Dietary fiber is, in its simplest form, a carbohydrate that comes from plants. Fiber comes in three varieties, each with a different function, so a review of each is in order.

  1. Soluble fiber (apples, oats) dissolves in water, making a gel-like substance that is active in the small and large intestine. Before it reaches the small intestine, it slows stomach emptying and sugar absorption, improving blood sugar control. Also, because it forms a thick goo, it increases stomach distention, leading to earlier satiety and reduced calorie intake. Once it reaches the small intestine, it binds bile acids, causing the liver to use up LDL cholesterol to make new bile. Thus, it lowers serum cholesterol.
  2. Insoluble fiber (whole grains, nuts, vegetable skins) does not dissolve in water and remains intact until it arrives in the large intestine. There, it increases the bulk of the stool, which irritates the colon wall and prompts the secretion of water and mucus, which in turn prompts a bowel movement. The higher amount of fiber results in a lower incidence of colon cancer.
  3. Resistant starch (legumes, cooked and cooled potatoes or rice) is a type of starch that is usually broken down in the small intestine, producing glucose. However, amazingly, when it is cooked and then cooled, it becomes resistant to this breakdown process, arriving intact in the colon where it is finally broken down, providing energy for the cells lining the colon. This increases the colon’s mucosal barrier, which in turn reduces inflammation and helps prevent infection.

Instead of trying to keep up with how many grams of fiber you eat in a day, it is much easier to become a “stool watcher”.  In other words, if you see that your stools are ball-like and hard, you are lacking in fiber and water. If the stool is softer, formed, and easily passed, your fiber and water intake is probably good. Not a pleasant pastime, but certainly an easy method of becoming a healthier you. Never forget your mother’s preaching, “An apple a day keeps the doctor away”.

Dr. Charlie Barnett is a contributor to KnoxTNToday, where he writes a weekly column, DocTalk, sharing his expertise on health and wellness management.

Follow KnoxTNToday on Facebook and Instagram.   Get all KnoxTNToday articles in one place with our Free Newsletter.