Soluble fiber dissolves in water and forms a gel-like substance in the digestive system. It helps lower blood cholesterol and glucose levels, making it beneficial for heart health and blood sugar control. Foods rich in soluble fiber include oats, beans, lentils, fruits, and vegetables. Insoluble fiber, on the other hand, does not dissolve in water. It adds bulk to the stool and aids in digestion by promoting regular bowel movements. This type of fiber is found in whole grains, nuts, seeds, and the skins of fruits and vegetables. Both types of fiber are essential for a balanced diet.