Rhubarb
Rhubarb contains high amounts of fiber and it has natural laxative properties that help promote bowel movement. Studies show that one stalk of rhubarb contains about 1g of fiber which is usually bulk-promoting insoluble fiber. Rhubarb also contains a compound known as sennoside A, which has a laxative effect. Sennoside A reduces the levels of aquaporin 3 [7], a protein that controls water transport in your intestines. Reduced quantity of AQP3 causes increased water absorption, which softens stool and promotes bowel movements. Rhubarb can also be added to a variety of baked goods or added to oatmeal or yogurt.