In addition to grains, fruits and vegetables, American farmers raise 7 billion livestock animals [source: Kellogg]. These animals are fed more of our farmed grains than people consume — five times more grain. Interestingly, if these crops were fit for and fed to humans instead of animals, the number of people fed by one farm could skyrocket, and the total tonnage could feed as many as 800 million people [source: Pimentel].
Every year those livestock farms produce a total of 7 million metric tons of animal products. We'll look at beef as our example: When it comes to raising cattle and producing animal protein to sell to consumers, the numbers break down to about 400 pounds of steak, ribs and other cuts for the American population to broil, roast or barbecue from one 700-pound animal [source: Dole & Bailey]. While the exact numbers vary depending on the method of raising the livestock (such as grain-fed and pasture-raised), if you consider one serving to be 3 ounces — the recommended serving, which is about the size of a deck of cards — that one animal contains slightly more than 2,100 servings.
And then there's the matter of farming method.
Put aside the ongoing debate on whether organic foods are more nutritious than their conventionally grown counterparts; when we're talking about how many people can be fed by one farm, we want to know about yield. And when it comes to organic farming methods, studies find that, generally, organic yields fall short when compared to those grown with conventional farming techniques.
However, before you shoot the messenger, it's important to understand that yields depend not only on method, but also on the type of crops we're comparing, in addition to whether we're looking at best-case scenarios or real-life outcomes. Taking those variables into account paints a more complete picture: The numbers may fall anywhere from just 5 percent smaller to as much as 34 percent smaller.
When comparing certain fruits and vegetables, organic yields seem to outperform conventional [source: Gilbert]. Organically farmed corn, for example, produces a 29 percent lower yield than when conventional methods are used, yet organic raspberry yields outproduce conventionally grown berries [source: McWilliams]. Under the best circumstances using the best methods, organic farming produces 13 percent smaller yields, but, overall, typical organic methods produce 25 percent less [source: Gilbert].