Forego a Hamburger, Feed a Person
September 5, 2013
I eat meat. More specifically, I eat feedlot beef from major supermarket chains and generally enjoy it. Nonetheless, the implications of a recent study have me questioning whether I will eat meat in the future.
In their paper, Redefining agricultural yields: from tonnes to people nourished per hectare, Cassidy et al. present the case that we could feed an additional 4 billion people by growing food for people rather than for livestock. We could do this because feeding crops to livestock is inherently an inefficient way to feed people. In the U.S. (worst case country in this paper), only 1/3 of the calories produced per acre (pre-waste) actually make it to people, mainly due to corn being grown on a large amount of land but being fed to livestock, where most of the calories are lost. The authors estimate that “The US agricultural system alone could feed 1 billion additional people by shifting crop calories to direct human consumption.”
4 billion people! 1 billion from U.S. agriculture alone. Those are numbers that matter. Many experts think we will have 9 billion people to feed by 2050 and many recent conferences, meetings, and efforts are focused on just how to do this. Biotechnology? Increased fertilizer and other inputs? Increased irrigation? Experts say that these will be required to make up the yield gap between current yields and the best-observed yields. However, despite the talk of sustainable intensification, at least some of these strategies, as currently practiced, have negative effects on the environment. And if implemented fully, they would only raise yields by 45-70%, not the 70-100% increase we need to feed all 9 billion people.
Given this sizable problem, and all the money and thinking going towards solving it, I was astonished (although not surprised, I had seen the argument before) at the implications of the Cassidy paper. If we could feed 9 billion with our current land and yields, we would not have to spend lots of time and money trying to continually increase yields AND do it sustainably. We would not have to fully adopt every new technology available. We could focus on addressing current sustainability problems. This would be a much easier task, especially when facing other large problems such as climate change and adjusting our economies to a stable population.
Is it as simple as saying “I will not eat meat so that others can live?” Perhaps for the individual, but it would require drastic changes in our cropping, farm program, and food distribution systems. We have a huge investment in breeding, production technologies, infrastructure, farm equipment, processing and transport systems, all focused on corn. Not to mention a large number of farmers who know how to raise corn well.
There are also cultural (Beef. It’s what’s for dinner), economic (can those who need food pay for it?) and political (food distribution; corn and ethanol subsidies) challenges to this solution. Ideally, meat would become increasingly expensive, people would reduce its consumption on their own, and farmers would have time to transition to different cropping systems. All this would require leadership to enact policy changes.
Are the numbers in this paper reasonable? I looked over the major assumptions (you can too, the paper is available to anyone) and did not see any glaring problems. Given that these kinds of global studies are always just estimates, I find comfort in the number 4 billion. If, as experts predict, we only need to feed another 2 billion (current population estimate is 7.1 billion), then we have 2 billion in slack. This could potentially make up for resistance to change in Western countries, or for China and other developing economies going on a meat-eating spree for a while.
What this paper points out is that there is a clear solution to the problem of feeding 9 billion people. Given the alternatives, I think this should be a major part of our strategy in feeding the world’s future population. I eat meat, but I would give it up to feed other people. Would you?
Emily S Cassidy, Paul C West, James S Gerber, Jonathan A Foley. Redefining agricultural yields: from tonnes to people nourished per hectare. Environmental Research Letters, 2013; 8 (3): 034015 DOI: 10.1088/1748-9326/8/3/034015