We definitely appreciate good meat and dairy (mmm, milkshakes) around here. But any moral and ethical objections you might have to eating meat and dairy aside, the sad fact is that both these things just aren’t very efficient ways to get energy (in the form of ingested calories) into human mouths.

Vox brought the map above to our attention, which is taken from a very fascinating and graphically-rich National Geographic piece by Jonathan Foley called “A Five Step Plan to Feed the World.” The problem with considering global hunger and the future of agriculture is that both present intimidatingly large problems that require multiple levels of problem-solving. A piece like this is valuable, mainly because it succeeds in breaking the problem down into something we can wrap our brains around—while simultaneously not oversimplifying. That’s no easy task.

One of the main points NG drives home is that if population trends continue as expected, the globe is on-track to host about nine billion people by the year 2050. The piece also notes that only 55 percent of the land the world currently uses for agriculture actually goes directly to feeding humans. The rest is used to feed animals and make biofuels.

Another National Geographic piece says the best way to think about land the world uses for agriculture is to think about the planet like an apple, sliced into four equal wedges. Three of those wedges are water, and half of the final wedge is full of land that can’t support agriculture for various reasons (such as deserts). So 1/8 of the planet is left for agriculture, and 3/4 of that 1/8 is paved over with modern human civilization. The conclusion this piece reaches is that we actually only use about 1/32nd of the earth’s surface for agriculture.

Here’s where that caloric efficiency problem comes into play: As different cultures gain prosperity, they tend to shift toward rich meat and dairy-based, Western-style diets. Foley estimates that for every 100 calories of grain we feed to animals, we get back 40 calories of milk, 22 calories of eggs, 12 calories of chicken, 10 calories of pork, or just 3 calories of beef. Those numbers come from factory-farmed, grain-fed livestock. Foley is cautiously optimistic about prospects for grass-fed livestock:

Finding more efficient ways to grow meat and shifting to less meat-intensive diets—even just switching from grain-fed beef to meats like chicken, pork, or pasture-raised beef—could free up substantial amounts of food across the world.”

While there’s still a lot of work to be done, the good news is that it isn’t all doom and gloom on the feeding-the-world-front. According to data published by the Nature Conservancy, we’ve actually become more efficient at producing more food with less land since 1998.

GlobalLandAg

GlobalFoodSupply

Graphs: The Nature Conservancy

Basically, the takeaway from all this is that global citizens need to double down on efforts to make agriculture simultaneously more productive and sustainable. Interestingly, what’s physically good for us humans is also good for the planet.

In other words, to quote Michael Pollan, “Eat food. Not too much. Mostly plants.”

[via Vox, National Geographic]

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