REVIEW SUMMARY

FOOD SECURITY

Meat consumption health andthe environmentH Charles J Godfray Paul Aveyard Tara Garnett Jim W Hall Timothy J KeyJamie Lorimer Ray T Pierrehumbert Peter ScarboroughMarco Springmann Susan A Jebb

BACKGROUND The global average per capitaconsumption of meat and the total amountof meat consumed are rising (see the figure)drivenby increasing average individual incomesand by population growth Growth rates varyacross different regions with consumption inhigh-income countries static or declining and inmiddle-income countriesmoderately to stronglyincreasing whereas in low-income countriesmeat consumption is on average low and stableThere has been a particularly marked increasein the global consumption of chicken and porkThe consumption of different types of meatand meat products has substantial effects onpeoplersquos health and livestock production canhavemajor negative effects on the environment

ADVANCES Meat is a good source of energyand some essential nutrientsmdashincluding pro-tein andmicronutrients such as iron zinc andvitamin B12mdashalthough it is possible to obtain asufficient intake of these nutrients withouteating meat if a wide variety of other foodsis available and consumed In high-income

Western countries large prospective studiesand meta-analyses generally show that totalmortality rates are modestly higher in partici-pants who have high intakes of red and pro-cessedmeat The strongest evidence of a specificadverse effect is the increased risk of colorectalcancer with high intakes of processed meatMeat produces more emissions per unit of

energy compared with that of plant-basedfoods because energy is lost at each trophiclevel Within types of meat ruminant pro-duction usually leads to more emissions thanthat of nonruminant mammals and poultryproduction usually leads to less emissionsthan that of mammals Meat production is thesingle most important source of methanewhich has a relatively high warming potentialbut a low half-life in the environment com-pared with that of CO2 Careful managementof grassland systems can contribute to car-bon storage but the net benefits are likely tobe relatively modest Agriculture uses morefreshwater than any other human activitywith nearly a third required for livestock so

meat production in water-stressed areas is amajor competitor with other uses of waterincluding that required to maintain naturalecosystems Meat production can be an im-portant source of nitrogen phosphorus andother pollutants and affects biodiversitymdashinparticular through land conversion to pas-ture and arable feed crops

OUTLOOK Governments act to shape foodsystems for economic purposes and to pro-tect health from contaminated food But thereis less agreement over the degree to whichthe state should use health environmental oranimal welfare considerations to control the

supply of meat throughinterventions that affectthe production sale pro-cessing and distributionof meat and meat pro-ducts or the price to theconsumer

If we are to shape consumer demand moreevidence is needed about the effectiveness ofdifferent interventions to influence food se-lection This may include interventions thataffect either the conscious reflective decision-making systems or nonconscious automaticprocesses Potential interventions within therational choice paradigm include labelingschemes (based on health or environmentalcriteria) and certification programs (based onwelfare or environmental considerations) orfiscal interventions (such as so-called fat taxes)Alternatively the largely automatic responsesto environmental cues that affect purchaseand consumption behaviors can be manipu-lated by changes to the food environment inretail and food consumption settingsHistory suggests that change in dietary be-

haviors in response to interventions is slowBut social norms can and do change andthis process can be aided by the coordinatedefforts of civil society health organizationsand government However successful inter-ventions to improve health and environmentalobjectives are likely to require a good under-standing of the impact of meat consump-tion on these outcomes as well as a licensefrom society for governments and other bodiesto implement a suite of interventions to stim-ulate change

RESEARCH

Godfray et al Science 361 243 (2018) 20 July 2018 1 of 1

The list of author affiliations is available in the full article onlineCorresponding author Email charlesgodfrayoxfordmartinoxacukCite this article as H C J Godfray et al Science 361eaam5324 (2018) DOI 101126scienceaam5324

Total consumption of meat (in million metric tons) in different regions and (inset) glob-ally [Data are from wwwfaoorgfaostatendata]

TOMORROWrsquoS EARTHRead more articles onlineat scimagTomorrowsEarth

ON OUR WEBSITE

Read the full articleat httpdxdoiorg101126scienceaam5324

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REVIEW

FOOD SECURITY

Meat consumption health andthe environmentH Charles J Godfray12 Paul Aveyard134 Tara Garnett156 Jim W Hall15Timothy J Key17 Jamie Lorimer18 Ray T Pierrehumbert19 Peter Scarborough110Marco Springmann110 Susan A Jebb13

Both the global average per capita consumption of meat and the total amount of meatconsumed are rising driven by increasing average individual incomes and by populationgrowth The consumption of different types of meat and meat products has substantialeffects on peoplersquos health and livestock production can have major negative effects on theenvironment Here we explore the evidence base for these assertions and the optionspolicy-makers have should they wish to intervene to affect population meat consumptionWe highlight where more research is required and the great importance of integratinginsights from the natural and social sciences

The amount of meat in human diets variesgreatly among individuals within societiesand across different societies At a globallevel both the average per capita consump-tion of meat and the total amount of meat

consumed are rising driven by increasing averageindividual incomes and by population growth (1)More detailed analysis shows that there have beenmajor changes in the type of meat we eatmdashin par-ticular large increases in chicken and pork con-sumption (1) In addition a greater fraction of themeatwe eat today is processed before purchase (1)Trends in the demand for meat matter for

many reasons Meat can be an important sourceof nutrients for people on low incomes withrestricted diets but there is also evidence thathigh meat consumption may increase the riskfor some types of chronic disease (2) Meat pro-duction is one of the most important ways inwhich humanity affects the environmentWe cutdown forests to create pasture as well as arableland to meet the demand for animal feed (3)

Livestock production is a major source of green-house gases (GHGs) and other pollutants in someareas makes major demands on scarce waterresources (4) and can exacerbate soil erosionBut livestock also provide employment for largenumbers of people and the trade in livestock andrelated food products is a core component of theeconomies of many countries (5)Policy-makers are increasingly grappling with

the economic health and environmental con-sequences of rising meat consumption It is notclear the degree to which policy-makers have thesocietal license to intervene to influence meatconsumption and if they do what interventionsmight be effective These issues are particularlycomplex given the multiple narratives abouteating meat that influence everyonersquos behaviorThis Review explores these intersecting drivers

and attempts to place the natural science issuessuch as the effects ofmeat consumption on healthand the environment in the context of the po-litical economy and social factors that simulta-neously determine individual behavior and policyformulation

