Sci­en­tists’ diet to save the world

What we eat has an im­pact on the global warm­ing and a re­port says we need to change our ways, writes

The Northern Advocate - - World - Joel Achenbach

The hu­man pop­u­la­tion has reached 7.6 bil­lion and could num­ber 9 bil­lion or 10 bil­lion by mid-cen­tury. All those peo­ple will need to eat.

A sober­ing re­port pub­lished on Thurs­day in the jour­nal Na­ture ar­gues that a sus­tain­able food sys­tem that doesn’t rav­age the en­vi­ron­ment is go­ing to re­quire dra­matic re­forms — in­clud­ing a rad­i­cal change in di­etary habits.

To be spe­cific: Cheese­burg­ers are out, fruits and veg­gies are in.

The 23 au­thors of the re­port — hail­ing from Europe, the United States, Aus­tralia and Lebanon — re­viewed the many mov­ing parts of the global food sys­tem and how they in­ter­act with the en­vi­ron­ment. The au­thors con­cluded that cur­rent meth­ods of pro­duc­ing, dis­tribut­ing and con­sum­ing food are not en­vi­ron­men­tally sus­tain­able, and that dam­age to the planet could make it less hos­pitable for hu­man ex­is­tence.

A core mes­sage from the re­searchers is that ef­forts to keep cli­mate change at an ac­cept­able level will not be suc­cess­ful with­out a huge re­duc­tion in meat con­sump­tion.

“Feed­ing hu­man­ity is pos­si­ble. It’s just a ques­tion of whether we can do it in an en­vi­ron­men­tally re­spon­si­ble way,” said Jo­han Rock­strom, an earth sci­en­tist at the Pots­dam In­sti­tute for Cli­mate Im­pact Re­search in Ger­many and a co-au­thor of the study.

The re­port comes on the heels of a warn­ing from the United Na­tions In­ter­gov­ern­men­tal Panel on Cli­mate Change that global lead­ers need to take un­prece­dented ac­tion in the next decade to keep the planet’s aver­age tem­per­a­ture from ris­ing more than 1.5C above prein­dus­trial lev­els.

Global warm­ing has typ­i­cally been linked to the burn­ing of fos­sil fu­els, but food pro­duc­tion is a huge and un­der­ap­pre­ci­ated fac­tor, and the new re­port seeks to place food in the cen­tre of the con­ver­sa­tion about how hu­man­ity can cre­ate a sus­tain­able fu­ture.

“Ev­ery­body knows that en­ergy has some­thing to do with cli­mate — we need to trans­form our en­ergy sys­tem. There’s very few peo­ple who re­alise that it’s just as, and maybe more, im­por­tant to trans­form our food sys­tem,” said Kather­ine Richard­son, di­rec­tor of the Sus­tain­able Sci­ence Cen­tre at the Uni­ver­sity of Copen­hagen in Den­mark. Richard­son, who was not part of the team pro­duc­ing the new study, added, “The food sys­tem is bro­ken and needs to be fixed if we have any hope of feed­ing 9 to 10 bil­lion.”

Al­ready, half the planet’s ice­free land sur­face is de­voted to live­stock or the grow­ing of feed for those an­i­mals, Richard­son said. That’s an area equal to North and South Amer­ica com­bined, she said. Rain forests are steadily be­ing cleared for crop­land.

And the de­mand for food is in­creas­ing faster than the pop­u­la­tion: Ris­ing in­come in China and many other for­merly im­pov­er­ished coun­tries brings with it a higher de­mand for meat and other forms of an­i­mal pro­tein.

Some 70 per cent of the world’s fresh wa­ter is al­ready used in agri­cul­ture, and the de­mand for that wa­ter will in­ten­sify.

The Na­ture re­port, ti­tled Op­tions for keep­ing the food sys­tem within en­vi­ron­men­tal lim­its, con­tends that, with­out tar­geted changes, pres­sures on var­i­ous en­vi­ron­men­tal sys­tems will in­crease 50 to 90 per cent by 2050 com­pared with 2010. There’s no sim­ple so­lu­tion, the au­thors write. Rather, “a syn­er­gis­tic com­bi­na­tion of mea­sures” will be needed to limit the en­vi­ron­men­tal dam­age.

One ob­vi­ous mea­sure is a change in di­ets. Re­searchers say meat pro­duc­tion — which in­cludes grow­ing food specif­i­cally to feed to live­stock — is an en­vi­ron­men­tally in­ef­fi­cient way to gen­er­ate calo­ries for hu­man con­sump­tion. More­over, ru­mi­nants such as cows are prodi­gious pro­duc­ers of meth­ane as they di­gest food, and meth­ane is a po­tent green­house gas. The re­port says green­house­gas emis­sions from the global food sys­tem could be re­duced sig­nif­i­cantly if peo­ple curb red-meat con­sump- tion and fol­low a diet built around fruits, veg­eta­bles, nuts and legumes.

