DR Robert H. Lustig argues that fructose (too much) and fiber (not enough) appear to be cornerstones of the obesity epidemic through their effects on insulin.
I am seeing that Fructose is a major player in this problem, whether in HFCS or Sucrose, and it appears to be causing the obesity epidemic throughout the world.
The fiber in fruit makes fructose less harmful, which is why fruit is not a problem, but when fructose is removed from its fiber background, it causes everything associated with Metabolic Syndrome.