Present and future meat consumption

Meat consumption at the population level can beestimated by using self-reported dietary surveyswhich provide rich detail but are expensive toconduct (6) In practice not all countries haveaccess to this type of data and therefore foodbalance sheets derived from national agricul-tural and trade accounts are often used to providean estimate of food availability from which con-sumption can be estimated (7) A key strengthof this approach is that the same methodologycan be applied tomost countries providing cover-age and standardization Its weakness is that itdoes not directly measure consumption of indi-viduals and adjustments have to be made forwaste (8) Also it focuses on primary commoditiesand not the processed and composite foods that

are eventually consumed This is a particular issueformeat products because of the differential healtheffects of processed and unprocessed meat (9)Using food balance sheet data the average

global consumptionof allmeat has been estimatedto be 122 g dayminus1 of which a third each is pork andpoultry a fifth is beef and the remainder fromsheep goats and other animals (Fig 1) (1) Con-sumption has plateaued and possibly even de-creased in high-income countries whereas it hasrisen dramatically inmanymiddle-income coun-tries especially in China and East Asia althoughnot India perhaps because of the long traditionof vegetarianism among some communities Theamount ofmeat consumed inAfrica has remainedrelatively low on average and in a few countrieshas declined although in some pastoral com-munities meat and dairy constitute a very largeproportion of the diet (10) There have also beenmajor changes in the types of meat consumed inmany regions typically more chicken at the ex-pense of beef and more processed meats (1)Micha et al (11) recently collated 266 individ-

ual dietary surveys from 113 countries in order toestimate the global consumption of redmeat andprocessed meat for the Global Burden of Disease(GBD) project The 2010 global average per capitaconsumption of 42 g dayminus1 unprocessed red meatand 14 g dayminus1 processed meat (which includesboth red and white meat) hides great regionaldifferences with high-income (60 to 91 g dayminus1)and Latin American (27 to 44 g dayminus1) countrieseating themost and Africa (7 to 34 g dayminus1) andAsia (4 to 7 g dayminus1) eating the least Food balancesheets from the same year indicate higher redmeat consumption (~68 g dayminus1 after adjustingfor waste) although this includes some processedmeat (8) Considering thedifferentmethodologicalassumptions the two approaches agree reason-ably wellA well-established empirical relationship known

as Bennettrsquos law (12) shows that as people becomewealthier their diets change from being largelybased on starchy staples to diets that incorporateincreasing amounts of refined grains fruit vege-tables meat and dairy (13) The degree to whichthese food types become incorporated in dietsdepends on their relative costs To project dietsinto the future some researchers have adopteda statistical approach that is based on relation-ships such as Bennettrsquos law and expected futureeconomic growth Such studies have suggestedthat the rise in wealth will lead to an increase inmeat consumption of ~100 between 2005 andmid-century (14) A different approach is to at-tempt to model the economic dynamics of thefood system (typically by using partial equilibriummodels) A review of such models suggested thatgrowth in the demand for livestock productswould increase by 62 to 144 (15) bymid-centuryA major review by the Food and AgricultureOrganization (FAO) of the United Nations (16)which makes extensive use of expert judgementprojects an increase of 76 in the total quantityof meat consumed by mid-century This includesa doubling in the consumption of poultry a 69increase in beef and a 42 increase in pork (16)

RESEARCH

Godfray et al Science 361 eaam5324 (2018) 20 July 2018 1 of 8

1Oxford Martin Programme on the Future of Food OxfordMartin School University of Oxford 34 Broad Street OxfordOX1 3BD UK 2Department of Zoology University of OxfordSouth Parks Road Oxford OX1 3PS UK 3NuffieldDepartment of Primary Care Health Sciences University ofOxford Radcliffe Observatory Quarter Woodstock RoadOxford OX2 6GG UK 4NIHR Oxford Biomedical ResearchCentre Oxford University Hospitals NHS Foundation TrustOxford OX4 2PG UK 5Environmental Change InstituteUniversity of Oxford South Parks Road Oxford OX1 3QY UK6Food Climate Research Network Environmental ChangeInstitute University of Oxford South Parks Road Oxford OX13QY UK 7Cancer Epidemiology Unit Nuffield Departmentof Population Health University of Oxford Richard DollBuilding Roosevelt Drive Oxford OX3 7LF UK 8School ofGeography and the Environment University of Oxford SouthParks Road Oxford OX1 3QY UK 9Department of PhysicsUniversity of Oxford Clarendon Laboratory Parks RoadOxford OX1 3PU UK 10Nuffield Department of PopulationHealth University of Oxford Old Road Campus HeadingtonOxford OX3 7LF UKCorresponding author Email charlesgodfrayoxfordmartinoxacuk

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Although differing in details the various studiesall agree that there will be a substantial increasein the demand for meatSeveral uncertainties may affect these projec-

tions including socioeconomic change productivi-ty growth and climatic drivers and the preciserelationship between demand formeat and risingincome in different geographical regions Demandfor meat has both an economic and cultural basisunderstanding how societal norms and narrativesconcerning meat consumption will evolve is bothimportant and challenging to quantify But thereis widespread agreement thatmost of the increasein meat consumption will occur in low- andmiddle-income countries

Drivers of meat consumption

Understanding the reasons why we purchaseand consume specific types of food is critical ifwe seek to improve health and environmentaloutcomes For a minority of people there maybe no alternative to diets very high in meat andother animal-sourced food Nomadic pastoralistsin desert and semidesert environments and tradi-tional Inuit communities in the Arctic can onlyfarm or hunt animals because they have limitedopportunities to grow or purchase other types offood In other populations many people are toopoor to buymore than small amounts ofmeat Butfor a large proportion of the global populationthe price of meat today relative to their averageincome is less than it has ever been in historyMany factors in addition to price influence

decisions to consume meat Innate food prefer-ences probably evolved in an environmentwherefood scarcity was a constant risk An intrinsicdesire for energy-dense and nutrient-rich foodsuch as meat once promoted survival but todaymay predispose us to the diseases of overcon-sumption (17 18)Biological factors interact with a variety of

psychological determinants to shape diets Wemake decisions about purchasing meat based

not only on affordability but also on other fac-tors such as availability or convenience (to buyor cook) and its social and cultural value Thefood we buy and share influenced by our beliefsand values is part of the way we construct ourown identities In addition to deliberative think-ing the subconscious mind influenced by theforce of habit and societal norms influencespatterns of meat consumption (19)Economics and political economy also influ-

ence diets Livestock constitute 40 of agricul-tural output by price andmeat production andprocessing and retailing is a substantial eco-nomic sector in most countries The sector hasconsiderable political influence andallocates largeamounts of money to advertising andmarketingLobbying from the meat industry was intensiveduring the formulation of US Dietary Guide-lines and civil society organizations claimed thatthis influenced eventual recommendations (20)Nonstate bodies seek to influence policy onmeatand other food types often by developing alter-native narratives that resonate with sections ofthe public Issues raised include animal welfarethe idea of what is ldquonaturalrdquo and how produc-tion systems accord with worldviews on econom-ic equity and globalization versus localizationThis complex of competing narratives containsand is influenced by public health and environ-mental policy concerning diets

