When most people realize they are constipated, they reach for the fiber supplement. That's usually a mistake. Fiber from juicing, however, sometimes works wonders.
What Doctors Tell Us About Fiber and Constipation
The conventional medical wisdom is that fiber prevents constipation by acting as a bulking agent. Fiber absorbs water and presses the stool against the walls of the colon, allowing bowel movement with less muscle contraction.
Typically, doctors advise their constipation patients either to run out and buy a psyllium powder product such as Metamucil, Fiberall, Bulk-K, or Fibro-XL, or to get a synthetic methycellulose product such as Citrucel. Any product that contains psyllium can ferment in the gut and cause gas, and the flavored versions of psyllium powder are 50% sugar. Methylcellulose doesn't cause gas, but it can cause dehydration by drawing water out of the bloodstream into the bowel.
Both the herbal fiber supplement psyllium and the synthetic fiber supplement methylcellulose add bulk to the stool so the muscles lining the intestines don't have to work as hard to push stool downward and outward. Adding bulk to stool, however, is all psyllium and methylcellulose can do. Unless nutritional supplements such as calcium are added at the factory—and calcium actually increases constipation—psyllium and methylcellulose don't come with the nutritional benefits associated with fruits, vegetables, and whole grains.
Soluble and Insoluble Fiber
Fiber is the indigestible “bulk” in plant foods. It can't be digested by the human digestive tract, but it can be digested by the probiotic bacteria that live in the human digestive tract. Plant fiber is either soluble in water or insoluble in water. Citrus, oat bran, barley, beans, and peas contain soluble fiber. Wheat bran and certain leafy vegetables contain insoluble fiber. Generally, it's better to get soluble fiber rather than insoluble fiber.
The problem with insoluble fiber is that it slows down the transit of food through the stomach. This means that you feel full longer, which may or may not be desirable, depending on whether you are trying to diet, but it also means that your stomach produces more acid that can fuel heartburn or gastroesophageal reflux disease.
Citrucel, by the way, contains methylcellulose made by treating wood pulp with lye. It does not contain soluble citrus fiber. Benefiber, on other hand, contains wheat fiber that is treated with enzymes to make a water-soluble wheat dextrin. The best way to get the benefits of fiber with the full range of vitamins, minerals, and other nutrients, however, is to drink citrus juice or eat small servings of beans and peas every day. But don't start treating constipation by adding fiber.
Fiber Doesn't Come First
The real benefit in fiber for constipation isn't its use as a bulking agent. The real benefit in fiber for constipation is feeding probiotic bacteria, which grow to form 5 to 20 times as much bulk as the fiber itself.
That's why it's important to establish healthy probiotic bacteria in the colon before taking fiber or eating more high-fiber foods. It usually takes about two weeks of taking a probiotic supplement or eating yogurt with live cultures to build up enough bacteria to ease bowel movement. When you have built probiotic bacteria, then add fiber to your diet. The bacteria will keep the fiber from forming bezoars that can clog your colon even more, and also release small amounts of folic acid and vitamin K into your bloodstream to support your general health.
And before you do probiotics, try juicing. Prune and pear juices add water to stool. Banana and tomato juices speed up the movement of digested food through the digestive tract. They are non-addictive laxatives that help to reestablish regularity while providing a range of nutrients that are never provided by medications or over-the-counter fiber products.