The Truth About Sugar

The Other Side of the Story

Lustig’s idea sounds appealingly logical, but many experts don’t buy his toxic-sugar theory. David Katz, M.D., M.P.H., is one such expert. He has written and spoken extensively on the subject. “That talk, what made it so viral was the extreme position,” says Katz, director of the Yale University Prevention Research Center and an EatingWell advisor. “Vilifying a certain nutrient is a good-versus-evil worldview. It’s easy to get people excited if you say the most extreme thing.”

Though Lustig is a respected physician, he isn’t a fructose researcher (he has only one original scientific paper on the subject, based on government-generated—not lab-generated—data). Most of his 90-plus published scientific papers focus on overweight children. And before his infamous lecture, only two mentioned fructose at all; since 2009, he’s published six papers that mention fructose, mostly editorials, reviews and commentaries on his theory.

But he’s not the only one to theorize that fructose is causing some of our modern health problems. In 2004, George Bray, M.D., at the Pennington Biomedical Research Center in Louisiana, and Barry Popkin, Ph.D., at the University of North Carolina at Chapel Hill, noticed that rising rates of obesity paralleled an increase in sugar consumption and they loosely attributed this to the harmful way our body metabolizes fructose. Other studies have since more strongly linked consuming sugar-sweetened beverages like sodas and juices with obesity, at least in children and adolescents, and for years researchers have been giving animals extremely high doses of fructose to create metabolic syndrome.

Why, then, is Lustig famous for the theory?

Next: Testing Lustig's Theory »