Everything you need to know about fiber supplements so that you can choose the right product for you! It can be quite confusing with so many options available, but it all comes down to this: what is your main goal for supplementing fiber?
Of course, meeting your fiber needs from foods is most ideal, but most Americans are not even close to doing so. Since it is super hard to meet your dietary fiber needs for the day, I do believe that fiber supplementation along with a healthy diet can help fill in those gaps!
However, there is little public awareness about the different types of fiber, what they do, and how they impact the body differently. Most people hear “fiber supplement” and immediately think of Metamucil.
Even as a dietitian, I get confused sometimes. So, let’s break it down with supplement reviews and recommendations to hopefully help you decide which one works for you so you don’t waste your money!
Why Fiber is So Important
Most Americans are not meeting the recommended fiber needs, which is included in the dietary guidelines because it is so important for overall health. Consuming the recommended 25-38 grams of fiber per day can:
- Improve digestion and regularity.
- Support healthy weight management by increasing meal satiety and keeping us fuller for longer.
- Promote more balanced blood sugar.
- Support heart health and lower cholesterol.
- Help prevent certain cancers, like colon cancer.
Forget Soluble vs. Insoluble
There seems to be this categorization of fiber as either soluble (dissolves in water) or insoluble (does not dissolve in water). However, I have come to find out it is so much more nuanced than that.
The effects of fiber depend more on:
- Gel-forming (viscosity): slows digestion, helps regulate blood sugar & cholesterol.
- Fermentable (prebiotic): feeds gut bacteria → better digestion, immunity, even mood.
- Bulking: adds mass to stool, keeps things moving smoothly.
Most fibers do one or two, some do all three. The ones that do all three, though, may not do them as well as other types.
A little more nuance.
In a nutshell, insoluble fiber decreases digestion time – bulking up and softening stools which makes them easier to pass. This increased transit time may reduce weight gain because less energy is absorbed during digestion.
These studies, found mostly in mice, have shown insoluble fiber may contribute to weight loss because the speed in which food is digested increases, and therefore, we don’t absorb as many calories.
Therefore, the primary benefits of insoluble fiber are weight loss and digestive health.
On the other hand, soluble fiber can contribute to both constipation and diarrhea, meal satiety, weight loss, improved gut health, lower cholesterol, metabolic health, immune support and more.
There is a whole category of prebiotic fibers that go through a fermentation process in the gut, which is very beneficial for gut health. These types of soluble fiber are fermented in the large intestine, producing glucagon-like peptide (GLP-1) and peptide YY (PYY) – two hormones which increase satiety or those feelings of fullness.
One of the main benefits of prebiotic fiber is that it feeds the beneficial bacteria in your gut, helping them grow and thrive. These “good bugs” play a major role in everything from digestion to mood and hormone balance.
For this reason, there are definitely more soluble fiber supplements than insoluble fiber. However, both types of fiber are important for overall health and digestion (but for different reasons).
Questions to Ask When Choosing a Supplement:
- What is your goal in taking a supplement? Overall health, constipation, blood sugar management, cholesterol, gut health?
- Do you have bloating or gas when consuming a higher fiber diet? Start with a lower dose and gradually increase OR try low FODMAP type of fiber.
- Need bulk? Psyllium is often most effective and most researched.
- Form: do you prefer powder, capsules or gummies?
- Is it third-party tested, especially by reputable third parties like USP and NSF?
Since there really isn’t a fiber supplement that can “do it all”, aim to consume a diet rich in the type of fiber you might not bet getting enough of. For example, if you take a psyllium fiber supplement then you might want to consume foods with resistant starch!
Top Fiber Supplement Recommendations
This section goes over different types of fiber supplements.
This article does include some Amazon affiliate links. I receive a small compensation if a purchase is made – I highly recommend only buying straight from the company and not a third-party.
Inulin
Inulin is the type of fiber found in the popular prebiotic soda, Poppi. It is a highly fermentable, prebiotic fiber. You can find inulin from onions, chicory root, Jerusalem artichokes, onions, garlic, leeks, and asparagus.
