Digestive Health Inflammatory Bowel Disease Nutrition The Health Benefits of Fiber Supplements Help with Constipation, Diarrhea, IBS, IBD, and Diverticulosis By Amber J. Tresca facebook twitter linkedin Amber J. Tresca is a freelance writer and speaker who covers digestive conditions, including IBD. She was diagnosed with ulcerative colitis at age 16. Learn about our editorial process Amber J. Tresca Fact checked by Fact checked by Lisa Sullivan, MS on April 18, 2020 Lisa Sullivan, MS, is a nutritionist and a corporate health and wellness educator with nearly 20 years of experience in the healthcare industry. Learn about our editorial process Lisa Sullivan, MS on April 18, 2020 Print Table of Contents View All Table of Contents Health Benefits Possible Side Effects Dosage and Preparation What to Look For Other Questions Fiber supplements are nutritional products that are available over the counter at drugstores, health food stores, and big box stores, as well as online. They come in a variety of formulations, including capsules, powders, and baked goods and contain one of three types of fiber—psyllium, methylcellulose, or polycarbophil. Fiber supplements typically are taken to help maintain healthy functioning of the digestive system, aid in weight loss, and help treat or prevent certain diseases and conditions. They generally are regarded as safe but some fiber supplements can cause side effects, such as bloating or gas, if not taken according to directions. Roel Smart / E+ / Getty Images Health Benefits Fiber is a type of carbohydrate that occurs naturally in fruits, vegetables, legumes, and whole grains. Despite being so plentiful, most Americans do not eat enough of the foods that naturally contain fiber. Supplements can help people to enjoy the many health benefits of fiber, which include helping to maintain optimal blood sugar and cholesterol levels. Adequate fiber intake also is associated with preventing certain cancers, heart disease, diabetes, and food allergies. For optimal health, the Academy of Nutrition and Dietetics recommends adult men get at least 38 grams (g) of fiber per day and women get 25 g of fiber per day. Most often, people take fiber supplements to help manage certain digestive problems. Soluble fiber absorbs water as it passes through the digestive tract, transforming into a gel-like substance that helps slow digestion, making it especially useful for treating diarrhea. Insoluble fiber softens and adds bulk to stool so that it's easier to pass, and therefore can help relieve constipation, as well as prevent hemorrhoids and anal fissures that can result from passing hard stools. Adequate fiber also is important for maintaining regular bowel movements. Fiber is filling and can be helpful for weight loss and maintenance. Fiber supplements are sometimes included as part of an overall treatment plan for conditions such as irritable bowel syndrome (IBS), inflammatory bowel diseases (IBD) including Crohn's disease and ulcerative colitis, and diverticulosis. They should be used only with a doctor's direction in these circumstances. Possible Side Effects The potential side effects of fiber supplements include: Gas and pain from gasAbdominal bloatingLowered blood glucoseDiarrhea or constipation (if taken in excess)Unwanted weight loss Because of the way fiber supplements bulk up in the intestinal tract and absorb surrounding materials, they can interfere with the body's ability to assimilate medications, vitamins, and nutrients. Dosage and Preparation Fiber supplements come in a variety of formulations, including powders to be mixed with water or another liquid, capsules to be swallowed whole, and added to foods like crackers, cookies, cereals, and bars. Dosage will vary based on the product and the desired effects. It's generally advisable to start with a low dose of fiber and build up until you've reached the recommended total daily fiber intake which should include your dietary sources of fiber, as mentioned below. Psyllium Made from the seeds of a plant in the Plantago genus, psyllium contains 70% soluble fiber and 30% insoluble fiber. It breaks down in the gut (fermentation) as a food source for the "good bacteria." For this reason, it can cause gas. Psyllium is used to treat constipation, irritable bowel syndrome (IBS), and diverticulosis. It has roughly 20 calories per tablespoon. Brand names include Metamucil, Fiberall, Hydrocil, Konsyl, and