While I don't have any children of my own I've definitely dealt with the backlash from smoking and diet changes in my social life. When I started smoking I almost instantly noticed positive effects but I know the stigma associated with it. My mom her friend and uncle all react with the cancer slogan even calling nicotine poisoning. After going to a chistmas party at Golden Coral I went outside to smoke. While two young kids passed by the sister told her brother to cover his mouth all the while being unaware of the true toxins in the food they were about to eat! But I digress, I can say what got me off of candy dairy etc was the pain involved and eliminating these things took research but since a child isn't going to do this like Alana said it would be best to lead by example but in the end she must choose her own way. You can also try wearing her off that food with homecooking with a "cheat day" like Laura has done as well.