Wansink said that more research is needed to assess the need for government control over other types of junk food as well. Such laws could backfire in a number of ways, he said: People sometimes respond to lower fat and calorie choices by eating a greater number of total calories. They may cut back on healthy foods in order to compensate for the higher cost of their indulgences. Or, as in Denmark, local businesses may pay the price when consumers take their business elsewhere.
Currently trans fats, salt and sugar are the ingredients most often taxed or rationed. Farley said there is strong evidence each of these cause serious health problems. He doesn't see any other foods meeting the same criteria right now. Of course, that could change. And, unlike smoking, where there is one product to tax and regulate, it may be difficult to know where to draw the line.
As for the Danes, Popkin said he thought they gave up on their saturated fat tax too easily. He's disappointed they didn't stick it out longer.
But the Danish government has already moved on. They've asked Wansink to explore more positive ways to encourage healthy behavior. He's currently spending two years transforming supermarkets on the Danish island of Bornholm (population 40,000) to make the sales of healthy foods more appealing for consumers and retailers alike.