Effects on health

The main approach to estimating the impacts ofmeat consumption on long-term health is throughprospective epidemiological cohort studies inwhich tens of thousands of participants reporttheir dietary intakes and their health is fol-lowed over many years in order to identify theassociations between meat consumption andrisk of disease The results of these studies haveto be interpretedwith great care so as to allow forpotential confounding factorsMeta-analyses thatcombine the results of individual cohort studies

can provide summary estimates but will not bereliable if they combine results from dissimilarstudies and are subject to the same potentialbiases as the original studies (21) Randomizedcontrolled trials in humans are extremely difficultto conduct especially overmore than a fewweeksor months so it is difficult to measure the long-term effects on health while the interpretation ofthe human health relevance of trials in non-human animals is challengingMeat is a good source of energy and a range of

essential nutrients including protein and micro-nutrients such as iron zinc and vitamin B12 It ispossible to obtain a sufficient intake of thesenutrients without eatingmeat if a wide variety ofother foods is available and consumed (22 23)However in some low-income countries accessto alternativenutrient-dense foodsmaybe limitedtherefore diets low in meat may have negativehealth impacts (24 25) Approximately 35 ofpeople in India are vegetarians but the impact ofvegetarianism is not well documented althoughthere is some evidence that Indian vegetarianshave a slightly more favorable cardiovascularrisk profile than that of nonvegetarians (26)In high-income Western countries large pro-

spective studies andmeta-analyses generally showthat total mortality rates are modestly higher inparticipants who have high intakes of both redand processed meat than in those with low meatintakes whereas no or moderate inverse associa-tions have been observed for poultry (27ndash30)However part of this may be due to the associa-tion of high meat intakes with other major riskfactors such as smoking alcohol consumptionand obesity because the information needed toremove statistically the influence of these con-founding factors may not be availableThe strongest evidence for an adverse effect

of high meat intakes on health is for colorectalcancer (Fig 2A) TheWorldHealth OrganizationrsquosInternational Agency for Research on Cancer(IARC)has classifiedprocessedmeat as carcinogenic

Godfray et al Science 361 eaam5324 (2018) 20 July 2018 2 of 8

Fig 1 The economics of meat production (A) The value of livestock(globally and by region) as a proportion of total agricultural value in 2014Numbers above bars are absolute values in billion dollars adjusted forpurchasing parity power using constant 2006 dollars (1) (B) Growth of

exports of soya feed for livestock from South America to China (1)(C) Predicted change in price and consumption of different food typesafter the introduction of a globally uniform tax related to GHG emissionsMeat products are some of the most strongly affected food types (94)

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to humans because of an association with colo-rectal cancer and red meat is classified asprobably carcinogenic to humans again basedmainly on evidence of links to colorectal cancer(9) IARC estimates that 34000 cancer deathsper year worldwide are attributable to diets highin processed meat and if the reported associa-tions with red meat were proven to be causalthen diets high in red meat could be responsiblefor 50000 cancer deaths per year worldwide (31)The average intake of processedmeat inWesternEurope [264 g dayminus1 (11)] would based on theIARC analysis lead to a 9 [95 confidenceinterval (CI) 5 to 14] increase in colorectalcancer risk High intakes of processed meat mayalso increase the risk for stomach cancer butthere is no strong evidence that it increases therisk for other types of cancer (32)Processed meat consumption also seems to be

associated with risk for several other diseasesalthough the evidence is not conclusive For ex-ample a recent meta-analysis reported that highintakes of processed meat (but not unprocessedredmeat) are associatedwith amoderate increasein the risk for mortality from cardiovasculardisease (Fig 2B) (27 30) Some studies have alsosuggested that high intakes of processed meat

are associated with an increased risk for otherchronic diseases such as diabetes (33) and withweight gain in adults (34) Few cohort studieshave examined the associations of meat intakewith health in non-Western countries In high-income Western countries a lower meat intakemay be a marker of a health-conscious lifestylebut in low-income countries lower meat intakesare more likely to be markers of poverty and as-sociated with other risk factors for poor healthIn a pooled analysis of Asian studies and a re-cent cohort study in Iran meat intake was sub-stantially lower than in the United States andwas not associated with risk of overall mortalityormortality from cardiovascular disease or cancer(35 36)It is not yet understood how colorectal cancer

risk is increased by high consumption of pro-cessed meat or red meat Components in meatthat might be carcinogenic include heme ironN-nitroso compounds in many processed meatsand heterocyclic aromatic amines and polycyclicaromatic hydrocarbons which are formed whenmeat is cooked at high temperatures (9) Severalmechanisms could also underlie the observed as-sociation between high meat intakes and risk forcardiovascular disease For example red and pro-

cessedmeatsmight increase risk because they areusually rich in saturated fatty acids which raiselow-density lipoprotein cholesterol and processedmeat might also raise blood pressure because it isusually high in salt other mechanisms could beinvolved such as the generation of trimethyl-amineN-oxide fromL-carnitine inmeat (33 37)Further research is needed on the effects of

meat on health in low- and middle-incomecountries and on the role of substitute plantfoods such as pulses For US cohorts severalstudies have found significantly lower risk ofcoronary heart disease (38) stroke (39) type 2diabetes (40) and all-cause mortality (41 42) instatistical analyses that model replacement ofanimal sources of proteinmdashin particular red andprocessed meatmdashwith plant sources of proteinsuch as nuts pulses and whole grains Modelestimates that included individual risk coef-ficients for meat- and plant-based productsfound that transitioning from high meat to moreplant-based diets might reduce global mortalityrates by 6 to 10 if the associations modeled arecausal (43)Currently various national and international

bodies recommend an upper limit of meat con-sumption formaintaininggoodhealthForexample

Godfray et al Science 361 eaam5324 (2018) 20 July 2018 3 of 8

Fig 2 Meat and health (A) Therelative risk of colorectal canceras a function of average pro-cessed meat intake [from (95)](B) The relative risk ofcardiovascular death as afunction of average processedmeat intake [from (27)]

Fig 3 Meat and climate change (A) GHGemissions from the production of differentfood types in 2005ndash2007 and projections for2050 (assuming an emissions pathwaythat would keep global temperatures below2degC) The y axis is the percentage of totalGHG emissions Animal-sourced foods are themajor source of food-system GHGs andtheir relative importance is likely to increase inthe future (43) (B) The three major GHGs havequite different effects on climate The figureshows the effect on climate warming of each gasif emissions at the current rate produced bylivestock operations were introduced inYear 0 and thereafter held fixed indefinitely[methodology from (54)] The warming due tomethane is substantial and rises quickly butbecause of the gasrsquos short residence time in the atmosphere ceasesgrowing after about two decades whereas the warming due to carbondioxide continues to grow throughout the two centuries shown and indeedwould continue to grow indefinitely so long as emissions continue Thewarming due to nitrous oxide has begun to level off at the end of the two

centuries and grows little in subsequent years Although the warming inresponse to a fixed methane emission rate levels off rather quickly anincrease in the rate of methane emissions caused by an increase inlivestock production would still cause proportionate increases in themethane-induced warming

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the World Cancer Research Fund recommendsthat peoplewho eat redmeat should consume lessthan 500 g a week and population average con-sumption should not exceed 300 g aweek in eachcase minimizing the fraction that is processedmeat (44) Other initiatives such as the GBDproject suggest a desirable intake of no morethan one 100-g portion a week to reduce thedisease burden related to meat consumption (2)We have concentrated here on the nutritional

effects ofmeat on human health butmeat is alsoa potential source of various foodborne infec-tions (45) Livestockmay in addition act as reser-voirs for pathogens that can also infect humansa particular problem where humans and farmedanimals come into close contact (46 47) Fur-thermore antibiotics are used widely in meatproduction both as veterinary medicines and asgrowth promoters There is serious concern thatgenes for antibiotic resistance may be selected inagricultural settings and then transferred tohuman pathogens (48)

