I consciously approached this issue when I was pregnant. Until the age of 7 my son didn`t eat sweets and fast food at all, and as a result he`s in great shape now - which isn`t the case with his classmates... so I think that, yes, parents are responsible for childhood obesity. How should a parent go about dealing with it? Of course sports and dietary adjustments. Yes, the child may not like it, but you should talk to him, try it first in the form of playful would you rather questions. Then gradually add vegetables and lean meat to the diet - just don`t change it drastically, it`ll lead to breakdowns.