I've just read some research, below, which I think parents will find very interesting. Apparently, telling your child/ren "no" to snack food all the time will often increase their desire for (and intake of) those very foods. Not surprising really when you think how dieting makes you crave the foods you've labelled out of bounds! We always want what we can't have.
If we want to improve our children's eating health, rather than defending the food industry who promote chocolate breakfast cereals with added vitamins as "healthy" and then telling parents, "well, you can just say no" (which we now know doesn't work), maybe we should make it known that we don't want these non-foods thrust at our children during every ad break and at every supermarket checkout!!!