Effects on the environment

The question of whether producingmeat is moreor less harmful to the environment than otherfood types is complex because of the variety ofmeat production systems because meat produc-tion may or may not compete for resources thatcould be used to produce other food types andbecause it depends critically on how harm to theenvironment is measured (43 49 50)Over the past two decades multiple life-cycle

analysis studies have sought to assess the GHGemissions of different types of meat productionsystems (51 52) Meat produces more emissionsper unit of energy compared with plant-basedfoods because energy is lost at each trophic level(Fig 3A) Within types of meat ruminant pro-duction usually leads to more emissions thanthat of nonruminant mammals and poultryproduction leads to less emissions than that ofmammals The type of production system is im-portant Intensive rearing tends to produce fewerGHG emissions than more extensive systems perunit of output (although they can bringwith themother important disadvantages)The most important anthropogenic GHGs are

carbon dioxide (CO2) methane and nitrous oxide(N2O)Meat production results in the emissions ofall three and is the single most important sourceof methane (51 53) Using the composite measureof CO2 equivalents (CO2e) livestock production isresponsible for ~15 of all anthropogenic emis-sions (51) But calculation of CO2e coerces emis-sions of the three onto a common scale whichcan be misleading because of their different resi-dence times in the atmosphere For CO2 cumula-tive emissions are key whereas for methane it isthe rate of emission (Fig 3B) (54) Currentlylivestock contributes ~5 of the nearly 37 gigandashmetric ton of CO2 human activities add to theatmosphere each year Thirty-seven hundredgigandashmetric ton cumulative emissions are esti-mated to cause 2degC warming therefore 100 yearsof livestock CO2 production at current rateswouldlead to a measurable but comparatively small

increment to global warming (~01degC) Meat pro-duction currently adds 015 gigandashmetric ton ofmethane and 00065 gigandashmetric ton of N2O tothe atmosphere annually If the climate systemis allowed to reach equilibrium with this levelof GHG emission and decay (which would takeabout a decade for methane and about a centuryfor N2O) then the earth would be 044degC warm-er When this equilibrium is reached continuedemissions of methane and N2O at the same leveldo not result in further warming CO2 is differentbecause its effect on warmingwill grow as long asCO2 releases continue even if the emissions ratedoes not increase These estimates suggest thatmeat production really matters in calculations offuture global warming but that distinguishing theeffects of the different types of GHGs is very im-portant for policy-makers (54)About 4 of all meat and 8 of beef are

produced in grass-fedndashonly extensive systems(grass is also used as a feed source in mixedsystems) (55) Grazing has a complex effect oncarbon budgets it can stimulate plants to al-locate more resources below ground which helpssequestration and livestock excreta can promoteplant growth and carbon fixation by makingnitrogen more available to the next generationof plants (although some of this nitrogen is lost

through N2O emissions) (51 56) But this has tobe balanced against direct GHG emissions fromanimals the indirect emissions caused by over-grazing and erosion and alternative potentialuses for the land including for carbon seques-tration via natural plant growth or afforestationMajor claims have beenmade for the potential oflivestock production by grazing to be amajor netbenefit for climate change by promoting CO2

storage (57) however careful analyses have shownthat the estimated benefits are highly localityspecific and that at a global level the benefitsare modest at best and outweighed by the emis-sions that the animals produce (56 58 59) Grass-lands do store carbon but the further amountthey can sequester depends on how much theyalready hold and eventually sequestration stopswhen gains are balanced by losses due to leach-ing microbial respiration and other processesPoormanagement natural events suchasdroughtsor fires and land-use change can quickly releasethe carbon back into the atmosphere (60) Carefulmanagement of grassland systems can contributeto mitigating climate change but the net benefitsare likely to be relatively modestAgriculture uses more freshwater than any

other human activity and nearly a third of this isrequired for livestock (Fig 4A) (61) Water used

Godfray et al Science 361 eaam5324 (2018) 20 July 2018 4 of 8

Fig 4 Meat and the environment (A) The proportion of global freshwater withdrawals (outof a total of 4001 km3 yearminus1) used in agriculture for arable (directly) and livestock (of which most isused to grow crops to feed animals) industry and energy and in the municipal and domestic sectors[Data are from FAO AquaStat 2016 wwwfaoorgnrwateraquastatmainindexstm] (B) Use ofantibiotics in agriculture in different countries [expressed as milligrams of antibiotics per kilogram ofmeat PCU (population correction unit) to allow comparison] [Data are from (96)] (C) Fate ofdeforested land in Mato Grosso Brazil ldquoSmall area conversionrdquo refers to areas lt25 ha (97)

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in livestock production is largely (872) ldquogreenwaterrdquomdashrain and other precipitation that fallsdirectly on the land (4) Although ldquoblue waterrdquowithdrawals for livestock productionmdashfrom riverslakes and groundwatermdashare only 7 of green-water use they are particularly important becausethey compete more directly with other uses ofwater including that needed for themaintenanceof aquatic ecosystems Water used for growinganimal feed accounts for 98 of the total waterfootprint of livestock production with livestockdrinking water service water and feed-mixingwater accounting for only 11 08 and 003 ofthe total water footprint respectively (4) The ef-fects of blue water withdrawals can have sub-stantial impacts on water resources such as inthe High Plains aquifer in the central UnitedStates where increasing production of cattle fedwith irrigated corn is resulting in severe aquiferdepletion (62) Unlike GHG emissions which havethe same climatic effect irrespective of where theyare emitted the impact of water use depends onthe water source location and season duringwhich water is used There is also considerablevariation in water footprint among types of meatand production systems although on averagebeef farming is more than three times as waterintensive as chicken production per kilogramof meat (4 63)

Nitrogen and phosphorus in animal manurecontribute to nutrient loads in surface andgroundwater harming aquatic ecosystems andhuman health (64) Manure lagoons used inintensive livestock productionmdashwhich containnutrients toxins and pathogensmdashare a con-centrated contamination risk for surface andground waters (65) Diffuse nutrient loadingfrom pastoral livestock production dependson stocking rates proximity to water bodies andland management practices (such as the pres-ence of vegetation strips along water bodies)(66) Given a particular level of meat productionusing animal manure as a substitute for artificialfertilizers which require large amounts of energyto manufacture helps lower GHG emissions (al-though reducing the levels of GHG-intensivemeatproduction is always a more efficient strategy)Themost substantial direct way inwhichmeat

production affects biodiversity is through landconversion to agriculture (Fig 4C) (3) This in-volves both conversion of natural habitats tograssland and grazing and conversion to arableland to produce grain and soya for livestock con-sumption De Sy and colleagues (67) estimatethat ~71 of rainforest conversion in SouthAmerica has been for cattle ranching and afurther ~14 for commercial cropping includingsoya for animal feed (pastureland is often sub-

sequently converted to cropland) (68) In thepast 20 years exports of soya from South Americato China (and other countries) have increaseddramatically and now constitute one of the largestinternational commodity flows (Fig 1B) Livestockproduction also affects biodiversity through over-grazing with especially deleterious impacts indrylands (69) These ecosystemswould have beengrazed by wild herbivores but the much higherofftake from livestock changes and reduces plantspecies diversity The reduced plant cover andtrampling on slopes leads to soil erosion and tofurther biodiversity loss There has been consid-erable study of what combinations of wildlife andlivestock densities best promote biodiversity indifferent ecological settings and in some caseswhere native herbivores are no longer presentor extinct livestock can help or be essential tomaintain natural ecosystems (70) But in manydeveloping countries the understandable pres-sures from poor people needing to produce foodlead to a vicious circle of unsustainable over-grazing and an increasing demand for grazinglandLivestock production may also affect bio-

diversity through shared diseases For examplelions in the Kruger National Park in South Africaare threatened by bovine tuberculosis whichthey contract from the buffalo they eat whichin turn are infected by domestic livestock (71)But these effects need not always be negativeThe global elimination of rinderpest was carriedout to protect livestock yet wild ungulates alsobenefit from the eradication of this disease (72)

