A fiber supplement is a powder, capsule, or gummy that provides the fiber necessary to compensate for today’s high-carb, low-fiber diets.
Fiber does more than just prevent constipation and diarrhea. Studies show it can also modulate blood sugar, lower blood pressure, reduce cholesterol, and prevent the development of certain types of cancer.
We researched more than 100 popular fiber supplements and concluded that the following represent the best fiber supplements of 2023.
1. NOW Supplements Psyllium Husk Powder
That NOW would produce an outstanding fiber supplement should be no surprise. They’ve been providing a variety of high-quality supplements since 1968. Their Psyllium Husk Powder is clean, simple, and very effective.
What we like: NOW Psyllium Husk Powder is rigorously tested at every phase of production to ensure no genetically modified organisms find their way in. Each serving contains 6 grams of organic psyllium husk powder. That’s it.
Flaws: If we had to nitpick, we might say there are too many carbs for keto dieters.
2. Metamucil Psyllium Husk Capsules
Metamucil makes some of the most popular fiber supplements ever created. They have decades of experience and a spotless reputation for quality and efficacy. Their Psyllium Husk Capsules are a convenient way to get the added fiber you need.
What we like: The size of each capsule is kept modest (2 grams) because the product is intended to be used by kids as young as 12. These are low-carb, low-calorie, sodium-free capsules that will work with just about anyone’s diet.
Flaws: Taking five capsules per day as directed might be too much for some folks.
3. Kirkland Signature Optifiber
Kirkland Signature Optifiber contains wheat dextrin, which is derived from wheat starch and is highly regarded by health professionals for its ability to reduce cholesterol and promote a healthy gut biome.
What we like: Wheat dextrin often gets lost in the shadow of psyllium husk, and that’s a shame because many dieticians consider it just as effective. Kirkland Signature Optifiber wheat dextrin is sugar, lactose and gluten-free, and easy to drink.
Flaws: You need to stir it really well when adding it to a cold beverage.
4. Viva Naturals Organic Psyllium Husk Powder
Viva Naturals Organic Psyllium Husk Powder is certified organic, gluten-free, and vegan. It’s pure psyllium husk ground to perfection, and you don’t need to take it four or five times a day. Once or twice should do it for most people.
What we like: This is a simple, pure product composed of psyllium husk and nothing else. Not even a dash of salt or sugar. Just GMO-free organic psyllium. Take it with eight ounces of water for maximum effect.
Flaws: It works, but does not mix as well as some others.
5. Garden of Life Super Seed
Garden of Life Super Seed is derived from organic flaxseed, chia seed, and about a dozen other high-fiber ingredients chosen for their nutritional value. Super Seed is also rich in probiotics for restoring and maintaining a healthy digestive tract.
What we like: This is one of the most comprehensive fiber-rich ingredient lists you will find. As an added bonus, each serving contains 66 mg of calcium. Super Seed is an outstanding source of both soluble and insoluble fiber.
Flaws: Thickens up pretty quickly after mixing.
6. Swanson Tri-Fiber Complex
Swanson Tri-Fiber Complex is a sound choice for people on the go. Not everyone has the time or the opportunity to stop and mix a glass of fiber powder. For those folks, an easy to swallow, high-fiber, gluten-free capsule like this can be a life saver.
What we like: Swanson Tri-Fiber contains equal amounts of psyllium husk and oat bran fiber, along with a smattering of highly beneficial apple pectin. But don’t worry, there’s no sucrose in that apple pectin. Only fiber.
Flaws: Need to drink a lot of water or it won’t be so effective.
7. Phillips’ Fiber Good Gummies
Sometimes you don’t want to be bothered with mixing fiber powder in a glass or taking a big capsule. But you still need your fiber. In those cases, Phillips’ Fiber Good Gummies are an ideal choice. They have a light, natural taste and melt in your mouth while you chew.
What we like: Phillips’s Fiber Good Gummies contain inulin, which doubles as both a fiber and as a prebiotic that helps maintain a healthy gut microbiome. They can be used by kids as young as four too.
Flaws: They use animal-derived gelatin so vegans beware.
8. Nestle NutriSource Fiber
Each scoop of Nestle NutriSource Fiber provides 3 grams of little-known guar gum fiber to restore a healthy gut environment and keep things moving in a timely fashion.
What we like: Guar gum fiber does not get the kind of press that psyllium does. Nonetheless, it is prized by those in the know for its ability to absorb excess liquids and correct diarrhea and soften stools and alleviate constipation.
Flaws: Tends to sell out fast.
9. Navitas Organics Chia Seeds
Whole chia seeds are 40% fiber, which makes them an excellent fiber supplement. Navitas Organics Chia Seeds are certified Kosher, organic, vegan, and GMO-free. They’re also gluten-free and contain zero sodium.
What we like: This is not a powder. These are whole seeds that can be added to salads, dips, baked goods, and more and will provide the fiber you need along with calcium, magnesium, and iron.
Flaws: They need to be hydrated before using.
