Prunes are fun fiber fruits that help resolve constipation likely because of their naturally occurring sorbitol—a form of sugar that is hard to absorb and can help soften stools. Prunes also have tons of important vitamins, minerals, and antioxidants—all this in a tiny, tasty, low-calorie package. An apple a day is important, but a prune a day works wonders to prevent constipation and keep young bodies healthy in the first place.