On the topic of Kids...When I was young I would routinely give up foods because of one bad experience. One of those foods was Milk. About 3rd Grade, the School switched from Whole Milk to Low-Fat Milk. Not knowing what had happened, I drank some and quit drinking milk as a result. I still ate Ice Cream on occassion and Cheese frequently...and never had a problem as a result of not drinking milk. I've started using Soy Slender and Carb Countdown since LCing. That said, Whole Milk is relatively good food for you. It is loaded with Vitamins and Minerals, the Carbs aren't that bad [for a person not on an induction diet,] and Lactose is Low Glycemic. It is definitely better [for you] than Soda or Juice any day. Low-Carb milks are even better because they still have most of the Nutrition, but not the Carbs.

As for Grains, humans eveolved fine without them...I found a food journal I'd kept in 6th Grade and it showed that at that time I ate about 1 serving of Grain a week. Interestingly enough, at that same time I was 200+ pounds lighter and 24-28" smaller [in the waist] than I was when I started LCing. I was also able to play sports without winding, could run for extended distances, and could do chin-ups/push-ups/sit-ups no problem. It was only when Grain [Rolls, Graham Crackers, Rice Cakes, Cake, Doughnuts, Biscuits, Rice, and Pasta] became a daily [several servings a day] foodstuff that I began to really pack on the pounds and get winded easily.

I see no reason a kid couldn't eat Grain once a week or so...and stay healthy. That is as long as Whole Grains were emphasized and he/she did not become addicted to the Grains. I just don't believe it is absolutely necessary for a healthy diet. The Inuit don't have Milk or Grain and they do just fine. Same goes for many other Hunter-Gatherer tribes from varied parts of the world before they recently succombed to the convinience of processed carbs.