It's no surprise to low carbers, but a recent study in Pediatrics has proven that kids who drink fruit juice get tubby, because they get all of the fruit's sugar and none of its fiber.
Just look at one 8-ounce serving of pineapple juice. It has 34g of carbs in it. In comparison, you can get 12 ounces of regular Coke and only get 29g of carbs. If you actually eat the FRUIT itself you do pretty well, because it is packed with fiber and nutrients. But if you only drink the strained, processed, filtered version, you get pretty much sugar, water, and flavor.
The study in fact found that kids who had one or two glasses of juice a day had TWICE the chance of becoming obese.
I have heard of parents putting coke into their infants bottles, because they figured the kids would like the sweet flavor. Sure they do! And this starts them on a path to becoming rotund and having rotted-out teeth, while their bones disintegrate.
We don't have to look that far back in history to find a healthy diet for kids. They should drink milk, for strong bones. Water, at least 4-6 glasses a day, for proper hydration. Kids don't need soda or sugar in their diet. They need healthy, fresh fruits, vegetables, complex grains and proteins. Kids do not feed themselves. It's up to us adults to provide them with healthy foods, so they grow up strong and healthy.
Fruit Juice Carb Counts
Lisa Shea's Library of Low Carb Books