Changing diets

Studies of how people justify to themselvesthe consumption of meat show that belief thatit is ldquonatural normal necessary or nicerdquo explainsthe large majority of variance in consumption(73) Precisely because meat consumption is aldquonormalrdquo part of the diet often the routine centerof themainmeal the ldquochoicerdquo to consume it goeslargely unexamined However social norms canand do change and this process can be aided bythe coordinated efforts of civil society healthorganizations and government as has beenobserved in the case of smoking cessationThere are growing calls for government to

intervene with changes to economic politicalandor legal systems that could transform thesystem of meat production supply and distribu-tion (74) It is uncontroversial that governmentsshould act to prevent chemically or biologicallycontaminated food from reaching markets In-deed some ancient religious prohibitions oneating certain types of meat may have arisen toreduce food poisoning (75) There is more con-troversy over the degree to which the state shoulduse animal welfare (or other) considerations tolimit the production and sale of certain types ofmeat There are technical and philosophical chal-lenges in assessing an animalrsquos quality of lifecomplicated by the fact that often livestock breedsare the results of many generations of selectionfor economically important traits that may leadto correlated effects on welfare (76) States also

Godfray et al Science 361 eaam5324 (2018) 20 July 2018 5 of 8

Fig 5 The dual-process model of motivation and interventions that target automatic anddeliberative decision-making Examples of (i) situational factors are events moods andemotions (ii) the environment are the layout of products in a shop or the marketing experiencedby an individual and (iii) personal characteristics are factors such as values beliefs and traitssuch as self-restraint or impulsivity

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nloaded from

intervene to protect certain wild animals frombeing hunted for food which is often a conten-tious issuemdashfor example where consumption ofldquobushmeatrdquo is culturally engrained All developedand many developing countries have legislationthat prohibits the production and sale of certaintypes of meat based on noneconomic animalrights or conservation considerations but thereis no consensus on their strictnessA further consideration is the tension between

state-sponsored interventions in the food systemand free trade Under World Trade Organizationrules and embodied in most trade agreementsgovernments are allowed to restrict meat im-ports for reasons of food safety as well as toprotect local farming from exogenous livestockdisease What is not allowed is for protectionisttariffs to be imposed using these reasons as anexcuse For example Samoa was forced to re-verse a ban on fatty-meat imports introducedas an anti-obesity measure (77) Current debatesabout whether chlorine-washed poultry could inthe future be imported into the European Union(EU) illustrate these complexities (78) This proce-dure is currently banned in the EU which has adifferent philosophy for ensuring the microbialsafety of food emphasizing interventions earlierin the food chainChanging the behavior of populations to re-

duce the demand for meat can be usefully con-sidered through the lens of dual-process theory(Fig 5) which considers the role of both con-scious and nonconscious processes operatingin parallel to influence food selection (19) Al-though there is little direct evidence of theeffectiveness of interventions to reduce demandfor meat there is a body of potentially relevantwork that might inform how this could beimplemented One strand of potential inter-ventions operates within the rational choiceparadigm based on reflective conscious process-ing For example nutritional labeling is used toenable people to make healthier dietary choices(79) although there is little evidence that labelsfocused on sustainability criteria change behavior(80) Certification programs run by the privatesector or nongovernmental organizations areanother means of providing trusted evidenceabout welfare or environmental standards Al-though such interventions are likely to havemodest impact in themselves the lesson oftobacco control is that raising awareness ofimplications for health has been crucial ingarnering support for policy changes (81)Attempts to change diets through fiscal inter-

ventions also lies within a rational choice frame-work Although not specifically aimed at meatconsumption (andmotivatedmore by economicsthan health) Denmark operated a tax on thesaturated fat content of foods between 2011 and2012 that raised prices of somemeat products by15 (82) Since its repeal analyses of panel datahave shown that the tax accompanied reductionsin consumption of products high in saturatedfat including minced beef (83) and modelingof long-term health outcomes suggests a reduc-tion in noncommunicable disease and premature

mortality (84) Theoretical work has exploredtaxing food types in proportion to their GHGemissions (85ndash87) In these scenarios as meatprices rise substantial health and environmentbenefits are predicted to accrue especially ifsupplementarymeasures are introduced to avoidnegative effects for those on low incomes (Fig 1C)Some interventions depend on unconscious

behavioral processes for their effectiveness andare largely automatic responses to environmentalcues with the result that people tend automati-cally to take a default option rather than activelyseek out an ldquoopt-inrdquo alternative For examplethere is some evidence that repositioning meatoptions to appear after rather than before veg-etarian options on menus or in buffets to makethese items more prominent may increase thenumber of people selecting meat-free mealsbut more research is needed (88) Decreasingportion size of meat products in a restauranthas been shown to decrease meat consumptionwith no detrimental impact on customersrsquo per-ception of their restaurant experience perhapsbecause the meat is a small part of the overallevent (89) These approaches nudge consumersinto changing their behavior without necessar-ily requiring a conscious ldquochoicerdquo Behaviorallymotivated interventions are seen in some politicalphilosophies as preferable to interventions in themarket (90) Others worry about their effective-ness and the ethics of trying to manipulate pop-ulation behavior (91)Concerns about the ethics and environmental

consequences of meat consumption have led to arapid expansion in the development of meatsubstitutes Substantial new investment is goinginto products based on legumes and other plantsand novel substitutes based on a variety of mi-crobial and plant substrates are attracting sub-stantial venture capital (92) Not as advancedbut also receiving substantial attention iscultured meat developed in the light of re-cent advances in our understanding of muscledevelopment (93) A new research challenge isto understand the consumer response to thesefoods and to assess the economic labor environ-mental and health consequences were they to beproduced at large scale

Conclusions

Future changes in global meat consumptionwill have major effects on the environment andhuman health as well as on the economics of thefood system It is difficult to envisage how theworld could supply a population of 10 billion ormore people with the quantity of meat currentlyconsumed in most high-income countries with-out substantial negative effects on environmentalsustainability Current evidence suggests thatincreased consumption of meat especially redand processed meats will adversely affect publichealth There are data suggesting that in somehigh-income countries per capita meat consump-tion is plateauing or beginning to decline and thatldquopeakmeatrdquomayhave passed But consumption isincreasing in many other countries includingthose with large populations such as China

