A combination of soluble and insoluble fiber helps maintain normal intestinal function by affecting the consistency of the stool and working as a pre-biotic positively affecting digestion of other foods. Soluble fiber is the form of fiber that dissolves in water. Examples of foods that contain soluble fiber include fruits, oats, legumes and barley. • Insoluble fiber comes from plant cell walls and does not dissolve in water. Examples of foods that contain insoluble fiber include wheat, vegetables, and seeds. Fiber works by both bulking up the stool and retaining water. In addition, bacteria help digest the fiber which produces healthy ingredients for the colon such as short chain fatty acids. Fiber can be beneficial for both diarrhea and constipation depending how much fluid is also taken in with the fiber. Fiber can become a constipating agent if the ratio of fluid taken in is too low. Drink plenty of water! Plant based fiber is also the only natural source of prebiotics, which are the food source for friendly, probiotic organisms in your gut. Fiber also increases the volume and diameter of your stool, making it easier for the colon to grab onto during peristaltic contractions. This makes it far easier for the colon to move waste down and out of your body. Fiber may cause gas and bloating in some people and this may be a function of the amount or the type of fiber. It is important to maintain a 3-1 water to fiber ratio when taking fiber in order to avoid gas, bloating or in some cases constipation.