Kids shouldn't have candy when they are good, either. Candy or sweets should be scheduled such a dessert on Sunday, or a treat on certain days. Have you looked around at the obesity in our population? Sugar is usually one of the top three ingredients in every popular cereal on our grocery shelves, and in almost every food! Why do you need to give your child candy? Wean your child off candy and replace it with something healthy like peanut butter on a celery stick. Of course that means you need to stop eating it too.
Candy should be given in moderation. I am not sure but please do not use candy to bribe your kids into be being good, reward them with trips to the park or store where they can get plain yogurt and fruits so they make a custom flavors.