There is need for more evidence about theeffectiveness of different interventions seeking toaffect peoplersquos conscious and unconscious foodpurchasing and consumption practices This willrequire a better understanding of how individualactions are influenced by societal norms and thestructure of the food system within which in-dividuals are embedded The multitude of fac-tors that influence the price and availability ofmeat and how it is processed and marketeddetermine a socioeconomic landscape that pro-foundly affects and is affected by norms andbehaviors The existence of major vested interestsand centers of powermakes the political economyof diet change highly challengingHistory suggests that change in dietary be-

haviors in response to interventions is slow Butsocial norms can and do change and this processcan be aided by the coordinated efforts of civilsociety health organizations and governmentHowever it is likely to require a good understand-ing of the impact of meat consumption on healthand the environment and a license from societyfor a suite of interventions to stimulate change

REFERENCES AND NOTES

1 FAO FAOSTAT (2018) wwwfaoorgfaostatendata2 M H Forouzanfar et al Global regional and national

comparative risk assessment of 79 behavioural environmentaland occupational and metabolic risks or clusters of risksin 188 countries 1990-2013 A systematic analysis forthe Global Burden of Disease Study 2013 Lancet 3862287ndash2323 (2015) doi 101016S0140-6736(15)00128-2pmid 26364544

3 N Ramankutty J A Foley Estimating historical changes inglobal land cover Croplands from 1700 to 1992 GlobalBiogeochem Cycles 13 997ndash1027 (1999) doi 1010291999GB900046

4 M M Mekonnen A Y Hoekstra A global assessment of thewater footprint of farm animal products Ecosystems (N Y) 15401ndash415 (2012) doi 101007s10021-011-9517-8

5 Organisation for Economic Co-operation and Development(OECD) FAO Agricultural Outlook 2015 (OECD Publishing 2015)

6 W Willett Nutritional epidemiology (Oxford Univ Press 2012)7 FAO Food Balance Sheets a Handbook (FAO Rome 2001)8 J Gustavsson C Cederberg U Sonesson R van Otterdijk

A Meybeck Global Food Losses and Food Waste (FAO 2011)9 V Bouvard et al Carcinogenicity of consumption of red and

processed meat Lancet Oncol 16 1599ndash1600 (2015)doi 101016S1470-2045(15)00444-1 pmid 26514947

10 M C Rufino et al Transitions in agro-pastoralist systems ofEast Africa Impacts on food security and povertyAgric Ecosyst Environ 179 215ndash230 (2013) doi 101016jagee201308019

11 R Micha et al Global regional and national consumption ofmajor food groups in 1990 and 2010 A systematic analysisincluding 266 country-specific nutrition surveys worldwideBMJ Open 5 e008705 (2015) doi 101136bmjopen-2015-008705 pmid 26408285

12 M K Bennett Wheat in national diets Food Res Inst Stud 1837ndash76 (1941)

13 B M Popkin The nutrition transition and its healthimplications in lower-income countries Public Health Nutr 15ndash21 (1998) doi 101079PHN19980004 pmid 10555527

14 D Tilman C Balzer J Hill B L Befort Global fooddemand and the sustainable intensification of agricultureProc Natl Acad Sci USA 108 20260ndash20264 (2011)doi 101073pnas1116437108 pmid 22106295

15 H Valin et al The future of food demand Understandingdifferences in global economic models Agric Econ-Blackwell45 51ndash67 (2014) doi 101111agec12089

16 N Alexandratos J Bruinsma World Agriculture Towards 20302050 The 2012 Revision ESA Working paper No 12-03 (FAO 2012)

17 A Drewnowski J A Mennella S L Johnson F BellisleSweetness and food preference J Nutr 142 1142Sndash1148S(2012) doi 103945jn111149575 pmid 22573785

Godfray et al Science 361 eaam5324 (2018) 20 July 2018 6 of 8

RESEARCH | REVIEW

Corrected 12 December 2018 See full text on January 27 2020

httpsciencesciencemagorg

Dow

nloaded from

18 K C Berridge C Y Ho J M Richard A G DiFeliceantonioThe tempted brain eats Pleasure and desire circuits in obesityand eating disorders Brain Res 1350 43ndash64 (2010)doi 101016jbrainres201004003 pmid 20388498

19 T M Marteau Towards environmentally sustainable humanbehaviour Targeting non-conscious and conscious processesfor effective and acceptable policies Philos Trans A MathPhys Eng Sci 375 20160371 (2017) doi 101098rsta20160371 pmid 28461435

20 M Nestle Food Politics How the Food Industry InfluencesNutrition and Health (Revised Edition) (Univ California Press2007)

21 N D Barnard W C Willett E L Ding The misuse ofmeta-analysis in nutrition research JAMA 318 1435ndash1436(2017) doi 101001jama201712083 pmid 28975260

22 M J Orlich et al Vegetarian dietary patterns and mortality inAdventist Health Study 2 JAMA Intern Med 173 1230ndash1238(2013) doi 101001jamainternmed20136473pmid 23836264

23 P N Appleby F L Crowe K E Bradbury R C TravisT J Key Mortality in vegetarians and comparablenonvegetarians in the United Kingdom Am J Clin Nutr 103218ndash230 (2016) doi 103945ajcn115119461pmid 26657045

24 D K Dror L H Allen The importance of milk and otheranimal-source foods for children in low-income countriesFood Nutr Bull 32 227ndash243 (2011) doi 101177156482651103200307 pmid 22073797

25 J Jackson R Williams M McEvoy L MacDonald-WicksA Patterson Is higher consumption of animal flesh foodsassociated with better iron status among adults in developedcountries A systematic review Nutrients 8 89 (2016)doi 103390nu8020089 pmid 26891320

26 K Shridhar et al The association between a vegetarian dietand cardiovascular disease (CVD) risk factors in IndiaThe Indian Migration Study PLOS ONE 9 e110586 (2014)doi 101371journalpone0110586 pmid 25343719

27 S Rohrmann et al Meat consumption and mortalitymdashResultsfrom the European Prospective Investigation into Cancerand Nutrition BMC Med 11 63 (2013) doi 1011861741-7015-11-63 pmid 23497300

28 A Etemadi et al Mortality from different causes associatedwith meat heme iron nitrates and nitrites in the NIH-AARPDiet and Health Study Population based cohort study BMJ357 j1957 (2017) doi 101136bmjj1957 pmid 28487287

29 R Sinha A J Cross B I Graubard M F LeitzmannA Schatzkin Meat intake and mortality A prospective study ofover half a million people Arch Intern Med 169 562ndash571(2009) doi 101001archinternmed20096 pmid 19307518

30 X Wang et al Red and processed meat consumption andmortality Dose-response meta-analysis of prospective cohortstudies Public Health Nutr 19 893ndash905 (2016) doi 101017S1368980015002062 pmid 26143683

31 IARC ldquoQ amp A on the carcinogenicity of the consumptionof red meat and processed meatrdquo (World Health Organization2015)

32 World Cancer Research Fund (WCRF) ldquoAnimal foodsrdquo(World Cancer Research Fund 2017)

33 A Wolk Potential health hazards of eating red meatJ Intern Med 281 106ndash122 (2017) doi 101111joim12543pmid 27597529

34 A C Vergnaud et al Meat consumption and prospectiveweight change in participants of the EPIC-PANACEA studyAm J Clin Nutr 92 398ndash407 (2010) doi 103945ajcn200928713 pmid 20592131