Great for:
- Improving the composition of our gut. It is one of the best types of prebiotic fiber and feeds the healthy gut bacteria.
- Due to the potential to improve gut health, you might see all the other benefits of a more diverse and healthy gut like immune support and improved mental health.
- Some research shows it could stimulate production of GLP-1.
Potential Disadvantages:
- Often causes bloating and gas, especially at higher doses.
- It is not tolerated as well as other types of fiber. You may need to experiement and do a “ramp up” period where you start low and go slow.
- If you have IBS, you may not tolerate it at all.
Supplements to Try:
- NOW Inulin Powder: budget-friendly, one of my favorite brands, highly rated, and third-party tested.
- It’s Just! Inulin Prebiotic Powder
- Or, try a combination: Metamucil Prebiotic Fiber Supplement with inulin and fibersol, which supports healthy digestion.
Psyllium Husk
Psyllium husk is one of the most well-researched and affordable types of soluble fiber. Most specifically, psyllium helps lower cholesterol and improve metabolic health.
Why it’s a good option:
- Effective
- A lot of research to back up the benefits
- Great for overall heart health, lowering LDL cholesterol and regular bowel movements.
- Less loose stools and increased bowel regularity.
- It is more gentle on the gut! May be tolerated by those with IBS, specifically IBS-C.
Potential Disadvantages:
- Not quite as fermentable as other soluble fibers, like inulin or wheat dextrin.
Supplements to Try:
- Metamucil – usually comes in a powder to mix in water – which actually is very helpful since drinking a lot of water is recommended when consuming fiber.
- NOW Psyllium Husk Powder
Wheat Dextrin
Wheat dextrin is the type of fiber found in the very popular Benefiber. It is a fermentable fiber that offers mild prebiotic support.
Great for:
- Nourishing the growth of good bacteria that exists in your gut as it is a prebiotic fiber.
- Managing hunger and increasing fullness. Studies show it may assist with weight maintenance and satiety.
- Less likely to cause gas than inulin or FOS, but not as gentle as PHGG.
Disadvantages:
- It won’t bulk stool as strongly as psyllium or methylcellulose, but it may help improve stool frequency and feed gut bacteria.
- Not much research on this type of fiber and IBS.
Supplements to Try:
- Benefiber Prebiotic Fiber, best to consume 2-3 times per day.
Beta-Glucans
Beta-glucans, found in foods like oats and barley, are most notable for lowering bad LDL cholesterol and reducing the risk of coronary heart disease and type 2 diabetes. Use caution if you have celiac disease or are gluten intolerant.
Great for:
- Well-known benefits, like lower LDL cholesterol, improved insulin sensitivity and blood sugar response.
- Supports immune function.
Why it might not be the best option:
- Beta-glucans are found in a lot of common foods – so you could just consume those foods instead!
- Low fermentability → not a strong prebiotic.
- Not the best option for bulking stool.
Supplements to Try:
Methylcellulose
Methylcellulose is a soluble bulk-forming laxative primarily used to treat constipation.
Great for:
- Bowel regularity.
- Doesn’t cause excess gas, as it is not a fermentable type if fiber.
Disadvantages:
- Not low FODMAP – more likely to cause digestive discomfort as compared to psyllium.
- Trace amounts of gluten are often found in these supplements.
- Not as effective as psyllium at lowering cholesterol.
- Lacks fermentability and therefore doesn’t support gut nourishment.
Supplements to Try:
Resistant Starch
Resistant starch is a highly fermentable type of fiber that is great for short-chain fatty acid production. It is naturally found in foods like green bananas, cooked-and-cooled potatoes or rice, lentils, and oats.
It’s gaining attention as a natural gut + metabolic health booster.
Why it might be a good option:
- Stimulate short-chain fatty acids, which also directly increases the production of GLP-1 and helps improve the composition of the gut.
- May help manage weight by increasing fullness.
- May help control blood sugars, increases insulin sensitivity, and may reduce the risk of diabetes.
- It is slowly fermented in the large intestine. This gradual release of gas does not result in the same degree of gas and discomfort as with FODMAPs.
