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Sweet & Sour

Robert Lustig, MD ’80, is sounding the alarm about what he sees as dangerous levels of sugar in the American diet.

Man on a Mission: Robert Lustig, MD '80, calls excessive fructose consumption a public health crisis.

Man on a Mission: Robert Lustig, MD ’80, calls excessive fructose consumption a public health crisis.

In April 2011, the New York Times Magazine ran a cover story that asked a pithy, pointed question: Is sugar toxic? Its author, Gary Taubes, opened the piece by noting that a lecture on the subject given by a pediatric endocrinologist prominent in the anti-sugar movement had gotten more than 800,000 hits on YouTube since it had been uploaded in July 2009. And the video was adding some 50,000 views each month—“fairly remarkable numbers for a ninety-minute discussion of the nuances of fructose biochemistry and human physiology.”

Nearly five years after that story was published, the YouTube tally for “Sugar: The Bitter Truth” stands at more than 6.1 million (video below). And the physician-scientist who gave the talk—Robert Lustig, MD ’80, an expert on childhood obesity at the University of California, San Francisco—is continuing to lead the charge against what he sees as the Western world’s leading dietary demon. He doesn’t mince words. “Fructose is a poison,” Lustig says in his much-viewed lecture—an allegation he has repeated in books, articles, media interviews, documentaries, and countless other talks. “We’ve had our food supply adulterated, contaminated, poisoned, tainted, on purpose. And we’ve allowed it.”

Lustig isn’t just worried about sugary beverages like soda and juice—though he is plenty concerned about them—or dessert items like ice cream, candy, and cupcakes. It may come as a surprise that he enjoys a slice of Junior’s cheesecake whenever he visits New York, or a bowl of bread pudding with whiskey sauce when he goes to New Orleans. His wife is an avid baker—“she’s Norwegian; I can’t stop her; it’s therapy”—who makes cookies for their kids on a weekly basis, though she generally cuts the sugar in any recipe by a third. “I eat her cookies, because they’re worth it; if you’re going to eat dessert, make it a damn good one,” says Lustig, chatting with CAM over (unsweetened) coffee at an outdoor café near his UCSF office last fall. “I’m not a hard-ass, and I’m not a sugar teetotaler in the classic sense. I eat dessert, but it’s got to be a really good one for me to spend my sugar allotment on it.”

One of Lustig’s central concerns is the sugar that’s hidden in the American diet—what’s lurking in products that we don’t think of as particularly sweet. “Fifty percent of the sugar that we consume is in sodas and things we identify as dessert—and that means 50 percent is not,” he says. “Half of the sugar we consume is in foods we didn’t know had it.” That includes such things as pasta sauce, yogurt, salad dressing, breakfast cereal, ketchup, bread, barbecue sauce, and nutrition bars…

This article was excerpted from the March/April 2016 cover story, “Sugar Shock” See below for the full print version.

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