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There’s a powerful narrative being told about the world’s food system — in classrooms, boardrooms, foundations and the halls of government around the world. It’s everywhere. And it makes complete sense when you listen to it. The problem is, it’s mostly based on flawed assumptions.

You’ve probably heard it many times. While the exact phrasing varies, it usually goes something like this: The world’s population will grow to 9 billion by mid-century, putting substantial demands on the planet’s food supply. To meet these growing demands, we will need to grow almost twice as much food by 2050 as we do today. And that means we’ll need to use genetically modified crops and other advanced technologies to produce this additional food. It’s a race to feed the world, and we had better get started.

To be fair, there are grains of truth in each of these statements, but they are far from complete. And they give a distorted vision of the global food system, potentially leading to poor policy and investment choices.

To make better decisions, we need to examine where the narrative goes off the rails. 

Changing Diets, Not Population Growth, is the Dominant Driver of Food Demand

While we often hear that population growth, and the need to feed 9 billion people by 2050, is the driving issue for agriculture in the coming decades, the math doesn’t add up.

There are more than 7 billion people on Earth today, and we’re expected (if current demographic trends continue unabated) to reach 9 billion by mid-century. Two billion more people in the next 40 years — that’s roughly a 28 percent increase. If those additional 2 billion people were to eat the average diet (which is actually unlikely, since most of these people will be added to the poorest regions of the world, where diets are very minimal) that would mean we need roughly 28 percent more food. It’s just simple math.

It’s crucial to note that we’re talking about the world’s choices, not a predetermined path. What we choose to do about population growth, and especially what we do about diets, will determine how much food the world ultimately needs.

So where does the “twice as much” idea come from? Mostly from assumptions about changing diets, not population growth alone.

In fact, ecologist David Tilman, a friend of mine, and his colleagues have shown that changes in diet will likely be the dominant driver of future food demand. The reason is simple: While population is projected to grow by 2 billion between now and 2050, there are about 3 to 4 billion people on Earth already who are getting richer — mainly in China, India and some other countries — and, if recent history is a guide, these richer people are expected to eat richer diets. That means 3 to 4 billion more people eating more meat, more dairy products, and other rich foods, putting tremendous pressure on the global food system.

Food Demand: We Have a Choice

According to Tilman and his colleagues, increasing wealth and projected increases in meat consumption could drive up global food demand much more than population growth alone. The researchers suggest that roughly one-third of future food demand increases may come from population growth, and roughly two-thirds may come from increasing wealth and richer diets. Of course, increasing reliance on crop-based biofuels would only add to the pressure.

But it’s crucial to note that we’re talking about the world’schoices, not a predetermined path. What we choose to do about population growth, and especially what we do about diets, will determine how much food the world ultimately needs. While there are powerful demographic and economic forces at work here — with a great deal of momentum behind them — the path is still ours to choose. Concerted efforts to reduce population growth, but more importantly to steer diets onto a more sustainable path, could dramatically reduce these projected demands. The script hasn’t been completely written yet.

People often confuse growing more crops with making more food available to the world. They’re not the same thing.

We could do much to ease the pressure on the global food system by looking first at transforming diets where they are already very rich, like North America and Europe. Shifting to less meat-intensive diets in these regions could have dramatic impacts on the food system. But just as important is to focus on the changing diets of newly affluent people — for example, new middle-class people in the cities of China, India, Indonesia and elsewhere. Will they continue to eat a mostly plant-based diet, with little waste, or will they move toward a meat-rich Western diet? In fact, what these people choose to eat in the coming decades will determine much of the future of the world’s food system. 

Growing More Crops Is Not the only Way to Get More Food on the Table 

But no matter how much we can curb the growth in future food demand, we will need to grow more crops, right?

Yes, we probably will need to grow more crops, but not as much as this narrative suggests. That’s because people often confusegrowing more crops with making more food available to the world. They’re not the same thing. What we really need to do isdeliver more food and good nutrition to the world. And there is another way to deliver more food to the world besides simply growing more crops: Better use of the crops we already grow, making sure they create as much nutritious food as possible.

Sadly, we rarely hear about this option, and are instead told over and over again about ways to grow more crops. It reminds me of when some politicians have talked about energy policy in the past, and yelled “Drill, Baby, Drill!” I think we’re obsessed with a “Grow, Baby, Grow!” mentality in agriculture too. In this mindset, it’s all about supplying more — more energy, more crops, more whatever. What’s missing is how we can better use the resources we have today, through reducing waste and better managing our demands. Buying a bigger furnace for your house because it’s cold and drafty in the winter, without even checking if the windows are well sealed or if the attic and the walls are insulated, is shortsighted and misguided. The same is true in agriculture.

If we need more food on the table — and we very likely will — a sensible strategy would take a balanced approach, looking at supply side and demand side solutions. Why would we leave half of our potential solutions off the table?

Food waste alone takes roughly 30 to 40 percent of the world’s calories, but it rarely receives the attention is deserves. (While we can’t fully eliminate food waste, surely we can cut it substantially in the coming decades.) Meanwhile, the use of crops for animal feed (instead of for direct human consumption) can be extremely inefficient in feeding people. Furthermore, some key crops are increasingly being used for biofuels, at the expense of producing food. Altogether, this leaves tremendous opportunities to feed more people with the same level of crop production by shifting more of our animal agriculture to pastures and grass-fed operations, and moving biofuel production away from food crops. Basically, how we use crops matters as much as how many crops we grow.