Disadvantages:
- It is not particularly bulking or gel-forming, so not the best choice for improving bowel regularity.
- Appropriate dosage is unclear but definitely a promising area of future research.
Supplement to Try:
- Dr. Mercola Resistant Starch Complex with 3 types of resistant starch.
PHGG or Partially Hydrolyzed Guar Gum
Partially hydrolyzed guar gum (PHGG) is a soluble fiber extracted from the seeds of the guar bean. There are many benefits to PHGG and it’s the one you want to choose if you have a very hard time tolerating fiber.
What the pros are:
- Is a prebiotic fiber, can feed the good bacteria in the gut.
- Potentially stimulating natural production of GLP-1.
- Can help both diarrhea and constipation.
- Great for those with IBS, sensitive tummies or following a low FODMAP diet.
What it’s lacking:
- More research is needed. One study in mice found that supplementation exacerbated symptoms of colitis.
Supplements to Try:
- Tomorrow’s Nutrition SunFiber
- Benefiber Advanced Digestive Support (also contains probiotics, too)
Combination Fiber Supplements
If choosing just one fiber feels overwhelming, combination supplements can seem like a good solution. They often blend several types to offer multiple benefits – like improving regularity and providing prebiotic fiber as well.
However, the biggest downfall is that they are extremely expensive. Let’s go over a few.
Are they the way to go?
If you’re new to fiber or have a sensitive digestive system, it may be better to start with a single-source fiber like psyllium, PHGG, or acacia and see how your body responds.
May be harder to tolerate.
Many blends include multiple fermentable fibers (like inulin, FOS, and resistant starch) which ferment rapidly in the gut and can lead to gas, bloating, or cramping.
May have less fiber.
Some of these combination supplements have less fiber per serving.
Seeds DS-01 Prebiotic + Probiotic
This is a combination supplement with a prebiotic fiber plus live, active probiotics. The supplement promises bowel regularity, immune support, skin and heart health.
- What is in it: combines gut microbiome support (prebiotic from pomegranate fruit + probiotic in one).
- Pros: good clinical backing, well-formulated, gentle on the gut, special capsule helps the live bacteria make it to the small intestine.
- Cons: very expensive, not really a “fiber supplement” in the traditional sense
Sunfiber GI
This is a similar product with both prebiotics and probotics but a lot cheaper (and only one probiotic strain).
- What’s in it: PHGG (sunfiber) plus bifidobacterium lactis
- Best for: general digestive health, occasional constipation, improving the gut microbiome
Regular Girl Prebiotic Fiber and Probiotic Blend
A low FODMAP friendly choice for those wanting to take a probiotic supplement too.
- What’s in it: 6 grams of sunfiber/PHGG + probiotic strain Bifidobacterium lactis.
- Why it’s great: combines gut-friendly fiber and probiotic in a very gentle formula.
- Cons: expensive, can consume probiotics from food sources like kefir and kombucha. Only has one probiotic strain.
Yerba Prime Prebiotic Colon Care
Best for those who want fiber for both regularity and microbiome support.
- What’s in it: psyllium fiber, acacia gum, oat bran, apple fiber (psyllium + inulin)
- Why it’s great: research-backed psyllium with heart health and blood sugar benefits plus prebiotic fiber than feeds the good bacteria in the gut.
- Cons: may not be well tolerated in those with sensitive stomachs. A trusted brand but not clearly labeled third-party testing.
Garden of Life Raw Organic Fiber
- What is in it: a blend of 15 organic superfoods including soluble, insoluble, and prebiotic fiber. Plus, one probiotic strain and omega-3 ALA.
- Why it’s good: whole-food-based, includes both bulking and fermentable fibers
- Best for: general digestive health, occasional constipation, improving gut microbiome, overall health. This one almost does it all, honestly.
- Potential cons: more calories than the average fiber supplement. Does not have psyllium, which is well-known for the heart health benefits.
I hope this supplement guide helped you figure out which type is right for you! Feel free to follow along for more nutrition content and healthy, well-balanced recipes with protein and fiber.