Fiber Supplements for Digestive Health: What the Science Says

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    Fiber supplements can help with digestive health, including occasional constipation. Read on to learn more.

    Most people experience constipation from time to time. It’s a symptom of other underlying causes – one of which can be a lack of adequate fiber. If occasional constipation has been a problem for you, you might want to talk to your doctor about whether upping your fiber intake can be part of the solution. There are so many fiber-rich foods and supplements to choose from, and we’re here to help you make sure you have all the facts.

    What is fiber?

    Fiber is a carbohydrate that’s indigestible by the body.

    Most carbs are broken down by our bodies into sugar molecules, known as glucose; fiber, on the other hand, goes through the body undigested. Its function is to help our body’s regulate the use of sugars, while managing hunger and blood sugar levels already within normal limits.

    Types of fiber: Soluble vs insoluble fiber

    There are two types of fiber, both of which are beneficial: soluble and insoluble.

    Soluble fiber dissolves in water, and it can help manage glucose levels and promote healthy cholesterol levels that are already within normal limits.

    Insoluble fiber, on the other hand, doesn’t dissolve in water. It helps food move through the digestive system, thereby supporting healthy bowel movements and helping to prevent occasional constipation. If you experience chronic constipation be sure to talk to your doctor as it may be a sign of a more serious underlying condition or issue.

    Furthermore, there are dietary fibers that occur naturally in plants, and there are functional fibers that are extracted from plants or made synthetically. Some fibers fall into both categories. In any event, what unites all the types of fibers is that they are nondigestible and they have health benefits for us.

    Why is fiber important?

    Fiber and its role in occasional constipation

    Fiber, in all its forms, has important benefits for your gastrointestinal system. Studies have consistently demonstrated fiber’s role in promoting digestive health, including occasional diarrhea and constipation. It’s also been shown to be helpful in managing gas and bloating. Some fibers also act as prebiotics, providing sustenance for the good bacteria in your gut and promoting gut health generally.

    Constipation is defined as having three or fewer bowel movements over the course of a week. We all experience constipation from time to time. When it becomes too frequent, though, it can lead to other health problems sobe sure to communicate chronic health concerns with your healthcare provider.

    Soluble fiber can absorb water and add bulk to your stools, thus making sure that your bowel movements stay healthy and regular. Insoluble fiber helps your food pass through the digestive system with greater ease, which can also prevent constipation.

    For people experiencing constipation, doctors and dietitians will often recommend eating fiber-rich foods or taking fiber supplements. They will also recommend maintaining proper hydration, as well as getting adequate sleep and exercise.

    Care/of offers a comprehensive (and fiber-rich) Gut Musts package, which includes prebiotics, digestive enzymes, chia-flax, and probiotics.

    How much fiber should you have in a day?

    Most Americans only get half the level of fiber they require. The recommended daily allowance of fiber for women is 25 grams of fiber per day. Men require 38 grams of fiber per day.

    Excess amounts of fiber can result in some digestive discomfort, so it’s important to be cautious about fiber intake and supplementation. Talk to your doctor about how much you need. Some studies suggest that fiber intake above 70 grams can cause discomfort as your gut microbiome tries to adjust.

    Food sources of fiber

    Fortunately, there are many great food sources of fiber.

    Some foods with soluble fiber include oatmeal, nuts, chia seeds, beans, lentils, apples, and blueberries. Some foods with insoluble fiber include quinoa, legumes, brown rice, leafy greens (think of kale), almonds, seeds, walnuts, and fruits with edible skins (pears and apples, for example). Most root vegetables are sources of fiber.

    What to look for in fiber supplementation

    When considering fiber supplementation, you’ll likely notice how many types of fiber supplements are available to you. Don’t fret. We’ll help you know what to consider as you make your selection. The three most important factors are: ingredients, dosaging, third-party testing.


    Some supplements, including fiber supplements, may include ingredients that you’re sensitive to. Be sure to check the label to see the full list of ingredients included. Consult your doctor if you have any questions.


    Getting the right dose of fiber – indeed, of any supplement – is essential to the success of that supplement in addressing your particular needs. A doctor or dietitian can help you figure precisely what your needs are and point you in the right direction. Taking too much fiber or too much too quickly can sometimes lead to some temporary gastrointestinal issues, including bloating and general discomfort while your body adjusts.

    So, here are some basic rules of thumb: Talk to your doctor and follow the recommendations on the label. Always make sure to stay hydrated, too! If some digestive discomfort does occur, try a smaller dose and gradually increase over time, as needed.

    Third-party testing

    Third-party testing is when dietary supplements are tested by an outside organization to determine whether the supplement is of high quality. Reputable, established supplement manufacturers routinely use third-party testers to assure consumers of the quality of the products. When selecting a fiber supplement, look for a third-party verification on the label. All Care/of supplements are third-party tested.

    Potential side effects

    Fiber has a number of health benefits, including supporting the digestive system by increasing stool bulk, frequency, and reducing intestinal transit time in healthy individuals. It's best to get fiber from food so you also get the vitamins, minerals, and other nutrients that fiber-rich foods contain. But fiber supplements can also contribute to the recommended daily intake.

    Fiber supplements can cause abdominal bloating and gas, at least initially. If you have intestinal issues, talk to your doctor before adding a fiber supplement to your diet. It's also a good idea to ask your doctor or pharmacist whether fiber supplements interact with any medications you take.

    Who might not benefit from fiber supplementation?

    People with certain digestive issues should avoid fiber supplementation, since it can aggravate existing symptoms. Consuming excess fiber can lead to gastrointestinal problems, including bloating, gas, and other forms of digestive discomfort.

    Final takeaways

    Fiber is a carbohydrate that your body can’t digest. The two forms of fiber are: soluble (dissolves in water) and insoluble (doesn’t dissolve in water). Both forms are important for your gastrointestinal health and both can promote healthy bowel movements. Insoluble fiber helps with intestinal transit time by helping food pass through your digestive system with greater ease. Soluble fiber helps by adding bulk to your stools and helping your bowel movements pass easily and consistently.

    The recommended intake of fiber for women is 25 grams per day, and for men it’s 38 grams per day.

    If occasional constipation is a problem for you, you should talk to a doctor about whether low fiber intake is to blame. A well-chosen fiber supplement can help promote a healthy digestive system. When selecting a fiber supplement, be sure to examine ingredients, dosaging, and whether the supplement has been third-party tested.

    Care/of offers a number of excellent (and third-party tested!) supplements that can boost digestive health and relieve occasional bloating. Check out our Gut Musts package, for example, or any of the following: chia-flax, prebiotics, probiotics, and digestive enzymes.

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    Dr. Carla Montrond Correia ND, CNS
    Medical Content Manager
    Dr. Montrond-Correia is a licensed naturopathic physician and a certified nutrition specialist (CNS). She holds degrees from University of Bridgeport, Georgetown University, and University of Saint Joseph, and supplemented her education with internships in the health and wellness space. She's focused on research, herbal medicine, nutrigenomics, and integrative and functional medicine. She makes time for exercise, artistic activities, and enjoying delicious food.
    Our Editorial Staff
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    The Care/of Editorial Team is made up of writers, experts, and health enthusiasts, all dedicated to giving you the information you need today. Our team is here to answer your biggest wellness questions, read the studies for you, and introduce you to your new favorite product, staying up to date on the latest research, trends, and science. Each article is written by one of our experts, reviewed both for editorial standards by an editor and medical standards by one of our naturopathic doctors, and updated regularly as new information becomes available.