Photo by Kris Krüg

(Updated below with Michael Pollan’s response)

You want some petroleum with that Big Mac?

Journalist and food writer Michael Pollan broke down the hidden cost of America’s best-known burger on Saturday to an eager audience at the Poptech conference. He traced the Big Mac’s origins all the way back to the oil fields, used to make fertilizer that is crucial to the corn grown for cows in massive feeds lots.

“Our meat eating is one of the most important contributors we make to climate change,” said Pollan, who is best known for his book “The Omnivore’s Dilemma.”

Reuters will be covering the PopTech conference, dedicated to “world-changing people, projects and ideas,” from Oct 21-25, including interviews with food writer Michael Pollan, Nike sustainability expert Lorrie Vogel, and many more.

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