My colleague Emily Cassidy recently made this point very clearly. She noted that the typical Midwestern farm couldtheoretically provide enough calories to feed about 15 people daily from each hectare of farmland. But there’s a catch: People would need to eat the corn and soybeans these farms growdirectly, as part of a plant-based diet, with little food waste. What Cassidy found was that the actual Midwestern farm today provides only enough calories to feed roughly five people per day per hectare of farmland, mainly because the vast majority of the corn and soybeans are being used to make ethanol or to feed animals. Amazingly, feeding five people per day per hectare is comparable to the production of an average farm in Bangladesh today.

In other words, we grow a lot of crops, but it’s not translating to as much food. So we can deliver more food by rethinking how we use our crops — whether for plant-based diets, feeding animals to make meat and dairy products, or making biofuels — and by not wasting them. If we need more food on the table — and we very likely will — a sensible strategy would take a balanced approach, looking at supply side and demand side solutions. Why would we leave half of our potential solutions off the table? 

GMOs and Other Advanced Technologies Aren’t Really Giving the World More Food

The final piece of the widespread food narrative is that we will need genetically modified organisms and other advanced technologies to feed a growing world.

I’m not so sure.

Before I begin, I am going to state for the record that I hold a neutral position on GMOs. From my read of the current scientific literature, I do not believe that GMOs pose an obvious health threat (although more research should be done on this), nor do they seem to pose any direct environmental threat. Most of the concerns I hear about genetically modified crops are mainly related to how they are used by large corporations in giant monocultures, which are experiencing herbicide-resistant weeds, declining pollinators and so on. But these seem to be mainly problems with vast monocultures, not GMOs per se. GMOs may, in fact, be able to reduce pesticide use and help farmers reduce soil tillage, leaving more organic matter and nutrients in the soil. Maybe GMOs can actually do some good, if used wisely. So I try to keep an open mind about them.

While future genetically modified crops could add other beneficial plant traits, which might help boost productivity in crucial crops, I think the best answers lie elsewhere.

But I am unsure whether GMOs are actually delivering substantially more food to the world. In fact, as far as I can tell, they aren’t. Why? Just consider how GMOs are used: Roughly 10 to 15 percent of the world’s cropland is growing GMOs today, mainly for five crops — feed corn, soybeans, cotton, canola and sugar beets. The vast majority of those crops are not feeding people directly, but rather are being used as animal feed, biofuel feedstock or fiber. Of this list, only canola and sugar beets are mainly “food” crops. Furthermore, the GMO traits currently being used today mainly give plants the ability to fight off insects (the so-called “Bt” trait) or to withstand herbicides (the so-called “Roundup Ready” trait). While reducing losses to insects and weeds is important in maintaining high crop yields, most farmers, especially in the U.S., simply switched one method of insect- and weed-control (e.g., more frequent tillage, a broader mix of herbicides and pesticides) with another. These GMOs haven’t made fundamental changes in plant growth or photosynthesis (that has not yet been done with GMOs in practice); they mainly traded one set of pest- and weed-control systems with another. These “turnkey” solutions for pests and weeds have made big farms more efficient, more profitable, and maybe offered some environmental benefits because of reduced tillage and chemical use. But large, sustained yield improvements have not been a major outcome, except for possibly cotton in India, where pest losses were quite severe and ongoing.

While future genetically modified crops could add other beneficial plant traits, which might help boost productivity in crucial crops, I think the best answers lie elsewhere.

Work in our lab, led by Nathan Mueller, has shown how focusing on improved soil nutrition and water availability is key to boosting crop yields around the world. Mueller’s research shows that in developing countries many places exhibit substantial “yield gaps” — the difference between the crop yields we see today, and the crop yields that are possible with improved farming practices — which can be largely closed by improving agronomic practices, such as adding organic matter, small doses of fertilizer (chemical or organic), and extra water (especially with efficient systems like drip irrigation). At this point, it’s hard for me to imagine how GMOs would dramatically help farmers in poor countries right now, where yield gaps are large, especially when yields are currently limited by the availability of soil nutrients and water.

The prevailing narrative about the global food supply needs to be replaced by a more accurate narrative that can better guide future investments and decisions.

Of course, GMOs and other advanced technology might be able to help in the quest for a food-secure world, especially if they are not primarily used in large monocultures of nonfood crops, but they are no silver bullet. Hopefully they can help. But in the near-term, I’m placing my bets on lower-technology approaches, targeted at small landholders, especially for improved soil and water management.

Shifting to a New Narrative

While the prevailing narrative about the global food supply is persuasive and sounds very logical, it is actually based on several wrong assumptions. It needs to be replaced by a more accurate narrative that can better guide future investments and decisions.

The new narrative might sound something like this: The world faces tremendous challenges to feeding a growing, richer world population — especially to doing so sustainably, without degrading our planet’s resources and the environment. To address these challenges, we will need to deliver more food to the world through a balanced mix of growing more food (while reducing the environmental impact of agricultural practices) and using the food we already have more effectively. Key strategies include reducing food waste, rethinking our diets and biofuel choices, curbing population growth, and growing more food at the base of the agricultural pyramid with low-tech agronomic innovations. Only through a balanced approach of supply-side and demand-side solutions can we address this difficult challenge.

These are big challenges, and there are no simple solutions. As a first step, though, we at least need to be sure that we get the story about the food system straight. After all, if we’re not even starting at the right place, we certainly will not end up at the right destination. 

http://ensia.com/voices/changing-the-global-food-narrative/