35 J E Lee et al Meat intake and cause-specific mortalityA pooled analysis of Asian prospective cohort studiesAm J Clin Nutr 98 1032ndash1041 (2013) doi 103945ajcn113062638 pmid 23902788

36 M S Farvid et al Dietary protein sources and all-cause andcause-specific mortality The Golestan Cohort Study in IranAm J Prev Med 52 237ndash248 (2017) doi 101016jamepre201610041 pmid 28109460

37 Z Wang et al Gut flora metabolism of phosphatidylcholinepromotes cardiovascular disease Nature 472 57ndash63 (2011)doi 101038nature09922 pmid 21475195

38 A M Bernstein et al Major dietary protein sources and risk ofcoronary heart disease in women Circulation 122 876ndash883(2010) doi 101161CIRCULATIONAHA109915165 pmid20713902

39 A M Bernstein et al Dietary protein sources and the risk ofstroke in men and women Stroke 43 637ndash644 (2012)doi 101161STROKEAHA111633404 pmid 22207512

40 A Pan et al Red meat consumption and risk of type 2diabetes 3 cohorts of US adults and an updatedmeta-analysis Am J Clin Nutr 94 1088ndash1096 (2011)doi 103945ajcn111018978 pmid 21831992

41 A Pan et al Red meat consumption and mortalityResults from 2 prospective cohort studies Arch Intern Med172 555ndash563 (2012) doi 101001archinternmed20112287pmid 22412075

42 M Song et al Association of animal and plant proteinintake with all-cause and cause-specific mortality JAMAIntern Med 176 1453ndash1463 (2016) doi 101001jamainternmed20164182 pmid 27479196

43 M Springmann H C J Godfray M Rayner P ScarboroughAnalysis and valuation of the health and climate changecobenefits of dietary change Proc Natl Acad Sci USA113 4146ndash4151 (2016) doi 101073pnas1523119113pmid 27001851

44 WCRF ldquoContinuous Update Project (October 2017)rdquo(WCRF 2017)

45 P Williams P Brent in Essentials of Human Nutrition J MannA S Truswell Eds (Oxford Univ Press 2017) pp 316ndash336

46 M Greger The humananimal interface Emergence andresurgence of zoonotic infectious diseases Crit Rev Microbiol33 243ndash299 (2007) doi 10108010408410701647594pmid 18033595

47 B A Jones et al Zoonosis emergence linked to agriculturalintensification and environmental change Proc Natl Acad SciUSA 110 8399ndash8404 (2013) doi 101073pnas1208059110pmid 23671097

48 T P Van Boeckel et al Global trends in antimicrobialuse in food animals Proc Natl Acad Sci USA 1125649ndash5654 (2015) doi 101073pnas1503141112pmid 25792457

49 L Aleksandrowicz R Green E J Joy P Smith A HainesThe impacts of dietary change on greenhouse gas emissionsland use water use and health A systematic reviewPLOS ONE 11 e0165797 (2016) doi 101371journalpone0165797 pmid 27812156

50 D Tilman M Clark Global diets link environmentalsustainability and human health Nature 515 518ndash522 (2014)doi 101038nature13959 pmid 25383533

51 P J Gerber et al ldquoTackling climate change through livestocka global assessment of emissions and mitigationopportunitiesrdquo (FAO 2013)

52 FAO ldquoLivestockrsquos Long Shadowrdquo (FAO 2006)53 M Herrero et al Livestock and greenhouse gas emissions

The importance of getting the numbers right Anim FeedSci Technol 166-167 779ndash782 (2011) doi 101016janifeedsci201104083

54 R T Pierrehumbert G Eshel Climate impact of beefAn analysis considering multiple time scales and productionmethods without use of global warming potentialsEnviron Res Lett 10 085002 (2015) doi 1010881748-9326108085002

55 M Herrero et al Biomass use production feed efficienciesand greenhouse gas emissions from global livestock systemsProc Natl Acad Sci USA 110 20888ndash20893 (2013)doi 101073pnas1308149110 pmid 24344273

56 B B Henderson et al Greenhouse gas mitigation potential ofthe worldrsquos grazing lands Modeling soil carbon and nitrogenfluxes of mitigation practices Agric Ecosyst Environ 20791ndash100 (2015) doi 101016jagee201503029

57 Savory Institute ldquoRestoring the climate through capture andstorage of soil carbon through holistic planned grazingrdquo(Savory Institute 2013)

58 R T Conant C E P Cerri B B Osborne K PaustianGrassland management impacts on soil carbon stocks A newsynthesis Ecol Appl 27 662ndash668 (2017) doi 101002eap1473 pmid 27875004

59 D D Briske A J Ash J D Derner L HuntsingerCommentary A critical assessment of the policy endorsementfor holistic management Agric Syst 125 50ndash53 (2014)doi 101016jagsy201312001

60 T Garnett et al ldquoGrazed and confusedrdquo (Food ClimateResearch Network 2017)

61 A Y Hoekstra M M Mekonnen The water footprint ofhumanity Proc Natl Acad Sci USA 109 3232ndash3237 (2012)doi 101073pnas1109936109 pmid 22331890

62 D R Steward et al Tapping unsustainable groundwaterstores for agricultural production in the High Plains Aquifer ofKansas projections to 2110 Proc Natl Acad Sci USA110 E3477ndashE3486 (2013) doi 101073pnas1220351110pmid 23980153

63 G Eshel A Shepon T Makov R Milo Land irrigationwater greenhouse gas and reactive nitrogen burdens of meateggs and dairy production in the United States Proc NatlAcad Sci USA 111 11996ndash12001 (2014) doi 101073pnas1402183111 pmid 25049416

64 M H Ward et al Workgroup report Drinking-water nitrate andhealthmdashRecent findings and research needs Environ HealthPerspect 113 1607ndash1614 (2005) doi 101289ehp8043pmid 16263519

65 D Tilman K G Cassman P A Matson R Naylor S PolaskyAgricultural sustainability and intensive productionpractices Nature 418 671ndash677 (2002) doi 101038nature01014 pmid 12167873

66 V Novotny Diffuse pollution from agriculturemdashA worldwideoutlook Water Sci Technol 39 1ndash13 (1999) doi 102166wst19990124

67 V De Sy et al Land use patterns and related carbon lossesfollowing deforestation in South America Environ Res Lett 10124004 (2015) doi 1010881748-93261012124004

68 J Graesser T M Aide H R Grau N Ramankutty Croplandpastureland dynamics and the slowdown of deforestationin Latin America Environ Res Lett 10 034017 (2015)doi 1010881748-9326103034017

69 N Crawhall et al ldquoConserving dryland biodiversityrdquo(International Union for Conservation of Nature 2012)

70 S D Fuhlendorf D M Engle Restoring heterogeneity onrangelands Ecosystem management based on evolutionarygrazing patterns Bioscience 51 625ndash632 (2001) doi 1016410006-3568(2001)051[0625RHOREM]20CO2

71 T T Sylvester et al Prevalence and risk factors forMycobacterium bovis infection in african lions (Panthera leo)in the Kruger National Park J Wildl Dis 53 372ndash376 (2017)doi 1075892016-07-159 pmid 28122192