To limit green­house-gas emis­sions, “We won’t get very far if we don’t se­ri­ously think about di­etary changes to a more plant­based diet,” said Marco Spring­mann, lead au­thor of the re­port and a se­nior re­searcher at the Ox­ford Martin Pro­gramme on the Fu­ture of Food.

He said that what is good for the planet is good for the eater. For most peo­ple con­sum­ing a typ­i­cal Western diet, eat­ing less meat will gen­er­ally mean bet­ter health.

Two rep­re­sen­ta­tives of the Na­tional Cat­tle­men’s Beef As­so­ci­a­tion, asked to re­spond to the Na­ture re­port, said the US beef in­dus­try was fo­cused on

im­prov­ing the ef­fi­ciency of beef pro­duc­tion.

The United States had 128 mil­lion head of cat­tle (in­clud­ing dairy cows) in 1976 and 94 mil­lion cat­tle as of this past Jan­uary, yet it pro­duces just as much beef to­day as it did in the 1970s, in part be­cause of breed­ing ef­forts that boosted the growth rate of the live­stock, said Sara Place, the Beef As­so­ci­a­tion’s se­nior di­rec­tor for re­search on sus­tain­able beef pro­duc­tion.

New Zealand had 10 mil­lion cat­tle (6.5 mil­lion for dairy) in 2015, ac­cord­ing to gov­ern­ment fig­ures.

The re­port notes that the cur­rent food sys­tem is in­cred­i­bly waste­ful, with about one-third of the food pro­duced even­tu­ally be­ing dis­carded. Most of that food waste comes from spoilage. Halv­ing the amount of wasted food would put a dent in the over­all en­vi­ron­men­tal prob­lem, they said, and re­duc­ing waste by 75 per cent is the­o­ret­i­cally pos­si­ble.

The re­port is ag­nos­tic on whether the world should adopt ge­net­i­cally mod­i­fied or­gan­isms (GMOs) in the food sup­ply.

The re­port also does not take a po­si­tion on pop­u­la­tion

growth. Al­though birth rates have de­clined dra­mat­i­cally in many coun­tries — to lev­els far be­low the re­place­ment rate — the global pop­u­la­tion con­tin­ues to rise. A 2015 UN re­port es­ti­mated that the pop­u­la­tion would reach 9.7 bil­lion by 2050.

Decades ago, the prospect of so many hu­man be­ings crowd­ing the planet in­spired pre­dic­tions of widespread famine. The “green rev­o­lu­tion” in agri­cul­ture changed the equa­tions.

Still, the food is not evenly dis­trib­uted.

About 3 bil­lion peo­ple are mal­nour­ished to­day and 1 bil­lion of them suf­fer from food scarcity, ac­cord­ing to Rock­strom.

At the core of this re­search is the ar­gu­ment that Earth has sev­eral lim­its, the “plan­e­tary bound­aries”, that can­not be ex­ceeded with­out po­ten­tially dire con­se­quences. These bound­aries — which in­volve fac­tors such as cli­mate change, loss of bio­di­ver­sity, de­for­esta­tion, at­mo­spheric aerosols (smog), strato­sphere-ozone de­ple­tion and the sup­ply of fresh wa­ter — de­fine the “safe op­er­at­ing space” for hu­man­ity.

Pro­po­nents of the hy­poth­e­sis say that hu­man civil­i­sa­tion has thrived in the ge­o­log­i­cal epoch known as the Holocene, cov­er­ing a pe­riod of roughly 11,700 years since the end of the last ice age, but that dam­age to the en­vi­ron­ment could put hu­man­ity into an ex­is­ten­tial cri­sis.

“You can imag­ine a sce­nario in which con­tem­po­rary so­ci­ety starts to un­ravel” be­cause of degra­da­tion in the en­vi­ron­ment, said Will Stef­fen, an emer­i­tus pro­fes­sor of Earth-sys­tem sci­ence at the Aus­tralian Na­tional Uni­ver­sity and a pro­po­nent of the plan­e­tary-bound­aries hy­poth­e­sis.

“So it’s a long fuse, big bang.” He noted a move­ment in Aus­tralia to pro­mote the con­sump­tion of kan­ga­roo meat, since kan­ga­roos are not ru­mi­nants and don’t have the same eco­log­i­cal foot­print.

“It’s a gamier taste, but it’s also a much leaner meat. It takes more tal­ent to cook it to make it easy to chew and di­gest,” he said, be­fore quickly adding, “I don’t like the thought of the poor lit­tle guys get­ting shot.”

We won’t get very far if we don’t se­ri­ously think about di­etary changes to a more plant-based diet. Marco Spring­mann, Ox­ford Martin Pro­gramme on the Fu­ture of Food

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