10. Heather’s Tummy Fiber
Heather’s Tummy Fiber is 100% acacia senegal fiber. Acacia senegal is a whole soluble fiber that is also an effective prebiotic. So not only will things get moving in your digestive tract, but that digestive tract will be more efficient than ever.
What we like: Heather’s Tummy is likely a very happy place because the acacia senegal fiber is a great source of prebiotics. As such, it’s more than your standard fiber supplement. It can also help in dealing with nutritional shortfalls, IBS, and more.
Flaws: The new packaging is kind of flimsy.
Who Needs A Fiber Supplement?
Everyone needs fiber to maintain a healthy gut microbiome and to ensure food and waste move through the digestive system in a timely fashion. Unfortunately, researchers believe that only about 5% of Americans are getting as much fiber as they actually need (1). This results in millions of people every year suffering from constipation and nutrient deficiencies.
Of course, if you already eat a diet that includes plenty of leafy greens and other forms of dietary fiber, then in all likelihood, you do not need to take a fiber supplement. But you would be the exception. For most of us, we have two choices: either increase the amount of dietary fiber we get from the food we eat, or take a fiber supplement.
How We Ranked
There are a lot of supplements and other products on the market right now that claim to be high in fiber. But we are only interested in those specifically designed to deliver high-quality fiber for the purposes of achieving and maintaining a healthy digestive tract and promoting regularity.
That means you won’t find things such as high fiber protein powders on our list. Because they are formulated to address the needs of the bodybuilder, of which adequate fiber is only one. Using such a product strictly for the fiber, without engaging in rigorous strength training, would likely produce little besides enormous love handles.
The type of fiber was also important. Psyllium is generally considered to be the gold standard of fibers because it is pure and simple and gluten-free and known to be highly effective for most people. But there are other types of fiber that are also safe and effective, such as chia seeds, wheat dextrin, and more. So our list is not confined to psyllium.
We also wanted to include a range of delivery methods, which means fiber capsules, gummies, and powders, simply because not everyone’s preferences are the same. Powders, however, needed to be free of artificial flavors, colors, preservatives, and sweeteners. If a sweetener was used, we gave the nod to a natural one like stevia over something like cane sugar.
Finally, we sifted through mountains of user reviews to see if we could identify any positive or negative trends within the feedback. After all, if a thousand people say something works, against only a few who say it does not, that deserves to be considered.
Q: What is fiber?
A: Fiber is a type of food that has little nutritional value but is crucial to proper digestion and to maintaining regular bowel movements. Carbohydrates, fats, and proteins are broken down by the digestive system and the nutrients absorbed to provide energy and facilitate cell production. Not fiber. Insoluble fiber moves through your digestive tract largely untouched. At the same time, soluble fiber is used as fuel by the bacteria in your gut that metabolize nutrients.
Q: Why do I need a fiber supplement?
A: It is recommended that people get between 20 and 35 grams of fiber per day. Exactly how much depends mostly on the size of the person and how much food they eat every day. But as a general rule, it is recommended that the average woman get 25 and the average man 38 grams of fiber per day (2). The problem is, researchers believe the average American only gets 12-15 grams. That is why you probably need a fiber supplement.
Q: How long does it take a fiber supplement to relieve constipation?
A: Some folks only take a fiber supplement when they experience constipation. In such cases, it should take anywhere from 24 to 48 hours for the fiber supplement to relieve constipation. The best approach, however, is to make a fiber supplement a part of your regular dietary intake. That will help keep constipation at bay and deliver the other benefits we listed above.
Q: Is the fiber in supplements the same as the fiber in a salad?
A: Not really. The fiber in something like a salad is provided in its natural state and is able to clean your digestive tract a bit more effectively as a result. Also, if you are eating salads and other high fiber foods, you probably are not eating much junk food, which is obviously a good thing. That said, the differences between natural fiber and fiber supplements are not substantial, and fiber supplements are a far superior option to not getting any fiber.
Q: What is psyllium?
A: ‘Psyllium’ or ‘psyllium husk’ are words you will read and hear a lot when researching fiber supplements. Psyllium sounds like something used to make nuclear weapons, but in fact, it is the name of a fairly unremarkable type of plant whose seeds are prized for the high fiber content of their husks. Psyllium is great for relieving constipation and diarrhea (3) and is one of the most common ingredients in commercial fiber supplements.
Q: Can I take a fiber supplement every day?
A: Yes, you can safely take a fiber supplement every day. There is no evidence that fiber supplements produce adverse effects when taken regularly. In fact, the opposite is true. Fiber supplements can also be taken occasionally if you are suffering from constipation or diarrhea. Although the best approach is to take fiber every day in order to prevent constipation or diarrhea from happening in the first place.
Q: I am not eating excessive amounts of fiber, why am I gassy?
A: Flatulence is often the result of consuming more fiber than you need. But in some cases, people will experience gas even when they adhere to the recommended dosage. When this happens, it is usually because a person is just starting out with a fiber supplement. Their body just needs time to adjust to the new normal. Given time, it should eventually settle down. If the gassiness does not subside, try a different supplement.
