This helps you to feel full longer and is one reason why fiber may help with weight control. Insoluble fiber, found in foods like dark green leafy vegetables, green beans, celery, and carrots, does not dissolve at all and helps add bulk to your stool. This helps food to move through your digestive tract more quickly for healthy elimination. Many whole foods, especially fruits and vegetables, naturally contain both soluble and insoluble fiber. 9 Health Benefits of Fiber There's no shortage of research showing how fiber may boost your health.