Which Fiber Supplement is Meant for You?

Meeting your fiber needs can feel like a lofty goal, especially when navigating a busy schedule, traveling and dining out. Cue fiber supplements, a convenient way to make sure you don’t miss a beat in meeting your fiber goal. But does your fiber supplement forego your need to focus on fiber in your diet? Not necessarily. Although fiber supplements can be quite beneficial for more than one aspect of your health, meeting your fiber goal through a variety of options is recommended to best support your microbiome. Fiber supplements are a great way to fill in the gaps in your diet and provide consistency in your routine.

Fiber supplements can be a healthy tool used to achieve specific health goals such as lowering cholesterol or improving digestive health. Knowing which fiber supplement to choose can be difficult to navigate on your own. Not only do you need to consider your personal health goals, but you must also consider the quality of the product. In this article, we will evaluate the function of different types of fiber and list corresponding supplement options so you can feel confident in your fiber supplement regimen.

Viscous Fiber

Viscous fiber is a type of soluble fiber which has a thick, sticky consistency. Its gel-like texture is the key reason for its numerous health benefits. Viscous fiber, commonly found as “psyllium husk” in supplements, is often the first option recommended by providers. One of the established benefits of psyllium husk is its ability to decrease low-density lipoprotein or LDL cholesterol. Products containing at least 7 g of soluble fiber from psyllium husk have been approved by the U.S. Food and Drug Administration  to help lower LDL cholesterol. Studies show these supplements alone can lower LDL-C anywhere from 3-7%. Psyllium husk supplements are also an ideal option for those aiming to:

• Improve their blood sugar control
• Regulate their digestion
• Even aid in their weight loss journey by managing appetite levels

Because this supplement has been well-studied and has a multitude of benefits, it can be an excellent option for individuals looking to try a fiber supplement for the first time.

Psyllium husk is not the only type of viscous fiber available. Partially hydrolyzed guar gum, most known as SunFiber®, is another popular viscous fiber supplement on the market. While this supplement can also be beneficial for lowering cholesterol, it differs from psyllium by providing more prebiotic benefit, which helps to feed and nourish the gut microbiome. This prebiotic effect inspires good bacteria to grow and thrive. It’s important to know most fibers are prebiotic, meaning they provide some level of growth to good bacteria in the gut; however, psyllium is the least fermentable of all fiber types. If you are looking for a fiber supplement to benefit your microbiome, psyllium husk may not be the best option for you. This is one reason obtaining a variety of fiber sources, whether through diet and/or supplements, is essential. Remember, viscous fibers can also be found in the foods you eat day to day. Beta-glucan and pectin are two examples of this, with beta-glucan found in oats and pectin present in fruit such as apples.

One of the advantages of taking a fiber supplement is they can be chosen specifically to target an identified health goal. For example, individuals working toward improving digestive health issues such as constipation or diarrhea can use a fiber supplement to increase the isolated fiber type most likely to benefit their symptoms. Psyllium husk can be a good option for regulating both diarrhea and constipation, especially if current dietary fiber intake is not adequate. Before purchasing, look for a third-party certified option to ensure the supplement is both safe and potent. Yerba Prima® and Organic India® psyllium husk are two great examples of this. Metamucil® is another psyllium husk option many people are familiar with, however it is not a top recommendation due to questionable lead content in the product over the years.

Fermentable Fiber

Fermentable fiber is a type of soluble fiber that is broken down by bacteria in your gut, feeding the bacteria and enabling them to multiply. It can be found in both food and supplements, just like viscous fiber. Fermentable fiber supplements are often purchased in gummy form and commonly contain inulin as the main ingredient. Gummy supplements are known to be less stable, meaning there is less certainty about their ingredient content remaining true to the label. If you are looking to get the most out of your fiber supplement, a powder or pill version may be more reliable. Other common ingredients you could see which indicate you are buying a fermentable fiber supplement are:

• Chicory root
• Polydextrose
• FOS (fructooligosaccharides) or resistant starch

If you are looking for general microbiome benefits, fermentable fiber could be an appropriate choice for you. Benefiber® and SunFiber® are both powder supplement options with modest prebiotic benefits. If you are looking to increase fermentable fiber through your diet, both onion and garlic are easy foods to start with. Remember, all fiber types offer a prebiotic benefit in your gut. The main difference is the rate at which they are fermented in your gut, as some forms of fiber in food are digested more quickly than others.

