The best way to get fiber is naturally, from whole foods in your diet. Most experts encourage eating foods naturally rich in dietary fiber – such as fruits, vegetables, whole grains, beans, and nuts -- because they also provide many other health benefits.
But most Americans struggle to eat the recommended 25 to 38 grams of fiber each day. When you can’t get all the fiber you need in your diet, taking fiber supplements or eating foods and beverages with added fiber is one way to fill the gap. Today there are numerous fiber supplements available, and fiber is being added to a growing number of processed foods. This article looks at the benefits and potential downsides of fiber supplements, and provides tips for how to get the best out of them.
How Fiber Supplements Work
Fiber supplements are usually made from “functional” fibers, which is fiber that is isolated or extracted from plants or animals, with health benefits in humans. They come in a wide variety of forms and flavors -- from powders, oils, and wafers to capsules and chewable tablets.
Common functional fibers include:
- Inulin and oligofructose -- Prebiotic ingredients that can stimulate the growth of beneficial bacteria that may improve immunity or gastrointestinal health.
- Psyllium – Effective in treating constipation and the symptoms of irritable bowel syndrome.
Other functional fibers include: Guar gum, pectin, chitosan, cellulose, methylcellulose, beta-gucans, polydextrose, resistant dextrins, fructooligosaccharides, and acacia fibers.
All functional fibers are either soluble or insoluble. In general, research shows that soluble fiber helps lower cholesterol and may help control diabetes. Insoluble fiber speeds waste through the body and keeps you regular. But fiber supplements may not provide all the same benefits as fiber-rich whole foods. For example, early studies indicated that fiber supplements can aid weight loss, but more recent evidence suggests that they are not effective in reducing weight.
Potential Side Effects of Fiber Supplements
Fiber supplements are a safe and easy way to boost the fiber in your diet. But if you take too much, they can cause some uncomfortable side effects and interfere with your body’s intake of important nutrients.
- Getting too much fiber can cause loose stools, abdominal discomfort, gas, and bloating. Fibers such as guar gum, inulin, oligofructose, polydextrose, resistant starch, and psyllium, have been found to cause abdominal cramping, bloating, gas, and diarrhea -- especially when taken in excess.
- Excess fiber can bind to iron, zinc, calcium, and magnesium and decrease their absorption. And studies have shown that fibers such as pectin and guar gum can reduce absorption of carotenoids, beta-carotein, lycopene, and lutein when consumed at the same time as a meal.
However, adults who consume the recommended amounts of fiber – 25 grams a day for women and 30 to 38 grams a day for men -- are unlikely to have problems with nutrient absorption.