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Science Magazine considers whether decreasing meat consumption can increase global food security

Saturday, February 13th, 2010


In this week’s special issue devoted to food security, Science asks what it will take to feed 9 billion people by mid century.

Food insecurity—the inability of people to feed themselves—may rise if food supply cannot keep pace with population.  This is a concern that goes back over 200 years to Thomas Malthus.

One theme shows up in a few articles:  Can reducing meat consumption help in the battle to feed more people?

Erik Stokstad’s news feature (subscription required)1 provides a nice lead:

The United States, for instance, has just 4.5% of the world’s population but accounts for about 15% of global meat consumption. Americans consume about 330 grams of meat a day on average—the equivalent of three quarter-pound hamburgers. In contrast, the U.S. Department of Agriculture recommends that most people consume just 142 to 184 grams of meat and beans daily. In the developing world, daily meat consumption averages just 80 grams. Those numbers suggest that people living in the United States and other wealthy nations could increase world grain supplies simply by forgoing that extra burger or chop.

However, he interviews researchers and cites studies that raise a number of issues potentially complicating this story…

  • As meat consumption in developed nations decreases, the price of meat should decrease and become more affordable to people in the developing world, which could actually cause increased demand and meat consumption to rise globally by 13%.
  • A study by the International Food Policy Research Institute’s Mark Rosegrant suggests that grain consumption would only rise slightly in the developing world.  As Stokstad reports,

Surprisingly, however, when the rich halved their meat habit, the poor didn’t necessarily get that much more grain—their largest source of calories. According to the model, per capita cereal consumption in developing nations rose by just 1.5%. That’s enough grain to ease hunger for 3.6 million malnourished children—but nowhere near the kinds of gains many expect from curbing meat consumption.

Stokstad argues the reason for this is a mismatch in grain fed to cattle vs. people.  In the developed world, for instance, farmers feed soybeans and corn to livestock, whereas people in developing nations in Asia eat more rice and wheat.  The gains in soybeans and corn therefore don’t necessarily translate into more food for people.

  • When developed nations replace meat with pasta and bread, wheat prices worldwide rise, possibly threatening food insecurity to Asians who might no longer be able to afford the higher costs of wheat.

Following these assessments, Stokstad suggests

When all the pluses and minuses are added up, Rosegrant is confident that cutting meat consumption could ultimately help improve global food security. But “it’s a small contribution, like changing to fluorescent light bulbs” to fight global warming, he says.

While it’s important to consider unexpected twists and surprises, I’m not completely convinced by these arguments for a number of reasons, many of which Stokstad offers as caveats to the above assessment:

  • As another review article by Charles Godfray et al.2 in the same Science issue notes, about one third of the global supply of grain is fed to livestock.  That’s A LOT of food energy.  If you consider that you can feed many more people on a hectare of grain crops than livestock,  that’s a significant boost in food energy to the world, especially if the developed world cuts meat consumption significantly further than the 50% reduction Rosegrant assumes.   Some might argue that this is impractical—the world would never go vegetarian en masse.  Maybe so.  However, if the question is can we feed significantly more people by reducing meat consumption, the answer is clearly yes.  Whether we actually chose to reduce meat consumption enough is another (normative) question.
  • As Stokstad notes, in many regions of the developing world, like Latin America and Africa, corn is a dietary staple, so diverting these grains from livestock to people will add more crops to the global markets and drop prices, encouraging greater consumption by a sizable fraction of the developing world.
  • What about Asians, who eat more rice and wheat?  Stokstad seems to believe that crop substitutions are unlikely:

It’s true that as demand for corn drops, some farmers might start growing wheat instead. In general, however, climate, soil, or water availability often limit a farmer’s ability to switch crops easily. Iowa soybean growers, for instance, can’t start growing rice, which requires heavy irrigation.)

Yeah, that’s true for rice, but Stokstad solves his own dilemma because Iowans and most of the rest of the American Midwest COULD grow wheat in areas where surplus corn is currently grown and fed to livestock (if the relative price of wheat vs corn incentivizes the substitution).   Now we have increased core staples (corn, soybeans, wheat) to all developing regions.

  • Note that increased wheat production would also alleviate the purported shortage of wheat experienced by Asians as the developed world substituted more grain for meat.
  • As the Godfray article points out, livestock also lead to significant increases in methane emissions.

Godfray also adds a few points why reducing meat consumption may not be a complete salvation:

  • Meat types vary in their production efficiency, meaning that some meats like poultry require less energy and water than other meats like beef.  Better breeding might be able to increase efficiency even more.
  • A lot for livestock are grass fed on marginal pastures on which we can’t grow grains.
  • Livestock are often important for other things, like manure fertilizers, plowing and transportation

There’s something to be said about the first point.  As the last post shows, eating beef is more energy intensive than poultry.  The second point is irrelevant— just because some animals are raised on marginal lands doesn’t change the fact that we still feed one third of global grain supply to the remaining livestock.   Again, the point is not to say that we need to eliminate meat consumption just for the sake of it.  We are saying that we can recoup 33% of the grains fed to livestock not fed on grass.  That’s the issue.

Bottom line: I applaud the search for factors that could potentially complicate simple explanations.  That’s a good thing for anticipating unexpected surprises that could appear during a big shift like dramatically reducing meat consumption.  And to be fair, all of these articles acknowledge that reducing meat can be part of an overall strategy to feed more people.

However, the Science articles err on the side of being too dismissive of the impacts that reducing meat consumption can have.

Is this a dose of reality considering that people won’t reduce meat consumption that much?   Maybe.  But I’d rather see Science address what is possible in addition to what is probable.  What we mainly get is the latter.

1Stokstad, E. (2010) Could Less Meat Mean More Food? Science 327: 810 – 811.
DOI: 10.1126/science.327.5967.810

2Godfray, H.C. et al. (2010) Food Security: The Challenge of Feeding 9 Billion People. Science 327: 812 – 818. DOI: 10.1126/science.1185383


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2 Responses to “Science Magazine considers whether decreasing meat consumption can increase global food security”

  1. Danny Ducat says:

    I read the “Could More Meat Mean Less Food” a few months back and was so frustrated with it that I have come back to reread it a couple times and have kept wondering what exactly I was missing and why the logic seemed so misleading to me. I too, agree with you that it was quite interesting to see an article discuss the factors that might confound what, on the face of it, seems like a very simple equation (i.e. less meat = more food calories in the world). It challenged my assumptions about how large of an impact that en masse adoption of diets less rich in meat would have, yet I think that the article’s main premise seems to rely on too simplistic of a change in variables and overhypes its angle (perhaps because it makes for more controversial/entertaining journalism)

    The modeling seems to keep the eating habits of all non-developed nations unreasonably rigid for one thing. Further, the modeling relied on a purely voluntary 50% reduction in meat consumption that is not tied to changes in meat cost/taxes (a variable change that seems both too simplistic and unrealistic). To be fair, the article later quotes Lester Brown as saying that a meat tax would be a good way to go, but seems to fail to address the obvious question about what models would predict were that strategy (or other incentive measures) used.

    Anyway. I’ll stop my venting, but its good to know that a few others out there also thought the tone and approach of the article was more than a little misleading. Thanks for your great post on the matter. Keep up the good work!

  2. Eve A says:

    Although I didn’t read the original Science article, I’ve read the your quotes from it. The quotes seemed to have the agenda to rationalize meat eating. To vegan ears it sound like the author doesn’t want meat eating to have any impact on world hunger. For example the idea that developing countries will eat more meat if we eat less seems totally unsubstantiated. Who’s to say developing nations would choose to squander environment, health and ethics the way we have for generations.


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