This is a very good first step - now we need more research into whether this holds for non-obese kids who are not Hispanic or black.

I.e. does cutting out almost all added sugars from the diet of a normal weight kid improve health outcomes?

Also note that the lead Author is Robert Lustig - I first ran into a lecture called "The bitter truth" by him against Sugar. So it seems to be a pet crusade of his (not that that invalidates the result).