Q: What are prebiotics?
A: ’Prebiotic’ is another name for soluble fiber. This type of fiber is used as fuel by the live bacteria in a person’s gut. That may not sound like such a good thing, but the gut is full of beneficial bacteria called ‘probiotics’ (4) that play a crucial role in the digestive process. Without them, a person would essentially starve to death because they would not be absorbing enough nutrients from the food they eat.
Q: Are there any side effects to fiber supplements?
A: When taken as directed fiber supplements typically produce few if any side effects. People who take more than the recommended amount will likely experience bloating or gas, or both. Some will experience diarrhea as the excess fiber is continually moving through their digestive tract. Also, taking too much fiber may result in a shortage of some minerals, as they bind with the fiber and are evacuated during bowel movements.
Q: Are fiber supplements gluten-free?
A: When people adopt a gluten-free diet they also, often inadvertently, adopt a low-fiber diet. That’s because many of the foods that contain gluten are also high in fiber (such as bread, crackers, and cereal). Giving up these foods can produce a significant fiber shortage. Fortunately, you can make up for that shortage with fiber supplements. And most fiber supplements, including psyllium, are gluten-free. Always check the label anyway, just to be sure.
Q: Do fiber supplements contain sugar?
A: No, most fiber supplements are completely devoid of sugar. Some may contain trace amounts of sucrose, if fruits are used as part of the ingredient list. But this is rare. Most fiber supplements contain no naturally occurring or added sugar.
Q: How can fiber help a person lose weight?
A: When you take a fiber supplement, you need to drink plenty of water with it. That water causes the fiber to swell in your digestive tract. That has two effects. First, the swollen fiber takes up space in your gut, producing a feeling of being full, which should help you eat less. And second, fiber is slow to digest, so that sensation of being full tends to linger, preventing most people from wanting to eat as often.
Q: Can fiber really reduce my chance of getting cancer?
A: This seems like a far-fetched marketing claim, but there is ample science to back it up (5). Researchers have known for years that getting enough fiber will reduce the odds of developing colon cancer. But recent large scale studies indicate getting enough fiber in early adulthood may also reduce the risk of developing breast cancer (6). Additional studies are even suggesting fiber may play a role in preventing other types of cancer as well.
Q: Can fiber supplements cause dehydration?
A: They may if you do not drink enough water when taking them. Soluble fiber is very absorbent. So, as a general rule, it is recommended you drink at least one full glass of water when you take a fiber supplement (consult the label on the particular supplement you have to determine exactly how much water to drink). Failing to drink enough water can cause stomach pain as the fiber soaks up what little moisture there is in your digestive tract.
Q: Do fiber supplements interfere with medications?
A: In most cases fiber supplements will not interfere with medications. There are a few exceptions to that rule, however. A fiber supplement may interfere with how aspirin or NSAIDs are absorbed. So you should not take the two things one right after another. Also, because fiber has an impact on both blood glucose and blood pressure levels, you should talk to your doctor before taking fiber supplements if you are being treated for either of those.
Q: Can a fiber supplement lower my cholesterol levels?
A: Yes, a fiber supplement can help lower your cholesterol levels. Numerous health studies over the years have confirmed this. And the US government’s National Library of Medicine recommends people consume more fiber (7) in order to lower the amount of ‘bad’ LDL cholesterol in their system.
Q: What is the best time to take fiber supplements?
A: In most cases, there is no ‘best time’ to take a fiber supplement. That said, if it is recommended you take a particular supplement three times per day, then you will want to spread the doses out and not want to bunch them all together. As we mentioned above, you probably should avoid taking fiber supplements and things like aspirin at that same time too. And, most importantly, always remember to drink enough water when taking fiber supplements.
Q: Can pregnant women take fiber supplements?
A: Yes, pregnant women can and often should take fiber supplements. Constipation is an all-too-familiar problem encountered by pregnant women. Fiber supplements can be a convenient, effective way to either fend off constipation (if taken regularly) or relieve constipation (if taken after the constipation manifests). Psyllium husk fiber supplements are considered a good choice for pregnant women (8).
Q: Are fiber supplements vegan?
A: Some fiber supplements are vegan and some are not. In large part, it depends on the form the supplement takes. Powder supplements that are mixed with water are likely to be void of all animal products (although they may be processed in a facility that also processes animal products for other uses). Gelcaps, however, are sometimes made using bovine gelatin. You will need to check the label carefully before choosing a fiber capsule.
Fiber supplements fill an essential role in helping Americans get the fiber many of them are sorely lacking. But fiber supplements do more than just help a person get and stay regular. They also help reduce cholesterol and blood pressure levels, stabilize blood sugars, prevent certain types of cancer, and much more.
Fiber supplements come in several forms, so there is bound to be one that you find agreeable. Use the above information to determine which fiber supplement is just right for you.
For cpoe.org’s #1 recommended fiber supplement, click here.