improving animal welfare, reducing environmental impacts, and increasing productivity, however, there are also some synergies. Because poor animal welfare can lead to the spread of disease and lower quality meat, for instance, producers share an interest in the wellbeing of their animals.79
Many of the practices that drive efficiency in intensive systems do not come at the expense of animal welfare or environmental impacts. Breeding for larger animals allows for more meat to be produced with fewer animals, which becomes starkly obvious when comparing the size of livestock in poor countries to those in modern livestock operations (although selective breeding can also be taken to an extreme when animals are rendered virtually handicapped).80 Nutritionally optimized feeds and regular veterinary care (including judicious use of antibiotics) boost productivity and ensure animal health. Many of the practices that draw objections from an animal welfare perspective, like unhealthy manure accumulation and extreme confinement, can be improved upon without major consequences for productivity,81 although they do usually come at some cost.82
A US Public Health Service veterinarian injects a cow with an anti-parasite vaccination in Nicaragua.
Researchers are also developing technological innovations to improve animal welfare; for example, a scientific innovation called in-ovo sexing may eliminate the need to kill male chicks in the egg industry84 and a gene-edited dairy cow has been bred without horns, which would normally be painfully removed.84 On the other hand, some interventions intended to improve animal welfare in large-scale operations have led to unintended consequences: commercial egg producers who have shifted to cage-free production have seen an increase in bird mortality, hazardous working conditions, and particulate emissions.85 This serves as a reminder that confinement in industrial systems originated partly from the motivation to protect animals from one another and from disease.86
Ultimately, animal health or poor treatment are both possible in extensive, industrial, and organic farms alike. As Temple Grandin, an animal scientist who works on animal welfare in the livestock industry, says, “People get into, ‘big is bad, small is good.’ It’s not that simple. The key is management. Whether you are big or small, you’ve got to have good management.”87 Even with good management, some may still see commercial livestock production as inhumane. Consumers, farmers, and societies will have to determine the right balance between animal welfare, cost, and environmental performance of livestock systems based on their own values, while also taking into account the growing demand for meat worldwide.
Thinking in the very long run, there is exciting research to support the prospect of producing meat without livestock. The idea behind “cultured meat” is to grow meat from animal muscle cells in culture, producing a genuine animal product without the animal.88 Although this technology currently exists only at the laboratory scale, many researchers and animal-rights activists have set their sights toward to scaling up to commercial production, the way we have with beer, cheese, and other beloved cultured products. Many startups are also working on commercializing milk, eggs, and ground beef made without animals. Bruce Friedrich of the Good Food Institute believes consumers will come around to the idea of cultured meat: “Right now people eat meat despite how it's produced, not because of how it's produced.” In the future, he says, it will be “absurd to use live animals to create meat.”89
Breakthrough tried the "Impossible Burger," the vegan burger that bleeds, in San Francisco last month.
Additionally, although plant-based meat alternatives have historically held a low market share compared to meat,90 new innovations have improved the texture, taste, and appearance of plant-based meat substitutes. The “Impossible Burger” developed by a Silicon Valley start-up “bleeds” like real beef and is now being launched at trendy restaurants in New York, San Francisco, and Los Angeles.
The Future of Meat
In a world where billions of people want meat on their plates, the environmental impact of livestock is significant, and could grow as populations and incomes rise in the coming decades. It is tempting to obviate the need for a growing livestock sector by envisioning a more vegetarian future. Meat consumption in many wealthy countries has indeed plateaued or even fallen below its peak, and many consumers there engage in moderation of meat consumption for health or environmental reasons. These trends are encouraging, and indicate that meat demand need not rise indefinitely. However, meat consumption in many parts of Asia and Africa still sit well below levels in North America or Europe, and the robust historical trend of the dietary transition suggests that global meat demand is likely to continue to grow significantly before plateauing.
The extensive livestock systems that still predominate in many developing countries are not equipped to scale up production to meet rising demand from larger, more urban, and wealthier populations. As a result, livestock sectors in many developing countries are shifting toward the intensive systems that dominate in wealthy countries. Intensive systems offer high productivity, but also come with their own, often more concentrated, environmental impacts. Nevertheless, a comparison of impacts per unit of meat highlights that the productivity gains in intensive systems can and do often yield environmental savings. This positive relationship between productivity and environmental performance is a crucial insight, and subverts the common perception that more intensive production is necessarily worse for the planet.
All livestock systems come with trade-offs, and meat remains a resource-intensive (albeit popular) foodstuff around the world. As one of many modernization processes occurring in developing countries today, intensification of the livestock sector offers huge opportunities to boost protein availability while minimizing environmental harm. Best practices and innovations in animal science and management have the potential to further optimize these outcomes.
Ultimately, the conventional narrative around livestock production deserves an update, one that reflects the realities of demand, productivity, and environmental performance in modern livestock systems. If societies are to satisfy consumers’ demand for meat while minimizing the real-world environmental consequences of livestock production, they will undoubtedly need to acknowledge and leverage the efficiencies of intensive systems.
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