72 D Normile Driven to extinction Science 319 1606ndash1609(2008) doi 101126science31958701606 pmid 18356500

73 J Piazza et al Rationalizing meat consumption The 4NsAppetite 91 114ndash128 (2015) doi 101016jappet201504011pmid 25865663

74 L Wellesley A Froggatt C Happer ldquoChanging ClimateChanging Diets Pathways to Lower Meat Consumptionrdquo(Chatham House 2015)

75 V B Meyer-Rochow Food taboos Their origins and purposesJ Ethnobiol Ethnomed 5 18 (2009) doi 1011861746-4269-5-18 pmid 19563636

76 M S Dawkins Why Animals Matter (Oxford Univ Press 2011)77 W Snowdon A M Thow Trade policy and obesity

prevention Challenges and innovation in the Pacific IslandsObes Rev 14 (Suppl 2) 150ndash158 (2013) doi 101111obr12090 pmid 24102909

78 E Millstone T Lang T Marsden ldquoWill the British public acceptchlorine-washed turkey for Christmas dinner after Brexitrdquo(Food Research Collaboration 2017)

79 R A Crockett et al Nutritional labelling for healthier food ornon-alcoholic drink purchasing and consumption CochraneDatabase Syst Rev 2 CD009315 (2018) pmid 29482264

80 K G Grunert S Hieke J Wills Sustainability labels on foodproducts Consumer motivation understanding and useFood Policy 44 177ndash189 (2014) doi 101016jfoodpol201312001

81 Royal College of Physicians ldquoFifty years since Smokingand health Progress lessons and priorities for a smoke-freeUKrdquo (Royal College of Physicians 2012)

82 S Vallgaringrda L Holm J D Jensen The Danish tax onsaturated fat Why it did not survive Eur J Clin Nutr 69223ndash226 (2015) doi 101038ejcn2014224 pmid 25351647

83 J D Jensen S Smed L Aarup E Nielsen Effects of theDanish saturated fat tax on the demand for meat and dairyproducts Public Health Nutr 19 3085ndash3094 (2016)doi 101017S1368980015002360 pmid 26306542

84 S Smed P Scarborough M Rayner J D Jensen The effectsof the Danish saturated fat tax on food and nutrient intake andmodelled health outcomes An econometric and comparativerisk assessment evaluation Eur J Clin Nutr 70 681ndash686(2016) doi 101038ejcn20166 pmid 27071513

85 M Springmann et al Mitigation potential and global healthimpacts from emissions pricing of food commoditiesNat Clim Chang 7 69ndash74 (2016) doi 101038nclimate3155

86 A Kehlbacher R Tiffin A Briggs M Berners-LeeP Scarborough The distributional and nutritional impactsand mitigation potential of emission-based food taxesin the UK Clim Change 137 121ndash141 (2016) doi 101007s10584-016-1673-6

Godfray et al Science 361 eaam5324 (2018) 20 July 2018 7 of 8

RESEARCH | REVIEW

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87 A D M Briggs A Kehlbacher R Tiffin P ScarboroughSimulating the impact on health of internalising the cost ofcarbon in food prices combined with a tax on sugar-sweetenedbeverages BMC Public Health 16 107 (2016) doi 101186s12889-016-2723-8 pmid 26837190

88 V Campbell-Arvai Food-related environmental beliefsand behaviours among university undergraduatesA mixed-methods study Int J Sustain High Educ 16279ndash295 (2015) doi 101108IJSHE-06-2013-0071

89 M J Reinders M Huitink S C Dijkstra A J MaaskantJ Heijnen Menu-engineering in restaurantsmdashAdaptingportion sizes on plates to enhance vegetableconsumption A real-life experiment Int J BehavNutr Phys 14 41 (2017) doi 101186s12966-017-0496-9pmid 28424081

90 R H Thaler C R Sunstein Libertarian paternalismAm Econ Rev 93 175ndash179 (2003) doi 101257000282803321947001

91 D M Hausman B Welch Debate To nudge or not to nudgeJ Polit Philos 18 123ndash136 (2010) doi 101111j1467-9760200900351x

92 The Economist Silicon Valley gets a taste for food (2015)wwweconomistcomnewstechnology-quarterly21645497-tech-startups-are-moving-food-business-make-sustainable-versions-meat

93 M J Post Cultured meat from stem cells Challenges andprospects Meat Sci 92 297ndash301 (2012) doi 101016jmeatsci201204008 pmid 22543115

94 M Springmann et al Global and regional health effects offuture food production under climate change A modellingstudy Lancet 387 1937ndash1946 (2016) doi 101016S0140-6736(15)01156-3 pmid 26947322

95 T Norat et al Meat fish and colorectal cancer risk TheEuropean Prospective Investigation into cancer and nutritionJ Natl Cancer Inst 97 906ndash916 (2005) doi 101093jncidji164 pmid 15956652

96 J OrsquoNeill Antimicrobials in Agriculture and the EnvironmentReducing Unnecessary Use and Waste (Welcome Trust and HMGovernment 2015)

97 M N Macedo et al Decoupling of deforestationand soy production in the southern Amazon duringthe late 2000s Proc Natl Acad Sci USA 109

1341ndash1346 (2012) doi 101073pnas1111374109pmid 22232692

ACKNOWLEDGMENTS

We are grateful to F Bianchi A Stephens and L Walkerfor assistance in preparing the review Funding Thiswork was supported by the Wellcome Trustrsquos Our PlanetOur Health program (205212Z16Z) PA was funded by theNIHR Oxford Biomedical Research Centre The views expressedare those of the authors and not necessarily those of the NHSthe NIHR or the Department of Health and Social CareCompeting interests MS declares consultancy fees by theEAT Foundation for a background report for the EAT-LancetCommission on Healthy Diets from Sustainable Food Systemsand consultancy fees from the Global Panel on Agricultureand Food Systems for Nutrition (GLOPAN) for a backgroundpaper on food systems All other authors declare nocompeting interests

101126scienceaam5324

Godfray et al Science 361 eaam5324 (2018) 20 July 2018 8 of 8

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Meat consumption health and the environment

Scarborough Marco Springmann and Susan A JebbH Charles J Godfray Paul Aveyard Tara Garnett Jim W Hall Timothy J Key Jamie Lorimer Ray T Pierrehumbert Peter

DOI 101126scienceaam5324 (6399) eaam5324361Science

this issue p eaam5324Sciencethe complex social factors associated with meat eating and developing policies for effective interventionscolorectal cancer and cardiovascular disease Changing meat consumption habits is a challenge that requires identifying a concentrated source of nutrients for low-income families it also enhances the risks of chronic ill health such as fromthis trend which has major negative consequences for land and water use and environmental change Although meat is

reviewet alMeat consumption is rising annually as human populations grow and affluence increases Godfray The future of meat

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REFERENCES

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is a registered trademark of AAASScienceScience 1200 New York Avenue NW Washington DC 20005 The title (print ISSN 0036-8075 online ISSN 1095-9203) is published by the American Association for the Advancement ofScience

Science No claim to original US Government WorksCopyright copy 2018 The Authors some rights reserved exclusive licensee American Association for the Advancement of

on January 27 2020

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