AskIFAS Powered by EDIS


Guide to Fiber Supplements

Wendy J. Dahl

Why might fiber supplements be needed?

Fiber supplements may be needed for older adults suffering from constipation. Constipation is a common health concern and may contribute to a lack of appetite as well as more serious health problems. A number of health conditions, diseases, and medications contribute to constipation. Lack of exercise also adds to constipation. Low fiber intake is a very common cause of constipation.

Figure 1. 
Figure 1. 
Credit: iStock/

How much fiber is recommended?

It is recommended that older women consume about 21g of fiber a day and older men aim for 30g per day (Institute of Medicine, Food and Nutrition Board 2005). However, fiber intakes of older adults may fall below recommendations. It is often difficult for some older adults to meet their fiber needs through diet alone as they eat less food than younger people. Some older adults may avoid some high-fiber foods due to expected problems chewing these foods.

When it is difficult for older adults to meet their recommended fiber intake within their usual diet or when constipation is present, fiber supplementation may be recommended.

Older adults suffering from constipation should consult a doctor or registered dietitian nutritionist (RDN) prior to choosing a fiber supplement.

What types of fiber supplements are available?

There are many different types of fiber supplements available and may be in powder, capsule, tablet, or "chew" form. Fiber supplement powders that can be added to beverages are the most common.

The fiber ingredient will be listed on the label of the fiber supplement. Common fiber ingredients used in fiber supplements include:

  • Wheat dextrin

  • Inulin or Oligofructose (chicory root fiber)

  • Methylcellulose

  • Hydrolyzed guar gum

  • Psyllium

Do fiber supplements prevent constipation?

Fiber works to prevent constipation by bulking the stool, producing larger, soft stools that are more easily passed. To prevent constipation, fibers with the highest stool bulking capacity are recommended. Wheat bran, a fiber found in whole wheat bread and whole wheat cereals, has good stool bulking. It works well to prevent constipation. However, wheat bran and other bran fibers are typically not used in fiber supplement capsules, pills, or chews. Bran fibers do not dissolve in water, so are not found in fiber supplement powders.

Most fiber supplements available in the marketplace contain soluble (dissolve in water) fibers. Some soluble fibers, such as methylcellulose and psyllium, work well to prevent constipation. Other soluble fibers used in supplements may have little to no effect on stool bulking but may increase stool frequency or regularity (Dahl et al. 2014). In general, you need to consume much more of most soluble fibers than bran fibers to prevent constipation.

What are the potential side effects of taking fiber supplements?

Fiber in food and supplements will result in intestinal gas production. Older adults may experience noticeable flatulence (gas), usually within a few hours after taking most fiber supplements. Some people may experience uncomfortable bloating and abdominal discomfort. Increasing fiber intake gradually will help to determine one's tolerance to gas symptoms.

Some fiber supplements contain sorbitol. Sorbitol is not a fiber, but rather a sugar that is not absorbed in the gut. Routine intake of small amounts of sorbitol contributes little to stool bulking and may result in intestinal gas and discomfort. Higher intakes of sorbitol may cause diarrhea.

Do fiber supplements pose a risk for older adults?

Psyllium fiber, which can become very thick when mixed with water, is a choking risk for older adults with swallowing problems. For older adults with normal swallowing, it is recommended that psyllium fiber supplements be taken with plenty of water. Soluble fiber supplements such as chicory root fiber or wheat dextrin do not thicken water or other beverages and therefore do not pose a risk of choking.

Tips for Using Fiber Supplement Powders

Soluble fiber supplements containing either chicory root fiber or various dextrins can be added to many foods and beverages with little or no effect on taste. Try adding to milk, juice, and other beverages, as well as to puddings, ice cream, and other desserts. Adding to soups and casseroles works well, too.

Where can I get more information?

Your local UF/IFAS Extension Family and Consumer Sciences (FCS) agent may have more information and classes for you to attend. Also, a registered dietitian nutritionist (RDN) can provide reliable information to you.

For more information on fiber, refer to the EDIS publication FCS8793, available at For more information on constipation, refer to the EDIS publication FSHN10-07, available at


Dahl, W. J., A. R. Wright, G. J. Specht, M. Christman, A. Mathews, D. Meyer, T. Boileau, H. J. Willis, and B. Langkamp-Henken. 2014. "Consuming foods with added oligofructose improves stool frequency: a randomised trial in healthy young adults." J Nutr Sci 3:e7. doi: 10.1017/jns.2014.6.

Institute of Medicine, Food and Nutrition Board. 2005. Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids (macronutrients). Washington, DC: National Academy Press.

Also Available in: Español

Publication #FSHN11-01

Release Date:January 1, 2011

Reviewed At:February 1, 2021

Related Experts

Dahl, Wendy J.


University of Florida

Related Topics

Fact Sheet

About this Publication

This document is FSHN11-01, one of a series of the Food Science and Human Nutrition Department, UF/IFAS Extension. Original publication date January 2011. Revised October 2014, December 2017, and February 2021. Visit the EDIS website at for the currently supported version of this publication.

About the Authors

Wendy J. Dahl, PhD, associate professor, Food Science and Human Nutrition Department; UF/IFAS Extension; Gainesville 32611.


  • Wendy Dahl