DUBNER: Right now, we’re talking in the year 2017. A lot of people now are convinced that the U.S. government and many others erred terribly in declaring fat to be the cause of obesity. Many people now believe, as you argue, that sugar is a much bigger villain. How do we know you’re not the guy that’s wrong this time, that you’re not just another — perhaps well-intentioned — big-brained do-gooder who is making a massive mistake?
LUSTIG: An awfully good question. This is known as the pessimistic meta-induction theory. What it says is, “Everything we knew 10 years ago is already wrong, and everything we know today will be wrong 10 years from now. Why should we do anything differently when we know that whatever it is that we believe today will end up being wrong?” If you play that game, then you might as well never do any research, never do anything at all, and live with the current dogma.
– FREAKONOMICS podcast – There’s a War on Sugar. Is It Justified?