"Caloric imbalance causes obesity, so in the sense that any one part of the diet is contributing excess calories, it's contributing causally to the obesity," the American Cancer Society's Dr. Michael Thun said. "It doesn't mean that something is the only cause. It means that in the absence of that factor there would be less of that condition."
Does it merit a warning on soda cans?
"I think it would be a good candidate for a warning," Thun said. "It's something that should be seriously considered."