Wanting the best for your child is a natrual parental instinct, but you have to accept that not every parent feels that instinct as strongly as you do. The best way around the difficulty of allowing your child to mix with children who'se parents do not follow the healthy diet you want for your own child, is to let him have sweets and carbonated drinks on a strictly rationed basis. That way he will not feel exlcuded from his peer group, for reaons which he is too young to understand, but old enough to feel aliented, and you will be able to ensure that his diet is as healthy as you can make it. It is not possible to shield a modern child from all the bad things in the world, but you can only try your best, and allow others to enjoy the same freedom of choice to feed their children as they see fit.