Serutan. Methylcellulose This non-allergenic, non-fermentable fiber is created from the cell walls of plants. It's a soluble fiber that pulls in water to create a softer stool and often is used to treat constipation and some causes of diarrhea, and maintain regular bowel movements. It can be used long term but may interfere with absorption of food and nutrients and so should not be taken at the same time as some prescription medications. Methylcellulose is sold under the brand name Citrucel. Polycarbophil Similar to methylcellulose, this soluble fiber also absorbs water in the intestinal tract and creates a bulkier, softer stool. It does not ferment and is not absorbed by the body. Polycarbophil may be used to treat constipation and bowel movement irregularities, but is not appropriate for people who have difficulty swallowing. It should not be taken at the same time as medication. Polycarbophil is sold under the brand names FiberCon, Fiber Lax, Equalactin, and Mitrolan. What to Look For When shopping for fiber supplements, you'll want to make sure it contains the type of fiber you want. And some supplements have added sugar, salt, flavorings, or dyes you may want to avoid. For these reasons, make sure to check the ingredients listed on the packaging before making your purchase. Other Questions What are the best dietary sources of fiber? Whether or not you choose to supplement with fiber, it's important to include a variety of fiber-rich foods in your diet, such as: Fresh fruit (e.g., pears, apples, strawberries, bananas)Fresh vegetables (e.g., broccoli, Brussels sprouts, beets, and carrots)Legumes (e.g., lentils, split peas, kidney beans, chickpeas, black beans, pinto beans)Whole grains (e.g., quinoa, oats, brown rice, millet, barley, farro)Other sources (e.g., popcorn, cereal, chia seeds, flax seeds) Is it a good idea to take a fiber supplement every day? There is no evidence to suggest that taking daily fiber supplements is harmful and many people do make it part of their everyday health regimen. What time of day is best? Recommendations for when and how frequently to take fiber supplements vary. You may want to divide your daily dose into two or three portions to reduce bloating and gas that could occur when taking a large dose all at once. To avoid malabsorption, it's important to take medications or vitamins either one hour before, or two hours after taking fiber supplements. If using a powdered form of fiber, dissolve it well. Always drink plenty of water when taking fiber supplements. A Word From Verywell Fiber supplements are available over the counter and are considered safe for most people. If you have a medical condition you think might improve by taking a fiber supplement, though, talk to your doctor first. If you are experiencing diarrhea or constipation regularly, you may need to be evaluated for a digestive condition before starting to treat it with fiber. Was this page helpful? Thanks for your feedback! We're providing tips on how to take better care of your gut. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Liu L, Wang S, Liu J. Fiber consumption and all-cause, cardiovascular, and cancer mortalities: A systematic review and meta-analysis of cohort studies. Mol Nutr Food Res. 2015;59(1):139-46. doi:10.1002/mnfr.201400449 Academy of Nutrition and Dietetics. Fiber. November 2018. MedlinePlus. Soluble vs. insoluble fiber. Updated April 9, 2020. Lyon M, Kacinik V. Is there a place for dietary fiber supplements in weight management? Curr Obes Rep. 2012;1(2):59-67. doi:10.1007/s13679-012-0016-9 Drugs.com. Fiber capsules side effects. Updated February 14, 2020. McRorie J. Evidence-based approach to fiber supplements and clinically meaningful health benefits, part 1. Nutr Today. 2015;50(2):82-89. doi:10.1097/nt.0000000000000082 Jalanka J, Major G, Murray K et al. The effect of psyllium husk on intestinal microbiota in constipated patients and healthy controls. Int J Mol Sci. 2019;20(2):433. doi:10.3390/ijms20020433 Drugs.com. Citrucel (methylcellulose) drug interactions. Updated April 2020. American Family Physician. Management of constipation in older adults. September 2015. Drugs.com. Polycarbophil. Updated September 9, 2019. Lambeau KV, McRorie JW Jr. Fiber supplements and clinically proven health benefits: How to recognize and recommend an effective fiber therapy. J Am Assoc Nurse Pract. 2017;29(4):216–223. doi:10.1002/2327-6924.12447