You also may notice many “high fiber” snacks contain ingredients like inulin, chicory root and FOS. These foods have been enhanced with a fiber ingredient to create a higher fiber product. A lot of these food products contain fermentable fiber sources (rather than viscous). Although these can improve your microbiome, they may not be serving all your health goals well. This is why reading the food or supplement label is of great importance, so you can understand not just how many grams of fiber are in a product, but the source of the fiber. Is it an added or natural fiber source? Does it offer viscous, fermentable or insoluble benefits? Just as it is not best to rely on a fiber supplement alone to meet your fiber needs, it is not optimal to rely on ultra-processed or fortified snack foods to meet your fiber goal. Remember to incorporate whole food sources of fiber into your diet; these not only provide a mix of fiber types, but many other vitamins, minerals and antioxidants as well!

Insoluble Fiber

Most whole foods naturally contain a mix of both soluble and insoluble fiber. Insoluble fiber is generally found in the skin or peel of plant foods and soluble fiber in the flesh or inside. A great way to visualize this is to think of the peel of an apple as insoluble versus the flesh as soluble. Insoluble fiber is most known for its use in aiding digestive regularity. It can decrease transit time of stool in the digestive tract, moving things along more quickly and improving bowel frequency. Even though insoluble fiber does provide bulk and speed to stool, it does not provide a strong viscous effect. This means it will not be as beneficial for lowering cholesterol, blood sugar or even keeping stool soft and easy to pass. Surprisingly, soluble fiber can be the best option for individuals with constipation to try first. This is because it provides a mixture of both bulk and softness to stool, unlike insoluble fiber. Toleration is personalized and everyone may benefit from different types of fiber for the best digestive response. The simplest way to add more insoluble fiber into one’s diet is to eat wheat bran from cereals such as All Bran Buds® or shredded wheat cereal. It is uncommon to obtain insoluble fiber in a supplement form.

Fiber Supplement Strategies

After you have chosen the best fiber supplement for you, it is helpful to understand practical strategies for how to best take these supplements. As you build your total daily fiber intake, it is most tolerable to start low and go slow. This minimizes risk of gas, bloating and discomfort. Fiber supplement dosing can start out as low as 3 g per day, working slowly up to 7-10 g daily. This can be taken in one dose or spread throughout the day into multiple doses. To increase fiber incrementally, try going up by around 5 g of fiber per week and monitor how you feel. You can make modifications to your approach, tapering the fiber dose up or down as needed to feel your best.

When adding more fiber to your diet, make sure you are adequately hydrating, as water is needed to help the fiber supplement have its intended effect and minimize bloating. If you find it difficult to drink your fiber supplement daily, consider Benefiber®, as it most readily dissolves in liquid and is less noticeable in beverages. However, if a viscous fiber is a priority for your health goals and Benefiber® is therefore not the best option, a psyllium husk option in capsule form could be a simple choice if you prefer not to drink your fiber supplement. The dose per fiber pill is much lower than in drink form, so you must be able to take at least six capsules, up to 18 capsules daily, to see benefits.

These are some of the most common types of fiber supplements available today, but the list is not exhaustive. The best option for you depends on your individual symptoms, health history and goals. Before taking a fiber supplement, discuss it with a qualified health care provider, such as a registered dietitian nutritionist or physician. They can help you choose the right type, dose and timing to maximize benefits.

If you need more information on recommended supplements, schedule an appointment with a Cooper Clinic Registered Dietitian Nutritionist. Visit cooperclinicnutrition.com or call 972.560.2655.

Article written by Jordan Harmon, RDN, LD, and Cooper Clinic Nutrition.