Corn Burger

Your burgers are made from corn.

Jahren and her colleague Rebecca Kraft collected hamburgers, chicken sandwiches and fries from three separate Burger King, McDonald's and Wendy's locations in six U.S. cities: Baltimore, Boston, Detroit, Denver, Los Angeles and San Francisco. The scientists were looking for the amount of carbon 13 (¹³C), a variety of carbon with an extra neutron (known as an isotope) that makes its atom heavier.

Corn tends to have more of this ¹³C than other plants. That telltale signature persists as the corn travels through the complex system that turns it into feed, which is consumed and processed by cattle to grow tissue. It continues after the animals are slaughtered and the meat is cooked. The result: 93 percent of the tissue that comprised the hamburger meat was derived from corn.

In fact, only 12 samples from the entire country did not show this unique corn signature: all from a Burger King on the west coast. "My best guess is that it represents meat from another country," Jahren says.[...]

As Jahren notes, Americans spend more than $100 billion a year on such fast food, making it a significant part of the diet. "Diet related disease is causing more and more suffering in this country and the information you can get is either vague or nonexistent," says Jahren, who spent the last two years trying to get information about what specifically goes into fast food at these chains and how it is made, with no success. "You shouldn't have to use stable isotopes to get the answer to what's in something I just spent my money on and am about to put in my body."

We might not eat it if we knew.

Via Ezra Klien