I would never give a child candy before bed. Actually, I never gave my son candy at all when he was small.
I would suggest yogurt or a fruit. Even graham crackers and a glass of milk would be better than candy.
This question makes me giggle because when my son was first married he told his new wife he would like something sweet to eat. Being the little sweetheart that she is, she brought home a bag FULL of a variety of candy bars. He looked in the bag and tossed it on the coffee table and said "When I ask for something sweet I mean home made baked goods."
Unfortunately he grew up in a home where cooking any baking was a given so he expects it. He also cooks in his home now.